Assistente AI
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00:00:10Michele De Carli: Okay, so we started.
00:04:80Michele De Carli: Share the screen, share the screen. Okay, so, after, the…
00:13:280Michele De Carli: So we have, we had the one-week post, so I'll recouple it a bit. So we were starting looking at the fuller systems, okay? So, where we have,
00:27:340Michele De Carli: Okay? Where we had, the… we want to heat and cool the room with… just with the air. Okay, so the same air that is used for ventilation, air is also, okay.
00:43:400Michele De Carli: is also dealing with the power which is needed in the building in heating and cooling, okay? Which is, of course, calculated, as you have seen, in the QA. So, of course, we have not only the sensible,
00:59:760Michele De Carli: Decisible limit.
01:02:350Michele De Carli: balance, but we have also well authentic and honest, okay? And…
01:06:790Michele De Carli: I want to recommend that in the chart, in the ASHRA chart, okay, the psychometric chart, the, sensible power divided by the total power, okay, which is the sum of
01:22:820Michele De Carli: searchable latent, load, okay. Is the,
01:31:700Michele De Carli: Angle, inclination angle, the tilting angle of the line of the so-called room, or environmental line, okay, in which any point is suitable, okay, for supplier, okay.
01:49:480Michele De Carli: Leading to the indoor condition A, okay? So, given a certain condition A in the winter, for instance, 20 degrees C, and 50% of relative humidity, for instance, okay, then, in order to get this zone, sorry, this indoor condition.
02:08:490Michele De Carli: If we have… once we have calculated the sensible latent load, okay, the line which is inclined by the ratio between the sensible load and the wrong load, okay.
02:24:260Michele De Carli: So this line, every point of this line, is
02:29:60Michele De Carli: A point where, of course, with a suitable ventilation rate, okay, we are able to
02:37:310Michele De Carli: allowed to reach the indoor conditions A, okay? Of course, if we have
02:46:00Michele De Carli: We are in winter, okay, so we are supplying air at higher temperatures, so the inlet temperature of the air
02:54:00Michele De Carli: will be higher than 20 degrees C, okay, because we want to hit the building, so we need to face the losses of the buildings, okay? So we need warm air, okay, like when you are in the car, and you want to switch on the
03:09:800Michele De Carli: The heating, you needed to provide cold warm air, okay?
03:14:870Michele De Carli: Of course, the greater the temperature of the supply temperature, so the greater the distance of the point R to the room temperature A, okay.
03:28:330Michele De Carli: The slower will be the flow rate that we need to provide, because, of course, the… the sensible… the sensible gain, okay, so the power that we need, heating in this case, is the…
03:46:390Michele De Carli: Musterate…
03:48:550Michele De Carli: times the specific heat of the air, times the temperature difference between the air and the incoming temperature. Okay, so if we increase this
04:00:640Michele De Carli: this delta T, then we could decrease the ventilation flow rate. As I mentioned, okay, of course, in winter, we have no particular
04:13:280Michele De Carli: constraints, okay, so we increased, or we could supply air even at higher temperatures, okay, but of course.
04:20:730Michele De Carli: If we increase the temperature of the ink and in air, then air stratification, which means that we are not… we are not providing a sweet hole mixing of the air, okay, which is, of course, something that we want, as we will see.
04:36:780Michele De Carli: in a full air system. So, by keeping the temperature smaller, okay, so by keeping the temperature difference smaller.
04:47:30Michele De Carli: Of course, we can have a better, okay, distribution of the sort of a smaller, a smaller…
04:56:430Michele De Carli: grading of temperature, okay, stratification. And, of course.
05:02:920Michele De Carli: You have to think about that these systems have been widely extensively used in the 60s, 70s, 80s, when there was just,
05:16:280Michele De Carli: boilers, okay, so we were using the fossil fuels, so…
05:19:960Michele De Carli: basically, it was… it was not… I mean, that… it didn't make sense to really, consider too low temperatures, because with the boiler, it was quite standard to have
05:33:00Michele De Carli: 70, 80 degrees as water supply, okay, in the coil, okay, so water in the coil, in the thin coil, in order to heat up the air, okay? But, of course, now that we… and, of course, that could keep also the coil, okay, to heat.
05:51:550Michele De Carli: up there, also smaller, cheaper, okay? Of course, today, since we are more and more working with heat pumps.
06:00:410Michele De Carli: Okay, by decreasing the temperature of the supply area, we could decrease the condensation temperature, which means that we could increase the COP of the pump, so we could make the system more efficient, okay? And of course, that means that we need larger coils, because we need to
06:19:570Michele De Carli: to… to… because KS data t is the… the…
06:25:560Michele De Carli: mingle or bedroom, whatever you want, okay? In any case, the corn should be good.
06:31:130Michele De Carli: That is, that is where we went. Also, okay, and then we start, we have seen also, based on the calculation, on the example that you did, that also dye
06:42:510Michele De Carli: insulated the buildings, okay, the power needed in the room is decreased, so that we could also decrease the supply times, okay? That is why we made this exercise, okay, and with all the examples, in order that now you have, okay, you understand better this
07:02:630Michele De Carli: Because otherwise, you could be.
07:06:420Michele De Carli: You understand me. Okay. Oh, so that is, okay, through the heating. So, in heating, the inclination of the supply line of the room, okay, so the duration, leads to something like that, okay? In cooling, the air should be supplied as
07:29:510Michele De Carli: a quarter temperature, okay? And of course, a smaller, specific, some humidity ratio, okay? Humidity ratio has always to be smaller than the rule.
07:41:850Michele De Carli: Then the moon,
07:44:590Michele De Carli: humidity ratio, so critical content, because we have generation of water, okay? And, of course, we need to provide air at drier than the… than the…
07:58:310Michele De Carli: So, in this case, the inclination of the… of the line is this positive, okay? And because we are supplying the air at smaller temperature, because we want to cool the beating, of course, okay? And, of course, again, the smaller the temperature of the supply air.
08:18:570Michele De Carli: There's
08:20:600Michele De Carli: So, the greater the temperature difference between the supply air and the room air, okay, the smaller will be the mass flow rate that we need to supply to the room, okay? Now, in this case, we have a limit which is fixed at 16 degrees, okay? So, in this case.
08:38:980Michele De Carli: I don't know, we try not to go.
08:41:100Michele De Carli: Below this limit, because this is due… this could lead to surface condensation in the air parlina devices, okay?
08:50:140Michele De Carli: Did we see Artemia devices? No. Yes.
08:54:460Michele De Carli: Yeah, okay, don't admit that.
08:56:540Michele De Carli: Okay. Anyway, that is, okay, how it works. So now, the question is how we could reach this point here, okay, for the supply in winter, and this point here for summer, okay?
09:13:590Michele De Carli: Okay, so, no, that is, of course,
09:21:730Michele De Carli: The first part is to decide to fix which is the inlet temperature, okay, as
09:27:800Michele De Carli: And of course, you can sell… you can choose, okay, considering the different combination of the different choices.
09:38:770Michele De Carli: Remember that, There is always a minimum requirement of
09:44:620Michele De Carli: flow rate, okay, which is related to the indoor air quality, okay? So, let's say 10 liters per second per person, okay? It is not completely related like that, okay, we could… but let's keep this figure, okay, which is, okay, a well-established
10:00:800Michele De Carli: figure for the ventilation for the fresh air, okay? So, we cannot go below, okay, this Which is…
10:11:340Michele De Carli: I want to remind you, 40 cubic meters per hour, roughly speaking, okay? So, 40 cubic meters per hour per person, okay? This is the amount of air that we need, okay? We are here, we are 50, 50 places, so that means that we need here 50 times 40, okay? Could be 40… 51, because it's also myself, but it doesn't matter, so that is 3,000 cubic meters per hour.
10:35:680Michele De Carli: Okay? So, in order to keep this rule, if we would Keep this room with…
10:43:220Michele De Carli: Good air quality, not poor air quality as we have, okay?
10:47:450Michele De Carli: But, you know, equalizes, okay, so that is why we have not had a continuation system here, okay? So, the, as you can see, 2,000 kilometers per hour, okay, we are…
11:04:30Michele De Carli: A little bit above the…
11:07:00Michele De Carli: mechanical ventilation system that we have seen, okay? So we are, okay, for… in this case, we should need, okay, some air, which is…
11:20:80Michele De Carli: Okay, limiting… it's in the limit of the mechanical ventilation system that we have seen for the residential vehicle, you know? I told you it's 1,500, okay, cubic meter per hour maximum, okay?
11:33:80Michele De Carli: Okay, it doesn't matter. Anyway… So, as we have seen in the, in the, in the examples.
11:41:140Michele De Carli: If we… if we have enough air, so if the amount of fluorid, okay, so if this, for instance, 2,000 cubic meters per hour is sufficient to fulfill the law of heating and cooling, then we just use fresh air, okay? Because fresh air is the minimum requirements for indirect quality, okay, and that is why
12:02:930Michele De Carli: what we could use here. But if we want, but if, for instance, there is a discrepancy between the fresh air and the, and the fluid.
12:15:960Michele De Carli: by share flow rate, and the flow rate that is needed for facing the heating and cooling peak load, okay, then we need to recirculate some part of the air, okay? That is also what we have seen in the last, in the last,
12:31:940Michele De Carli: In the last, but, very cool.
12:36:770Michele De Carli: Of course, we have to think about, okay, and that is what we are going to see, that we will talk about the design conditions, okay, but then we have to think about how to make the system, okay,
12:55:240Michele De Carli: how to allow the system to, let's say, change the conditions over the time, okay? So we want to consider the design conditions, okay, but we have to think also about, let's say.
13:08:990Michele De Carli: Some, conditions, okay, we need to consider when we size the system and this system, we need to consider also how the system could work
13:18:640Michele De Carli: In, far from designing conditions, as we will see.
13:24:740Michele De Carli: So, now, let's have a look at the most simple, the simplest solution that we have, okay? So, I told you, we need to keep the room temperature, and we need to supply the
13:39:400Michele De Carli: here, okay, in the different rooms, okay? We need to, to… Allow?
13:50:590Michele De Carli: So this is the AR Henry unit, and this AR Henry unit, okay, is responsible to reach the inner temperature in these conditions, for instance, 16 degrees C, and, what is the difference?
14:05:820Michele De Carli: 65% of relative humidity, for instance, in the summer, and we want to supply… to…
14:12:390Michele De Carli: to get fresh air at 30 degrees C and 20% of relative humidity, okay? So, of course.
14:21:430Michele De Carli: In this case, we could have minus 5 degrees C as outdoor temperature, and in this case, we could have 34, 35 degrees C, and 40% of relative humidity. Okay, so we need to handle there in order to go from this
14:37:720Michele De Carli: sorry, from this point here, which is the supply temperature here, and in winter, we need to go from this point here at minus 5 degrees C, okay, designation, to this point at 30 degrees C, and this, relative humidity.
14:53:230Michele De Carli: So, this has everything which is, what is done in the AI handling unit. So, in the handling unit, what you do, you are
15:03:390Michele De Carli: Taking the outer air, intaking outer air, okay, fresh air, in case you have some recirculation, as you have seen, then we need some features, we will see what, okay, next, next, the next letter will be on air and reunit, okay, after this letter.
15:21:560Michele De Carli: And, and then we are told to supply data at this
15:26:700Michele De Carli: two conditions, the design conditions, in winter, etc, okay? And, of course, we have, we could have the same flow rates, because the rules could be the same, okay? It means that you have the same rules, okay? One above the other, one
15:43:640Michele De Carli: goes, yeah, huh?
15:45:750Michele De Carli: But we could have also rooms with different size, okay, and in this case, we should consider different flow rates because of the size of the rooms. But what is important is that in this case, you have the same
16:00:510Michele De Carli: Supply temperature. Okay, so you have the same supply temperature, which means that the
16:06:660Michele De Carli: that the inclination of the line should be the same in all the rules. So all the rules, they have to be similar loads, okay?
16:17:990Michele De Carli: So, this is the so-called single duct, because in this case, you are heading here, you have one duct, which is supplied here in each room, and then you have one dot for the return, okay, for the return.
16:32:260Michele De Carli: And then exos indicates the recirculation. Okay, so the recirculation is not mandatory, okay? It's, okay, something that could be, or they could be present only.
16:43:250Michele De Carli: So, you need that, so you need that,
16:52:230Michele De Carli: you… you need the same line for each room, so on, okay. And this is, for instance, okay, what you could do in case you have one building with… which is… which has the same,
17:07:810Michele De Carli: orientation, okay, so imagine that we have these rooms, okay, facing east, okay? And in this case, all these rooms, they have similar rules, okay, so that you can use just one, one urn unit for this zone, okay? So in this case, for instance.
17:28:740Michele De Carli: If you could consider to have
17:31:100Michele De Carli: Let's make a very simple sketch, okay?
17:34:400Michele De Carli: Imagine that this is an office, an office,
17:39:280Michele De Carli: building, okay, this is the corridor, this is west, and this is east. And imagine that this is… this could be the glazed, okay, the surface, doesn't matter which is the ratio of the glaze, okay? But in this case, okay, you could then have an air handle unit.
17:55:800Michele De Carli: just for the Eastern, orientation.
18:00:640Michele De Carli: 1, 2, 3 floors, whichever… how many floors you want, okay? And
18:07:390Michele De Carli: a percent limit, okay, and then you have an RNA unit, okay, with a single duct on the west side, okay? In this case, you can provide
18:17:230Michele De Carli: Ventilation and load for these two different areas, okay, and it's okay, because in this case, you could have similar loads
18:28:850Michele De Carli: on east side and west side, okay? That is a possibility, okay? So, now, what are the, which are the…
18:39:620Michele De Carli: The… the transformations are the… the… the… the… the…
18:48:440Michele De Carli: Yes, the… how can you handle the air? How can you go from outer air, in case with recyculation, okay, to the supply, warranty temperature and condition, let's say.
19:01:350Michele De Carli: So, first of all, you have seen them, okay? There are some, okay, blades on the, on the,
19:14:380Michele De Carli: external intake and air intake and recirculation. And they are used, okay, in order to balance the flow rates, okay? If there are tweaks, you do it once, okay? So, at the beginning, at the starting operation, okay?
19:34:110Michele De Carli: In the beginning, or when you finish the works, okay?
19:37:500Michele De Carli: they can have some electric engine, okay, as you have seen in Bellimo, okay, you could have some electric, okay, engines, okay, so you can have several motors that they can adjust the, okay, inclination of these blades, so that you can open and close partially these blades, these dampers, okay, in order
20:01:470Michele De Carli: And in this case, it could be used in order to have a variable in case both
20:07:820Michele De Carli: out of air, and in case there is circulation fluid, okay? So, it doesn't matter, okay? In any case, you usually have this because
20:18:740Michele De Carli: You need to, okay, once you install the air handling unit and the ventilation system, you need to tune and balance, okay, when it is done, because
20:30:700Michele De Carli: You could do the perfect…
20:32:360Michele De Carli: Work, okay, but then the reality can be slightly different from what you have, okay, designed.
20:39:450Michele De Carli: So, these are the equalizing dampers, okay? Then you, you can have, okay, so this is the most complete solution, okay? Then, but there might be some changes, okay? So this is the most general scheme of an LMD unit, okay?
20:57:00Michele De Carli: You could have a protein coil, okay?
21:02:70Michele De Carli: then you could have an atomized… a humidifier. It could be atomized or isothermic with vapor humidifier. We will see
21:15:30Michele De Carli: with the solutions, okay. Of course, you need some droplet separator, okay, in order to avoid that drops will flow to the dots, okay? Why?
21:31:630Michele De Carli: What did I tell you about water? What is the problem related to water from the health point of view?
21:39:160Michele De Carli: Mold, and especially. Okay, so you need to really take care about the water, okay, content through the dots, because then it might have laser model problems, okay?
21:53:200Michele De Carli: Also, in this case, okay, the… the… in case you have some water, there's no water, this has to be drained, okay? So once you could circulate it, okay, in the 50s, 60s, but then after the residential program, it was
22:08:560Michele De Carli: But really, not the obstacle anymore.
22:12:740Michele De Carli: So, then you have the, cooling oil, okay?
22:19:60Michele De Carli: And then you have the rate coin, okay, and we will see the different, the different, the different,
22:29:940Michele De Carli: That's a mission.
22:31:420Michele De Carli: This is the, this is the general solution, okay? This is the general old scheme, let's say, okay? Why? Because in this case, we are just considering
22:43:320Michele De Carli: outdoor air, and we mix that with the… with the indoor air, okay? So, when you mix outdoor air with indoor air, you reach an internal date point, and this point, the mixing point, will be
22:57:780Michele De Carli: Much closer to the outer air, if you had more outer
23:02:160Michele De Carli: fluorate than recirculated fluorate, and vice versa, okay? Why is all that?
23:13:580Michele De Carli: Efficiency of a deletion system. How can you lead against efficiency of a deletion system?
23:20:780Michele De Carli: heat recovery, yes, you have no heat recovery unit, okay? So in this case, it took just the outer air, you mixed that with the inner air, then it was used, very much used, the credit card, okay, in order to, let's say.
23:37:880Michele De Carli: reach the temperature, which was then possible by the atomized humidifier, okay, to reach the wanted
23:49:480Michele De Carli: humidity ratio, okay, for that inlet condition, okay? So the preheat coil was used in order to, let's say, reach the wanted vapor content, okay, in the supplier, and then the reheat coil… preheat coil… the reheat coil was used in order to reach the input.
24:09:350Michele De Carli: With the supply conditions, okay?
24:13:190Michele De Carli: You're designing, you are writing it.
24:16:40Michele De Carli: If I… if I say something wrong, you can… you can correct me, yeah? Okay. If you have some doubts, your colleague is designing a review unit, okay? So she's the best, okay, most authorized person, okay? So I can… I can nominate her.
24:34:250Michele De Carli: Alright, so… Oh, I don't want to…
24:44:70Michele De Carli: Alright, so this is how it works, okay? Of course, this is the…
24:52:130Michele De Carli: new skin, okay, for the same heat recovery unit. In this case, with the heat recovery of about 70%, okay? In this case, you will heat up the air, okay? Of course, all heating
25:05:790Michele De Carli: All heating, all heating, processes are, okay, at fixed humidity ratio, okay, so all the heating
25:16:480Michele De Carli: all the heating transformation, they are, without any, okay, at constant at constant humidity reaction, okay? So, in this case, you use the heat recovery unit. You could, in case, mix the…
25:31:640Michele De Carli: And in this case, usually you could directly, okay, go into the, the automized modifier, and, and then you, you, with the receipt call, you can, you can, okay, supply the
25:46:300Michele De Carli: Okay, you can see that in this case, you don't need… you have… you're just saving energy, because in this case, you don't need the preheating coil, okay, which is… was usually, you… was… was usually using, okay.
26:02:00Michele De Carli: for heat fuels, okay? So in this case, with the heat recovery unit, you can save energy, okay? Of course, you could also use
26:11:770Michele De Carli: Okay, and that is much… could be much more, also, energy saving. Steaming humidifier, okay? You know when you humidify the air with the steam, it's almost okay as a thermal condition, okay? So in this case, you could just,
26:31:90Michele De Carli: We could just, increase the results in my day long.
26:36:790Michele De Carli: by the one with the delta X, okay?
26:40:920Michele De Carli: producing the amount of… Okay. Also, this is also easier, okay, to control, because it's just the amount of power that you… but, okay, it doesn't matter. I want to remind that, okay, you are…
27:00:970Michele De Carli: From the thermal comfort point of view, okay, you could, if you, if you…
27:07:200Michele De Carli: Imagine that this is the line.
27:10:580Michele De Carli: Okay, well, it is a very inclined line, but it doesn't matter, okay? In case you're not humidity, fine, okay, you are, okay, supplying the air here, okay, but in this case, also, the relative humidity will change, okay, so… okay.
27:28:700Michele De Carli: forget. What I want to say is that, in principle, it's up to you if you want to use the humidifier or not, since the humidifier could be… should be maintained, because then it could be provide… it could provide problems for the Zonella.
27:45:210Michele De Carli: Sometimes, okay, the… even though you designed the… the… the humidifier, sometimes the humidifier will then won't work because of high costs of maintenance, okay?
28:06:840Michele De Carli: I wanted to add another issue.
28:12:760Michele De Carli: No, no.
28:19:120Michele De Carli: Okay, sweet.
28:20:340Michele De Carli: Sorry, I forgot to… There was an additional comment I wanted to add. Okay, doesn't matter.
28:35:860Michele De Carli: I don't know.
28:37:80Michele De Carli: Alright, so, that means for heating, okay?
28:47:660Michele De Carli: Okay.
28:50:580Michele De Carli: Now, this is the case for cooling, okay? What, what, what happens in cooling? In cooling, of course, this is the supply, condition. Okay, here we have 60 degrees C at about 75% of relative humidity, more or less, okay? And this is the line.
29:09:700Michele De Carli: Okay,
29:15:240Michele De Carli: Here, okay, the general condition is to mix up the outer air with the air, okay, then you have a mixing condition here, okay?
29:24:30Michele De Carli: or whatever it is, and then you will cool down the air. Yes, sorry, I wanted to show you that. Okay, so this is…
29:34:840Michele De Carli: So this is the scheme, okay?
29:40:220Michele De Carli: So… Thinking about what we have seen, we have the pre…
29:49:640Michele De Carli: the Prehitco, which could be, in principle, also not used, okay, in case you have the heat recovery unit, okay?
29:57:190Michele De Carli: You could have the, the, rare heat coil, okay, which is the 6 here, so this is usually the, the, the, the, the cooling or heating coil, they are also, okay, they have a plus or minus, okay, plus means heating, minus means cooling, okay? So this is with plus, okay, so this could be, okay, the general solution, okay, in case you, of course, here you
30:22:190Michele De Carli: will have a need recovery unit, which will be on board of the air handling unit. Okay, so…
30:27:940Michele De Carli: the useful, the useful, one of the pros of the RME unit is that you can, okay, locate everything, okay, in a specific
30:39:450Michele De Carli: volume, okay? And everything is there, okay? That is the main core of the air healing.
30:46:700Michele De Carli: Brooklyn.
30:51:660Michele De Carli: Yes, just to mention, okay, as you have seen also in the, in the most iconor, okay, here.
30:59:880Michele De Carli: Usually, In the past
31:02:990Michele De Carli: Also today, you can use water, but in principle, you have seen that there are today, okay, available,
31:10:660Michele De Carli: energy unit with either condensation, okay, so with the refrigerant gas, okay, so there are solutions with… so direct expansion, units on both of the RNA.
31:25:830Michele De Carli: Okay,
31:30:270Michele De Carli: Okay, so now, in this case, you have the cooling, so you're cooling, so you need to cool down the air, and as I want to mention that for air, usually you need to go 7, 12, okay? You could even go
31:47:960Michele De Carli: 8, 9, 13, okay.
31:52:00Michele De Carli: When could you have higher temperatures?
31:57:410Michele De Carli: Any idea?
32:01:400Michele De Carli: Usually, the usual temperature is 712.
32:07:00Michele De Carli: When could you have higher temperatures? 8, 13, or 9, 13?
32:19:70Michele De Carli: No, no, no, this is for cooling down the… That's the mixing point, I think. Yes, it depends on the mixing point, but it… so it depends on the generation type of…
32:33:870Michele De Carli: Yeah. If, for instance, you're using… if you are connected to a district cooling network.
32:42:720Michele De Carli: Usually the district cooling factor, okay. The temperature of butcher, it's the second system. Yeah. Yeah. So, in this case, usually you have the heat exchanger, okay, on the basement of the building.
32:55:380Michele De Carli: And the heat exchanger is exchanging with the district cooling network, okay, so the distant cooling network could work at 7, 12, or 6, 11, okay? And in this case, your temperature in the coil, okay, will be slightly higher, because you have a heat exchange, okay, so…
33:12:770Michele De Carli: And in this case, okay, but you couldn't go above 9 degrees C as supply temperature, because in that case, you are… you would not be able to dehumidify the air. Okay, so the…
33:25:60Michele De Carli: the limiting temperature is, let's say, 7, 8, 9 degrees C, okay, as maximum temperatures in order to cool and dry the air, because… and that is, okay, a limiting condition, okay, for…
33:39:970Michele De Carli: for the cooling system. So, here, okay, you have two options, as we have seen. Either you… you are working, you could, in principle, get out at a certain temperature.
33:54:280Michele De Carli: The general condition is you pull down here, and then you have the raised coil, okay, which…
34:03:130Michele De Carli: can be used, then, to, have the air entering at 16 degrees, okay? So, you have the red column here.
34:13:989Michele De Carli: And you have the ray heat coil here, okay? So, in any case, you have the reheat call, okay? So, in this case, then the, the system could be just with a…
34:29:540Michele De Carli: Cooling coil, okay, or… and the red coil, or you could work with
34:37:250Michele De Carli: a coil which is heating and cooling, and here you have the rate coil, okay? So, it depends on…
34:44:80Michele De Carli: Right?
34:45:520Michele De Carli: Correct?
34:46:739Michele De Carli: Okay. Okay. I don't, I don't want to create problems, okay? So, anyway, so this is, what happens in case of a heat recovery unit, okay? So in case of a heat recovery unit.
35:02:410Michele De Carli: As we have seen, you are… you have 70% of, heat recovery, okay? Usually, this heat recovery is not really leading to, to… it's just a sensible cooling, okay?
35:17:80Michele De Carli: So in this case, you're going from, let's say, 35 degrees, in this case, to, let's say, 29, okay? Dynamics, but again, you need the rate coil, okay? So the rate coil is, in general, necessary.
35:33:250Michele De Carli: Okay, now…
35:41:570Michele De Carli: Yes, I want to remind that the flow rates, okay, in heating and cooling.
35:48:660Michele De Carli: They could be different, okay? So, if you need… if the flow rate for indoor air quality is sufficient to meet the
36:00:00Michele De Carli: heating and cooling low, okay, then you use the same flow rate, but in case you have to recycolate here, okay, in principle, the two flow rates could be different, okay? So you need to consider different flow rates, just in case.
36:14:170Michele De Carli: Today, again, is not a problem, okay, because with the engines that we have today, the brushless engines, okay.
36:21:140Michele De Carli: Then, by changing the… the voltage of the… of the…
36:26:380Michele De Carli: engine, you could, okay, change the speed of the fan, and in this case, you can, okay, adjust the throw rate, okay? So, but in the past, it was a problem.
36:36:620Michele De Carli: No!
36:38:780Michele De Carli: This is… What… how the, system works.
36:46:320Michele De Carli: But we have, we have a very,
36:56:500Michele De Carli: I told you, we need not only to size the system for… just for the design conditions, but we need to keep in mind how the system could work.
37:05:690Michele De Carli: Outside the design conditions. Which could be the worst condition
37:12:800Michele De Carli: when we want to search the red call, okay? So, for the red call, Including?
37:20:620Michele De Carli: what could be one condition which is far away the design condition? Okay, so the condition that we might have is a cloudy day.
37:34:460Michele De Carli: But humid day, okay? Here, we have, you know, many days like that, okay? I don't know, did you experience, right? Okay, so, so the climate here is quite humid, okay, as in other places, not only here, okay? But there might be few or several days.
37:52:650Michele De Carli: In summertime, where you have not so much
37:56:90Michele De Carli: solar radiation as the design condition. Design condition, I want to remind you that it's perfectly clear sky condition, okay?
38:04:320Michele De Carli: Back to you with, anyway.
38:06:680Michele De Carli: Okay, so you meet, And… no.
38:11:550Michele De Carli: Limited solar radiation. So, the most critical condition is without any solar radiation, but humid. So you need to cool and humidify the air, okay?
38:23:10Michele De Carli: In this race.
38:27:720Michele De Carli: What do you add?
38:31:200Michele De Carli: Imagine that you are in the… Let's say, most extreme condition.
38:38:720Michele De Carli: That the sensible road is known, Okay?
38:42:270Michele De Carli: But still, you have the latent load in the room, okay? So, the numerator is 0, and the denominator is, of course, the latent load.
38:53:360Michele De Carli: Which is the line represented by zero?
38:59:780Michele De Carli: Vertica? Right. It's vertical.
39:04:980Michele De Carli: What does it mean?
39:07:180Michele De Carli: It's the only reason to eat.
39:10:50Michele De Carli: that our… Supply temperature?
39:14:420Michele De Carli: Should be in the vertical line.
39:17:560Michele De Carli: Right? Because in that moment, The line will be not anymore inclined, But it will be vertical.
39:26:260Michele De Carli: What does it mean? It means that we need to supply air at neutral temperature, okay? Of course, we will have
39:35:400Michele De Carli: we will add.
39:37:690Michele De Carli: some internal gains, okay? But in this case, imagine that you are no solar gain. How many of you did already the carrier method?
39:47:690Michele De Carli: Which is the meg… the… the major…
39:51:440Michele De Carli: load that you have in the calculations.
39:53:880Michele De Carli: What is maybe you won't go into CP World.
39:59:620Michele De Carli: No, no, no. Which is the… I mean, considering the different calculations that you did, which is the most dynamic input for the power?
40:09:10Michele De Carli: Put it both.
40:11:750Michele De Carli: Coming from the wars, Interpretation, real solar radiation. Solar radiation. Okay, so, the major, the major contribution, okay.
40:24:190Michele De Carli: But in usual buildings, okay, then if we have a data center, then the internal loads will be cut the most relevant point. Let me say that usually, the cell elevation is the most critical condition.
40:35:270Michele De Carli: So, in this condition, Okay? You should provide dry air.
40:41:90Michele De Carli: But you don't want to undercool the building, because otherwise people could freeze in, okay? So this… so in that case, the supply temperature should have the same
40:53:240Michele De Carli: in their temperature. So, 26 degrees.
40:56:900Michele De Carli: Aaron, but… Then, the rate coin.
41:01:350Michele De Carli: In design conditions, for instance, stops at 1670 degrees C,
41:07:360Michele De Carli: But in these special days, you need to heat up the air up to 26 degrees.
41:14:840Michele De Carli: Which is the point which leads to higher power.
41:19:310Michele De Carli: From the water side in the coil.
41:24:130Michele De Carli: which is the greatest power that you need to provide to the air, okay? So… Yeah, the coil?
41:34:200Michele De Carli: with water?
41:38:950Michele De Carli: 7 degrees C, 12 degrees C.
41:43:330Michele De Carli: No, Castos, we're not there, sorry. I… we are in reducing, okay, so let's consider 30 degrees, for instance, and 25 degrees.
41:52:430Michele De Carli: Okay?
41:55:950Michele De Carli: We are in the red car.
41:58:390Michele De Carli: Should we provide more power to the air?
42:02:800Michele De Carli: with a central rate over here, when we need to heat up here by 3-4 degrees, or by 10 degrees C.
42:12:950Michele De Carli: And you see.
42:14:920Michele De Carli: So, the rate column should be sized, for tentacles.
42:21:760Michele De Carli: So… Among the two, power, The red coil should be selected, okay, to cover.
42:31:880Michele De Carli: To let the air enter at the same room temperature.
42:37:560Michele De Carli: Because in case of no sunny days, okay, you could then humidify the air, without undercooled the building.
42:48:260Michele De Carli: Okay?
42:50:30Michele De Carli: Is it clear?
42:52:720Michele De Carli: And that is the main difference between the…
42:57:430Michele De Carli: fuller air, but also the primary air. So, also in case we imagine that in this room.
43:03:680Michele De Carli: We could provide air, the humidified air, with a cooling system.
43:09:80Michele De Carli: Right in this room, okay?
43:12:550Michele De Carli: What happens if we have cloudy conditions outside?
43:18:260Michele De Carli: And we adjust the cooling machine here, to the front continuables.
43:23:570Michele De Carli: How do you control the… the… the… Thank you guys.
43:32:440Michele De Carli: So, if you have no Solar abrasion coming, okay?
43:39:30Michele De Carli: You easily see… reach 20 CPBC.
43:42:500Michele De Carli: I cannot amplify because the system is switched off.
43:46:250Michele De Carli: If you want to, the earlier, you… Feel good to practice humid.
43:52:420Michele De Carli: Or you feel cold, but… We're dying.
43:56:580Michele De Carli: So that is the main point, and the main difference between
44:00:560Michele De Carli: Handling the air, and having a system.
44:04:600Michele De Carli: Or… okay, honey, Nick.
44:07:180Michele De Carli: Full water system.
44:09:340Michele De Carli: Like this. Okay. And… bye, heavy.
44:13:810Michele De Carli: Infiltration or mechanical ventilation without having an air.
44:18:440Michele De Carli: In.
44:20:370Michele De Carli: In cloudy days, but humid conditions.
44:24:800Michele De Carli: If you have just a full water system.
44:27:870Michele De Carli: You will under cool the living if you want to feel comfortable, because if you… either you feel good from the temperature point of view, but it will be too humid inside, or you could feel comfortable for the humidity.
44:41:930Michele De Carli: But you will, under cooling.
44:44:260Michele De Carli: do we have another call, okay? What is right?
44:47:470Michele De Carli: I start with the Fuller system.
44:50:40Michele De Carli: and not with the water system, because now you know that, and you understand that. If I would have started with the
44:59:250Michele De Carli: water system.
45:01:00Michele De Carli: You couldn't understand this poem.
45:02:930Michele De Carli: Okay? So, from the thermal comfort point of view, the best solution is to provide They humidify the air.
45:11:340Michele De Carli: End?
45:12:840Michele De Carli: Then, water.
45:15:690Michele De Carli: System for the sensible, okay?
45:19:280Michele De Carli: or full air. Okay, with the full air, you can do that, okay? But remember, what we said here for the full air is also okay for the mixed, okay?
45:31:360Michele De Carli: primary air, so ventilation air handled there, with a water-based system, okay?
45:39:570Michele De Carli: Clear?
45:41:310Michele De Carli: Okay.
45:44:170Michele De Carli: Of course, the cooling call will be… will be selected, okay, we'll have the power.
45:50:590Michele De Carli: which is HE, in this case, minus H, that is this B, okay?
45:56:510Michele De Carli: And, of course, M0.
45:59:330Michele De Carli: Or GA. Okay, we said GA. Okay, so the mass flow rate times the enthalpy difference between the outer and the…
46:08:610Michele De Carli: I'll get the coil getting out from the battery, from the coil, okay? This is the cooling power of the coil. The electric power of the coil, in design conditions should provide this power, but, I mean, it should be sized for reaching the neutral conditions for neutral.
46:28:490Michele De Carli: Alright?
46:29:750Michele De Carli: Focus.
46:32:100Michele De Carli: Woof!
46:36:440Michele De Carli: That's all for this system, okay? But, of course, we said we have a system which is, okay, good.
46:46:110Michele De Carli: We can locate, for instance, okay, we are doing… or we could also use single dots.
46:53:610Michele De Carli: Also, in case of… Also in case of… Let's a mixed.
47:00:230Michele De Carli: Okay? To air and water system, okay? With the air. The water system, you could use the single dot, okay? This is the general scheme. Also, hour for this condition, okay, when you want to serve… when you have an area which is, you know, quite,
47:17:320Michele De Carli: with the same loader, okay? But also, in case you have some… any kind of water-based solution for cooling the system, okay? So, tank oil, radiant system, etc, okay? This is the scheme, the general scheme that you have for the air.
47:34:50Michele De Carli: Okay? Now, how can I do this system more flexible? How can I make this system more flexible? Well, there are several ways, okay? One possibility.
47:47:250Michele De Carli: East…
47:48:670Michele De Carli: to locate the red coil not on the unit, but to locate the road coil in the different areas, okay? It could be rooms, or it could be groups of rooms, okay, in case they are. Okay, so in this case, for instance, instead of this solution, I could put
48:08:560Michele De Carli: just one air hanging unit here, and then I could have maybe a rate coordinator.
48:14:470Michele De Carli: on the west side, and one red coil on the other side, so that I can tune the supply temperature according to the load that is required in a certain area, okay? So in this case.
48:28:350Michele De Carli: I still have the same air handling unit, okay, but I will locate the red coil, okay, in the business, of course.
48:37:260Michele De Carli: It will be more costly, because in this case, you have
48:40:730Michele De Carli: The coils, okay, which are in the buildings, you need to provide water, okay, to these coils, and you… we need some, okay, control strategy for…
48:50:600Michele De Carli: But this is a way to make the system more flexible, okay? So that you can have, for instance, 90 degrees C entering air here, or
49:04:190Michele De Carli: 21, okay, depending on the load that is required and everything, okay? So everything could be adjusted just by improving the supply temperature. Of course.
49:15:300Michele De Carli: You have the same?
49:17:700Michele De Carli: humidity ratio getting out from the air. Okay, so in this case.
49:22:820Michele De Carli: You have two options, okay? This is the usual.
49:28:420Michele De Carli: outdoor use. We usually control the room temperature.
49:36:00Michele De Carli: Okay, so since you have a text, the supplier.
49:40:250Michele De Carli: Okay? Humidity. In this case.
49:45:710Michele De Carli: You will adjust the… you could, work, and you could just adjust the, the room, sorry, the…
49:55:830Michele De Carli: you can control the room temperature, okay? But you have… you will have some fluctuations, okay, of relative humidity. But, as we are seeing, relative humidity is not a big problem, okay? I mean, we could go from 40 to 60, okay, it's not a big problem, from the kind of point.
50:14:810Michele De Carli: This is the general rule, and we could decide to Instead, Keep the relative humidity fixed.
50:25:500Michele De Carli: It's quite rare. Where could we have this kind of solution?
50:30:460Michele De Carli: Put it, especially museums, okay, where we need… where we have some hand drops, and so…
50:35:310Michele De Carli: Some paintings, okay, for instance. In this case, we could be more interested in keeping the relative humidity constant.
50:43:740Michele De Carli: Okay, by, okay, some adjust in the touch. Okay, so we could fluctuate between 24 and 27, okay? 26, 27, 25, okay? But we want to keep the relativity fixed. Okay, so this solution…
51:00:700Michele De Carli: Is good, because in this case, we can set… we can adjust the supply temperature, But you could observe
51:11:550Michele De Carli: With a control on the temperature, or on the electric vehicle.
51:15:180Michele De Carli: Okay, this is the…
51:16:900Michele De Carli: Small limitation, but yeah, okay? But it's not, I mean, it's not a big problem, okay?
51:23:570Michele De Carli: So, usually, this is the… the… so the parameter to be set is the air temperature, but sometimes it might be a scenario.
51:35:680Michele De Carli: Okay.
51:37:310Michele De Carli: Now, it is important to consider in case of recirculation. In case of recirculation, you need to take care about the traits that you have to keep for
51:52:890Michele De Carli: The air quality in the rooms, and the overall flow rate that is needed for them.
51:59:290Michele De Carli: Okay, so this is an example.
52:01:660Michele De Carli: So, you can see here my 3 rooms with 3 different loads.
52:06:630Michele De Carli: 1.85 kilowatts, 5.5 kilowatts, and 7.6 kilowatts, okay? So, according to the temperature that you need to supply 16 degrees C, okay, you have
52:21:60Michele De Carli: Based on the load, okay, so in order to face this load, this is the flow rate that you need provided. Okay, so in this room.
52:32:490Michele De Carli: 2,250 kilometers per hour, in this case, 1,500, and in this guy, in the other case, 550 cubic meters per hour. So these are the flow rates which are needed, okay, for the
52:49:90Michele De Carli: for the road that is… that is due in the building, in the rooms, okay? So, in order to face 10 degrees C of temporal difference, okay, you need this right in this room, this row right in this room.
53:03:640Michele De Carli: But… According to…
53:06:510Michele De Carli: According to the room size or the people that you can… that you can estimate, okay, the pressure
53:18:590Michele De Carli: Should be 300 cubic meters in the first room.
53:23:70Michele De Carli: 500 cubic meters.
53:25:450Michele De Carli: power, sorry, in the second room, and 800mm power in the second.
53:30:550Michele De Carli: Why I'm doing that? Because…
53:33:970Michele De Carli: We said everything is centralized. Okay, so the… the… the… the mixing will be here in the end, okay, so I'm… and I'm… I'm rotating the mixing there, and of course.
53:50:100Michele De Carli: No?
53:52:390Michele De Carli: If I make the ratio between the fresh air which is needed in each room, divided by the overall air, so if I make
54:03:00Michele De Carli: 300 cubic meters per hour divided by 500 cubic meters per hour. This is the ratio of fresh air with respect to the overall air flow rate that I need to supply to the room, okay?
54:15:970Michele De Carli: And in this case, I have more than 50% of fresh air compared to the overall flow rate that I need to provide to the room, okay?
54:28:440Michele De Carli: In this case, It's 1 3rd, okay, so 0.33. 500 divided by 1,500 is 0.33.
54:39:690Michele De Carli: And in the third case, I have… 800 divided by 2,200 is…
54:46:860Michele De Carli: Slightly less than 0.4, okay. So, 0.36.
54:52:340Michele De Carli: Which is the most… Severe condition.
54:58:100Michele De Carli: How should I select the ratio that I have to…
55:03:850Michele De Carli: that I have to provide in there, and really unit between the recyculation flow rate and overall flow rate.
55:11:120Michele De Carli: Sorry, fresh air for it, and… Overall.
55:17:20Michele De Carli: If I select this, Okay?
55:21:670Michele De Carli: Then, the fresh air would be… 550, if I want.
55:29:310Michele De Carli: Let's say.
55:33:190Michele De Carli: That's right there to get the truth.
55:36:390Michele De Carli: 200.
55:38:420Michele De Carli: Okay, so if I use this.
55:42:340Michele De Carli: ratio. In the first row, I would have, okay, 0.36 times 550, right?
55:56:490Michele De Carli: Times 550 will lead to 200 km per hour.
56:03:840Michele De Carli: But I need 300 cubic meters per hour.
56:06:870Michele De Carli: Okay, so I would not have sufficient indoor air quality condition, because in this case, I would use smaller amount of fresh air.
56:17:450Michele De Carli: Okay?
56:18:760Michele De Carli: So… The most critical condition, Is the maximum?
56:25:890Michele De Carli: of this value. Okay, so the maximum value of the ratio between the fresh air and the overall fresh air that I need to provide here.
56:36:380Michele De Carli: This is the value that I need to use in the central air handling unit.
56:42:550Michele De Carli: Because this is the most critical rule, Okay, which is brown.
56:49:410Michele De Carli: The overall recyculation rate in the building.
56:54:690Michele De Carli: Of course!
56:56:560Michele De Carli: In order to keep About 50% of fresh air.
57:01:410Michele De Carli: I needed to increase
57:04:510Michele De Carli: the fresh air in the other rooms, okay? So, I will then need to increase from 500 to 820, which is…
57:15:510Michele De Carli: 0.54 times 1,500, and 0.54 times 202…
57:24:830Michele De Carli: 2,250 is 1,230 kilograms per hour. Okay, so, I mean, then…
57:33:960Michele De Carli: increase the fascia, which means that I need to spend more energy, but
57:40:280Michele De Carli: It is something that I cannot avoid, because I want to keep the, okay, indoor air quality
57:47:330Michele De Carli: Good in the most critical.
57:50:200Michele De Carli: Okay? So, the fresh air will go from 1,600, okay, which was 300 times… sorry, plus… so 300 plus 500 plus 800. This is…
58:06:620Michele De Carli: the original 1,600 degree intertar, which was…
58:10:750Michele De Carli: what I was evaluating at the beginning, okay? So, based on the floor area, or on the people that are players present in the room, okay.
58:20:310Michele De Carli: I would, as first size the size to have 1,600 kilometers per hour.
58:26:740Michele De Carli: But now I have to adjust to increase by 40… by 50% this flow rate, because
58:33:610Michele De Carli: Okay, why? Because the… The recirculation is not done locally, but it's done in the area.
58:42:720Michele De Carli: So I need to keep the maximum ratio between the fresh airflow rate and the overall flow rate that I should have.
58:55:170Michele De Carli: Okay?
58:58:270Michele De Carli: Alright?
58:59:200Michele De Carli: This is general, okay? This is the general rule for
59:03:270Michele De Carli: all types of, ventilation system with recyculation, okay?
59:10:290Michele De Carli: Okay.
59:12:480Michele De Carli: Group!
59:16:420Michele De Carli: So… This is one option, okay, I told you.
59:23:700Michele De Carli: This is one option. Okay, so…
59:30:230Michele De Carli: I want to come back to this point.
59:34:710Michele De Carli: It could come.
59:37:470Michele De Carli: Okay.
59:43:330Michele De Carli: Okay, so this is… the equation.
59:48:620Michele De Carli: Okay?
59:49:880Michele De Carli: If the law is changing, you know?
59:53:290Michele De Carli: I will adjust the supply temperature, right? This is with the right call, with the…
00:01:240Michele De Carli: The, the red coils in the different zones, okay?
00:06:310Michele De Carli: I can adjust the supply temperature, and then, according to the today, today.
00:14:590Michele De Carli: the load that I need in the building, okay, I will adjust the supply temperature.
00:20:520Michele De Carli: But… I could also work with another parameter.
00:27:520Michele De Carli: Okay, so I could keep the temperature of the supply
00:32:40Michele De Carli: text, okay? So, I keep everything inside of the energy unit, and I will adjust just the flow rate.
00:41:720Michele De Carli: Okay, so in that case, I can adjust the flow rate locally, okay? How can I do that? Well, I can do that by working on local denters, okay?
00:53:830Michele De Carli: So by changing the geometry of the air terminal noise, or by having some dampers, okay, in
01:06:400Michele De Carli: some zones, okay, so I could work.
01:09:660Michele De Carli: on the air terminal analysis, or I could even work, okay, on a branch of the duct with the dampers, of course, with electric-driven
01:20:200Michele De Carli: dampers, okay, so that they can open and close, and they can adjust it for it, okay, according to the power that is needed in one room, or in one zone, okay?
01:33:940Michele De Carli: So, how can we done this? Okay, well, this is an old sketch, okay? This was done also with vendors in the media, but I told you, today is not anymore needy.
01:46:630Michele De Carli: You could use a variable speed thumb, okay? So by adjusting the voltage of the Russian engine, okay, you could adjust the speed of the thumb and thus the throwing.
02:00:390Michele De Carli: Of course!
02:02:40Michele De Carli: If you're closing, A branch somewhere.
02:07:200Michele De Carli: By closing the branch, you will increase the pressure, Okay, after they… the farm.
02:15:590Michele De Carli: So you need, okay, then to adjust the pressure, okay?
02:22:610Michele De Carli: And that is why you are, okay.
02:25:480Michele De Carli: reducing the speed of the fan. So by reducing the speed of the fan, you will reduce the flow rate, and you will keep almost
02:32:970Michele De Carli: Constant depression, okay?
02:35:770Michele De Carli: it's easier to say than do not, okay? So, usually, when you want to work with this kind of solution, okay.
02:45:850Michele De Carli: Usually, you should go by… it is usually said, you have to go by a system.
02:52:280Michele De Carli: Okay? Producer, okay?
02:55:400Michele De Carli: If you think that it is cheaper to buy the…
02:58:990Michele De Carli: Air terminal device is one side, the, the other side is on, okay?
03:05:740Michele De Carli: as someone would say, well, here in Delito, we could say the fascio Bay, fascial knee, okay, I can do it cheaper, but at the end, it will not work, okay? So you need
03:17:150Michele De Carli: I mean, what we are seeing in Bellimo, okay? Of course, Bellimo is providing the sensors, the dampers, and so on, but then the control strategy should be
03:28:470Michele De Carli: done by a unique system, okay? You need to work on a unique system. There are, okay, producers.
03:35:410Michele De Carli: And we didn't see them, okay? But, I mean, there are producers, okay? But these are specialized producers for, okay, managing everything, because it's easier… it's not that easy, okay, to…
03:51:970Michele De Carli: to balance the system in variable speed and with variable pressure, okay? Anyway, of course, the pressure, okay.
04:05:340Michele De Carli: Can't be okay.
04:08:20Michele De Carli: The best would be to look at the pressure, okay, in the most…
04:15:960Michele De Carli: distant point, okay, in order to…
04:18:980Michele De Carli: Okay? Suitable pressure, suitable flow rate in the most critical branch, okay?
04:25:310Michele De Carli: you have to think about that this is an open system, okay? So it's not a closed system as
04:31:670Michele De Carli: hydronic system, okay? With an hydronic system, you are a closed loop, okay? So, the hydronic system is secluded. In this case, you have an open system, okay? As you will see.
04:45:520Michele De Carli: You have pressure drops everywhere, including here. Okay, what do you have to do as a calculation, what you are going to do with the group work.
04:54:570Michele De Carli: Okay?
04:55:850Michele De Carli: It will be to size the system, and to calculate all the pressure losses, and to, okay, balance the system, and to size the system, okay? So, usually, the most critical point is the balance point.
05:10:460Michele De Carli: And… There, you should, okay.
05:15:410Michele De Carli: check the pressure in order to have the same pressure in… to have a stable pressure in order when you are closing one or more vendors.
05:26:790Michele De Carli: Okay? Or even opening.
05:29:980Michele De Carli: Okay, yes? This is actually done.
05:34:00Michele De Carli: He's a type of system. Yeah, it's possible.
05:39:940Michele De Carli: Right?
05:40:970Michele De Carli: But no, looking inside, some buildings over here.
05:46:700Michele De Carli: I should know it, but I told you, I didn't see neither the drawings. But I think that the hub is working like that. I'm not… I don't know exactly. I should note, not only the hub.
06:02:440Michele De Carli: What's all… Also, in other buildings.
06:07:10Michele De Carli: M1 and M2, I don't think it's… variable speed, okay? By the way, they should be retrofitted soon.
06:16:470Michele De Carli: I don't know what the soon means, but I mean, in the future, there will be… there will be. So, this is the so-called DAV, okay, variable air volume, okay? So, in this case, the volume flow rate, the flow rate of the air, okay, is,
06:34:380Michele De Carli: Is, adjust according to their…
06:37:490Michele De Carli: Power that is needed in each room, and in each room, you will… you will…
06:41:690Michele De Carli: You will tune, you will, you will, modulate the ventilation tool.
06:49:650Michele De Carli: The other option is to combine, okay.
06:54:950Michele De Carli: the, is to combine them, okay? So, you code the word
07:04:290Michele De Carli: Combine them what? The two last systems that we have seen, okay? So you could combine the variable air volume.
07:10:840Michele De Carli: with rate calls, okay, look, rate calls everywhere. And, in this case, okay, this is an example. You could work on, with the damper. You have the, the plan on, with, with the mixing.
07:28:420Michele De Carli: Right, and you have the… in this case, it's an electrical resistance, but you could think about… about…
07:35:240Michele De Carli: a water, rate coin, okay?
07:42:880Michele De Carli: I don't know if it's still available, but this site is really interesting. You can go in and from the air, for the full air system, it's very interesting. There are also
07:53:810Michele De Carli: video… there were videos, I didn't… I didn't look at that. But it's… it's very interesting, okay? You can… you can…
08:02:600Michele De Carli: So this is the generosity. In this case, you can work with the variable speed, and also with direct call. So in this case, you will have, okay, a perfect match. Why? Because, I didn't know if I mentioned it, but maybe, so…
08:21:10Michele De Carli: with the air.
08:22:420Michele De Carli: you are not able to fully close the, one branch or the air terminal devices, okay? With the air, you cannot close completely one, one branch, okay? Well, apart from
08:35:850Michele De Carli: riskier for fire safety, okay? But in this case, the system will stop, okay? But they say, you are not in unusual operating, you cannot
08:48:399Michele De Carli: Okay?
08:50:50Michele De Carli: abstract interrupted the flow rate, okay? So, whenever you are increasing the resistance by closing the surface, the crossing area, okay, you are causing some turbulences. If these turbulences become too high.
09:08:810Michele De Carli: you will generate noise, okay? So, and this noise could affect
09:13:970Michele De Carli: Comforter of the park, okay?
09:17:840Michele De Carli: So, the variable airflow rate, okay, could adjust the power in a certain room, but up to a certain limit, let's say up to 40% of the load, okay, of the room.
09:32:149Michele De Carli: sometimes 30, but not more than this. So, if you want to fine-tune the power in the room, then you could also have the rate go. So in this case, you could modulate very
09:46:520Michele De Carli: Better, okay, better the… the power that is needed in wealth.
09:52:10Michele De Carli: All right? Yes, please. I just have a question about the pressure growth in box. It's our scope to get pretty good.
09:59:350Michele De Carli: For example, if I'm gonna design the fan, I have to have external static pressure for the lux.
10:06:440Michele De Carli: You are talking about your position as AI and unit designer, or in general design?
10:12:950Michele De Carli: I think I have to get it wrong. No, usually you should… usually it works like that, okay? So, as you are going to see in the… in the, in the group work.
10:23:490Michele De Carli: The designer is responsible for everything which is from the unit to the rooms, and of course.
10:32:260Michele De Carli: the other way around from the rooms to there, and enjoy it, okay? There are two secrets.
10:37:550Michele De Carli: There are two other principles, okay? When is the word dynamic, they have a close move.
10:43:30Michele De Carli: with return, sorry, supply return, okay? But with the air, you're supplying air in the roof, so you have an open circuit, okay? And then you have the exhaust, sorry, the return, that's, okay, so you have the system to size.
10:58:630Michele De Carli: that… the… and we have one fund for…
11:04:870Michele De Carli: the supply, and one fund for the return, okay? So, the designer is responsible to provide the
11:15:50Michele De Carli: Pressure drops, okay, from the air in the unit to the buildings.
11:21:370Michele De Carli: it should also provide the drops from the air handling unit to the air intake. So, in the project that you are going to do, we are designing the whole system. The air handling unit, you, you could keep a certain therapy. In the group work, okay?
11:40:630Michele De Carli: the… you don't have to size the ARM unit, okay? You will assume a certain
11:48:610Michele De Carli: blood pressure drop head of the, of the, of the handling unit, which will be provided, okay? So…
11:56:550Michele De Carli: It would be a black box, very… Glass.
12:02:860Michele De Carli: If you don't understand, don't worry, okay? You will understand it by doing, okay? So,
12:09:850Michele De Carli: All right, so what you will have to do is to calculate all the pressure lops, okay? You will have a tool, an Excel-based tool, okay, so…
12:17:880Michele De Carli: It'd be easy.
12:21:60Michele De Carli: It will be less complicated than… you should do it by hand, okay?
12:25:520Michele De Carli: But you will see, okay? But it's good so that you can understand better. But in this case, the… what happens in the unit, of course, the air in the unit will have some localized pressure drops.
12:40:50Michele De Carli: The coils, okay, they have… they are pressure drops, okay? And these are localized pressure drops.
12:47:720Michele De Carli: 500 Pascal is reasonable.
12:50:840Michele De Carli: I don't know in the…
12:53:530Michele De Carli: In this car system, I'm working in the Imperial system. Okay. Okay. More or less, okay, this is the range, okay, I'm working at… but I mean, and then you need to supply all, okay? Okay, so…
13:11:530Michele De Carli: Then, Saran, there are… okay, so I think, I think that the hub is something like that, okay? no, I'm… I'm quite sure…
13:23:970Michele De Carli: I don't know. Anyway, it should… it should be something like that, but it will be a little bit…
13:30:240Michele De Carli: more complicated, as you will see in few slides, okay? So, not complicated, but more… At last.
13:38:430Michele De Carli: Okay, so this is variable air velocity with ray heat coils. Okay, so reheat coils and variable air velocity could, okay, modulate the power in the rooms.
13:50:630Michele De Carli: with a very good accuracy, okay? Now, I want to mention some archaeological systems, okay?
14:00:430Michele De Carli: Not because you…
14:03:450Michele De Carli: I hope you want… you won't design them, but you might meet them, okay? One is close by, okay? There, okay, so that is there. So, let's say I will try to explain a little bit this concept, and the other concept is pretty similar, okay? So, in this case.
14:21:20Michele De Carli: In order to, let's say, save, capital expenditure, the capex, okay, this is what you could do. So, basically, you have
14:32:550Michele De Carli: it's called two aquarium systems, okay? So you have a cold climate and a warm, okay? So usually, you use outdoor air.
14:42:50Michele De Carli: In winter as cold planning, and in summer as warm planning, okay? So, in winter, you have cold planning with outdoor air, you have, okay? And in the air, you are hitting the air with, with,
14:59:470Michele De Carli: And you have the warm planet, and in summer, you are cooling the humidified the air, and you add the warm air out of the
15:07:680Michele De Carli: What you do, basically, you have these dampers, okay, with an engine, okay, and they are modulating the, air coming from the
15:20:140Michele De Carli: World planning of the code plan, okay? So you can see, this is the sketch. It's interesting, because in this case, you can see the sketch. This is the duct, okay, so it's…
15:31:840Michele De Carli: it's dot, so the dot is going down, okay, below the plan, okay? And here, this is… this means that here you have a turf, okay, below the…
15:42:710Michele De Carli: the… the… the opening, okay? When you have this…
15:47:580Michele De Carli: sharing with this, with these triangles here, the sharing, or the black here, it means that you have a curve, okay, below, okay? And this, you have a curve.
15:58:740Michele De Carli: And it's going there. Then you have a plenum, a mixing platenum there, with these two dampers, and by these two dampers, you're mixing up there. Of course, from the energy point of view, this is a completely disaster, okay? But, and also it could… you could have some problems, okay, especially
16:16:400Michele De Carli: in a severe cold climate, because you could have a very cold condition here. So, anyway, this is archaeology.
16:25:210Michele De Carli: archaeology, okay? The system is pretty similar to this one, okay? This could be a very cheap solution, and a quite good solution to control the temperature to supply, in, let's say, places where
16:40:210Michele De Carli: you had the distribution, okay, in this case. In case you have to cover more distance, okay, then you could have the dots, so you could have the wrong duct and the cold duct.
16:54:310Michele De Carli: And, yeah, the mixing bag here, okay. And,
17:00:740Michele De Carli: And this is how, it works, okay? So you could… this is called dual duct systems, okay? So in this case, you have cold duct, warm duct, and you miss the air, in…
17:13:990Michele De Carli: the building, okay? Okay, now, I want to, of course… well, these are some… some pros of the system, I don't want to talk very much on that, okay? Because these are really archaeological solutions, okay?
17:31:280Michele De Carli: All right, so, last point, okay, then we, we leave, is related to the so-called
17:39:800Michele De Carli: B, C, D. Okay, so demand control ventilation. Okay, so we are seeing a variable air volume system, where the flow rate is adjusting according… is adjusted, sorry, according to the
17:55:140Michele De Carli: temperature that is needed in the room, so by the load that you need in the room, okay? So, you can have,
18:08:440Michele De Carli: The… so, the… the driver, is the load, the temperature load.
18:15:380Michele De Carli: But, you could have also, okay, you could He also added, okay.
18:22:800Michele De Carli: Des,
18:25:620Michele De Carli: Okay, so imagine that you can measure the CO2, I told you the CO2 is a good factor, okay.
18:32:590Michele De Carli: So imagine that you can have a CO2 sensor in the room, and you could decide to variable the airflow rate according either the temperature and or, okay, the air quality of the room.
18:48:190Michele De Carli: Okay, so imagine that you are here, with a variable airflow rate, we could provide a certain flow rate, but according to the people that are here, you could even decrease the
19:03:230Michele De Carli: the flow rate, okay? Perhaps by increasing with the rate called the supply temperature, okay? So, in this case, it's called demand-controlled ventilation. So, demand-controlled ventilation, it means that you borrow… you can change the flow rate
19:20:520Michele De Carli: of the air according either the sensible load or the air quality that is needed in the room, okay? The hub is, okay, working with a demand control integration, which is
19:33:900Michele De Carli: Of course, the best solution, because in this case, you could really provide the amount of fresh air which is needed just for the irrigation, in case you don't need more air, because the moon
19:50:00Michele De Carli: The set point of the set point temperature is too low in winter, too high, so…
19:56:30Michele De Carli: Okay? So, according to the level of the room, so to the… to the thermostat in the room, and to the CO2 layer that you have in your room, you can, okay, work with the… to adjust the flow rate according to both.
20:12:890Michele De Carli: systems, okay, to both controls. So what you do, you can have, okay, so of course, you need dampers, okay, so it is a variable air ventilation system, so it's completely similar to what we have seen so far, but in this case.
20:29:670Michele De Carli: It's not only driven by the temperature in the room, but also on the CO2 level in the room.
20:35:650Michele De Carli: Remember?
20:37:240Michele De Carli: As always, the… Difference between the CO2 level in the room and the outdoor.
20:43:530Michele De Carli: level of the CO2, okay? Because the… it's the difference in the CO2 measured in the room and outside, which makes the indoor air quality to be suitable. This is an example, okay?
20:58:540Michele De Carli: to explain a little bit how the demand-controlled ventilation works. In this case, it is a comparison between a constant air ventilation, CAV, okay, which is
21:15:320Michele De Carli: what we have, for instance, here in M1 and M2, right? Okay, or M9 and 10, okay, so imagine how many, lectern holes we have, and if they are…
21:29:210Michele De Carli: if they are not pretty new, okay, they're working with coastal territory. Okay, so it means that M1
21:36:980Michele De Carli: Switch this on at 7, and switches off at 7, 8, and it's working?
21:43:730Michele De Carli: Okay, full load at constant velocity, okay? And, imagine the amount of…
21:50:550Michele De Carli: energy that you need to spend, okay? For instance, consider it either the temperature or N, the inner quality. Imagine that this is, okay, the
22:07:730Michele De Carli: the needed, okay, pattern of flow rate, because you might have, anyway, some road, but, for instance, you might have
22:19:330Michele De Carli: more cloudy, okay, lectures here, or even if you think about what happens during the semester. At the beginning of the semester, the room is full, then people, okay.
22:31:510Michele De Carli: are diminished, okay? And in this case, okay, you could think about an average
22:38:40Michele De Carli: presence of people, and in this case, I want just to show you, okay, this is what you could have, for instance, okay, and…
22:46:580Michele De Carli: according to occupancy, okay, we have different patterns. And, this is, okay, this is, a study in Sweden, okay, where you could see the
23:02:70Michele De Carli: the… For instance, just the electric power, What?
23:10:310Michele De Carli: happens if you can work with… if this is the electric power that you need for the fun, okay, with the concentrated ignition system, okay?
23:22:810Michele De Carli: And this is the, okay, measured, okay, flow rates and electricity, which has been used for this demand-controlled vacation system.
23:33:330Michele De Carli: Okay, so you could see that this is, okay, the electric power that has been set. Okay, so you could see, if you make the area here, okay, so you have 25% of energy.
23:47:610Michele De Carli: That is spent by electricity compared to the fun in the constant.
23:54:660Michele De Carli: Plus, okay, the energy for the coins, and so on for the handling.
24:04:10Michele De Carli: So, which are the, which are the, Most, suitable buildings?
24:15:00Michele De Carli: Conference centers, auditorium, okay, offices, Okay, but I mean, focuses utilized better.
24:22:350Michele De Carli: with the mixed system, okay?
24:25:410Michele De Carli: Restaurants, theaters, lacking homes, okay, schools. Of course, the greater the variation of load, the energy, the energy saving, okay? This is another example, okay, this is another
24:39:230Michele De Carli: This is an office building, okay?
24:43:100Michele De Carli: Again in Sweden, I think, I remember, as far as I remember, okay? And this is, okay, what you can get. You can see, this is the,
24:53:920Michele De Carli: D.
24:55:00Michele De Carli: Cool.
24:56:50Michele De Carli: prorate, okay, this is collected part of the fund, okay, also you can see here, okay, that…
25:02:970Michele De Carli: how much energy you could save, okay? This is before renovation, okay? This is for heating supply, this is for electricity, for electricity, okay? This is after, okay, with also in the recovery unit, okay, you can…
25:18:420Michele De Carli: Okay, ever.
25:20:10Michele De Carli: Really, a pretty huge amount of energy saving, okay?
25:25:830Michele De Carli: Yeah, okay, this is another example, so this here you have some figures, okay, the average is…
25:33:230Michele De Carli: 2.6 kilowatts instead of 5.2… no, does that, I don't know.
25:41:330Michele De Carli: Alright, let me get a power of 6.5, okay. And,
25:46:100Michele De Carli: This is another example, okay, every city, okay, this is another building, okay, this is an administrative office of the university, okay, in this case, you can see the…
25:57:750Michele De Carli: They, the leaves.
26:01:310Michele De Carli: What you could.
26:03:890Michele De Carli: Yeah. The, the, what you could have, okay? So,
26:09:300Michele De Carli: Whenever you have, let's say, through your system today, okay, you should better have the map component integration, so to control
26:18:630Michele De Carli: the temperature and the indular quality, and the heat quality, okay, with the, of course, variable, because VCU is variable
26:27:310Michele De Carli: Yeah, true.
26:29:560Michele De Carli: Okay, so… we… Tomorrow?
26:36:170Michele De Carli: We go on, and we go… yeah, any unit, okay, so… We are going to go…
26:42:670Michele De Carli: Okay, thank you, and have a nice… Please.