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00:01:460Michele De Carli: Okay?
00:17:340Michele De Carli: Okay, and we talk about full air or all-air system. Okay, so we have just introduced the concept of ventilation, so we began with the…
00:31:380Michele De Carli: with the easiest solution, now go to the most complicated solution, okay, that we have, and these are the all-air, all full-air systems, okay?
00:42:330Michele De Carli: So, the all-air or full-air systems, okay, they have, of course, pros and cons, as all the solutions, okay? So, the pros are to have the possi… to have the possibility of outdoor indoor conditions, okay, so it's possible to count on the indoor
01:01:620Michele De Carli: Conditions, again, Don't you? Pussy.
01:05:30Michele De Carli: There is no piping, water piping, okay, which is, of course, a product, of course.
01:11:270Michele De Carli: You have to remember that air has a smaller density and a smaller specific heat compared to the water, which means that by, by considering the same,
01:28:310Michele De Carli: the same power to be delivered, okay, or to be carried by the air. Of course, that means that you will need larger, okay, more, volume, more, more…
01:46:370Michele De Carli: You need more volume, okay? So you need greater dots, greater sections in order to, let's say, bring power that you could do with…
01:58:310Michele De Carli: Okay?
01:59:260Michele De Carli: So, from this point of view, you have a poor energy efficiency, also because
02:08:919Michele De Carli: The farm, okay, is less…
02:12:620Michele De Carli: is less efficient than a pump, okay? So that is also one point to consider.
02:18:650Michele De Carli: And, of course, as I told you, the size of there, that's okay, they are larger than the diameters of the pipe, okay, for the water, okay.
02:29:630Michele De Carli: And, Sprague, of course.
02:33:680Michele De Carli: As we have seen, it's not complicated to have the heat recovery unit, so to recover the heat, so to have some efficiency on board of the machine.
02:42:320Michele De Carli: And what is important also is that everything, all the handling activities, so all the
02:50:10Michele De Carli: the stuff needed for Henry Mir is, is,
02:55:720Michele De Carli: Located in one position in the clear line.
02:58:800Michele De Carli: Okay, so this is the… these are the prompts. Scom, partner column for the system, okay?
03:06:510Michele De Carli: the balancing, okay? The balancing is not that easy, as you will see when you're going to size to design the large distribution system. You will see that
03:18:550Michele De Carli: Balancing the system, okay, can be tricky, okay?
03:23:780Michele De Carli: Okay, and, that's, okay.
03:31:220Michele De Carli: So, we, what we are going to see is the balance of minimum, okay, you have seen
03:44:240Michele De Carli: We spent, 3 weeks, okay, on it.
03:47:980Michele De Carli: And you know that, basically, the… when we think about an integration system, we need to consider the sensible and methodical balance, okay? So we need to consider
04:02:490Michele De Carli: The temperatures, the incoming temperatures, the temperature of the air inside of the room, the
04:11:150Michele De Carli: Unity ratio of the income near the humidity ratio of the outgoing Here.
04:16:880Michele De Carli: And of course, the load, the sensible load, and the vapor generation rate that you have inside of a room, and at the end, the specific enthalpy of the incominger
04:31:810Michele De Carli: and the air in the room. Of course, what we are going to consider, as we have done so far.
04:39:750Michele De Carli: Is that the…
04:42:970Michele De Carli: conditions of the air from the side of the room, so that when we extract the air… Sorry.
04:52:660Michele De Carli: When we start here, okay, the humid duration, the time.
05:01:490Michele De Carli: Based on the balance that we have.
05:05:950Michele De Carli: So, in principle, we can write, as you know.
05:09:760Michele De Carli: The balances, okay, this is the…
05:14:750Michele De Carli: The sensible balance, okay, so this is the heating or cooling load. This is the incoming temperature, okay, this is the air temperature, 20 in winter, 26 in summer, and we have, to define
05:30:650Michele De Carli: The income, okay, cash flow rate, okay, and this is the sensible,
05:38:450Michele De Carli: balance equation. On the other side, we have seen also the vapor balance equation, and also mass, where we have the humidity ratio difference between the resulting
05:52:150Michele De Carli: Humidity ratio here, and the incoming humidity ratio of the
05:57:860Michele De Carli: supply air, okay, we need to consider the mass balance, the mass flow rate, sorry, of the air, and the generation rate of the paper. Okay, so that is… we have seen it, okay, how to apply this.
06:13:470Michele De Carli: He said…
06:14:350Michele De Carli: This equation can be also written, okay, in power terms, okay, so we could consider this equation in terms of
06:24:250Michele De Carli: balance over and massive, they are in a power, so in this case.
06:30:850Michele De Carli: we could, of course, sum them, okay? So, if we consider the power, then we consider the R here, okay? And in this case, we will consider, so, the sum of these times
06:46:900Michele De Carli: the sum of the first equation plus the second equation times R, okay, is then the
06:55:290Michele De Carli: Sensible and latent power, okay?
06:59:710Michele De Carli: equal to the mass flow rate times the enthalpy difference between the resulting air and the incoming. Okay, so it's, it's…
07:09:340Michele De Carli: Straightforward to go to this equation.
07:12:600Michele De Carli: And what we could do, we could, in principle, divide the third equation by the second one, or the first equation divided by the third equation, okay? So we could have, then, the total load
07:30:760Michele De Carli: on the mass… Equation, okay, the vapor mass equation.
07:39:270Michele De Carli: Or we could have the sensible load.
07:42:350Michele De Carli: Divided by the total load, okay?
07:47:50Michele De Carli: So, this equation here, okay, so the ratio between the sensible load and the latent load Okay, it is…
07:55:340Michele De Carli: actually align in the psychometric chart, okay? So, what you could see here is the sensible load divided by the total load, is the inclination
08:10:900Michele De Carli: depending if it's negative or positive, it's the inclination of the line, which is told that
08:20:70Michele De Carli: Yeah, wood blocking, okay?
08:23:490Michele De Carli: And by fixing the finger condition, like A is not the temperature, but it's the inner temperature.
08:34:70Michele De Carli: By, considering the… by fixing the temperature, for instance, 20 degrees, In school, okay?
08:45:600Michele De Carli: the… this line, the blue line, okay, represents the ratio between the sensible load and the total load, okay? And it means that any point
08:59:930Michele De Carli: Now, any point on this slide?
09:02:580Michele De Carli: is a suitable point to supply the air in order to face this possible at a time. So, the whole
09:11:760Michele De Carli: the whole load of the room, okay? So, let's say to keep the root temperature, and,
09:19:120Michele De Carli: Relativity and the relative temperature, sorry, the relative humidity at 50%.
09:26:420Michele De Carli: Exactly, okay?
09:28:780Michele De Carli: Of course!
09:30:710Michele De Carli: Depending if we are going Far away, or close by, with the inlet.
09:39:500Michele De Carli: Shop?
09:46:500Michele De Carli: Okay?
09:47:420Michele De Carli: It depends, so if we… used a high delta T, okay.
09:55:20Michele De Carli: So, if we are having high density, so if we have incoming temperatures very far from air temperature.
10:04:520Michele De Carli: Let's go to the first equation here. Okay, it means…
10:08:960Michele De Carli: that fixing QR, QP, okay, so fixing the… Sensible load, okay.
10:16:400Michele De Carli: If the delta T is high, then the mass flow rate, is low. Like, so…
10:23:240Michele De Carli: It's easy. If we… if we have high values of incoming temperature, we could decrease the master rate. If we want to have
10:35:190Michele De Carli: inlet temperature close to the room temperature, then we need a larger volumetric mass flow rate, okay? And that is what we have seen, okay, when we saw the different, okay, examples, when we saw that by… if we had a small
10:52:540Michele De Carli: heating loads, we could lower the temperature in the supply, okay? When we have high sensible load, then we need to have high temperature in the supply, okay?
11:08:790Michele De Carli: Anyway, what is important is to remember that this is for the winter case. In summer, okay, we need 20… we have 26 degrees C, and this is the room condition, okay, at 50% of relative humidity.
11:24:220Michele De Carli: The ambient line, okay, is inclined in a positive way, okay, and the inlet condition could be any.
11:34:440Michele De Carli: location here, okay, but in this case, you have a limiting temperature, which is 16 degrees C, okay, because we have seen that you cannot go below 6 degrees. Okay?
11:48:950Michele De Carli: So this is a recap of what we have seen in the previous three weeks, and we are going to see, why is that okay? We are going on with the full-time system.
12:01:00Michele De Carli: Okay, so I will let you know when exactly and where to meet, okay? But, I mean, via the Prescott also, okay, it's 7.30.
12:10:730Michele De Carli: Okay, on Tuesday, okay?
12:16:250Michele De Carli: Pull dwelling, okay?