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00:06:686Michele De Carli: So let's see, now the the internal games. Okay. So for the internal games, we have seen that basically. That is something that we have seen already in the
00:19:932Michele De Carli: in the introduction. Okay, of this part so basically, they they
00:29:880Michele De Carli: in this case, we have some internal gain storage factors to take into account which are basically the response of the group. They are, they are again
00:44:550Michele De Carli: considered as a function of the sorry mess of the room.
00:54:80Michele De Carli: So the same mass of the room that we consider for the solar gain. Sorry for the cooling loader
01:03:30Michele De Carli: due to solar radiation
01:05:428Michele De Carli: so, depending on the thermal capacity of the room, we will have okay, a greater or or lower slope. Okay in the
01:14:381Michele De Carli: or increase in the effect of the internal gains over the time. Let's see.
01:22:30Michele De Carli: and that will depend on the mass of the room, but also on how long the the internal gains are are lasting. Okay?
01:35:270Michele De Carli: What you should consider. The only thing that you have to take
01:39:470Michele De Carli: here. Okay, is that in this case, I mean, when we talked about the equivalent
01:49:460Michele De Carli: temperature difference. Or when we talked about today and
01:57:40Michele De Carli: factor, they're considering the aviation they are related to the each specific hour. Okay? So from 5 am. To sorry from 6 am. To 5 am. Okay.
02:09:259Michele De Carli: So they are related to a specific solar power. In this case, when we consider antenna days. Basically, they start from when the internal gain, okay is
02:22:420Michele De Carli: switching on. Okay? So when when either people enter the room or when you switch on the lighting or the PC, and so on. Okay, so that is the only difference between okay the the
02:36:730Michele De Carli: the factors, considering the storage factors, considering the internal gains compared to the others. Factors.
02:44:776Michele De Carli: Anyway, for your calculations for your record, you don't have to look at this. Okay.
02:50:840Michele De Carli: because you are considering a residential building, so it's very difficult to
02:56:60Michele De Carli: define the scheduling, or when an internal game is
03:03:80Michele De Carli: present or not. Okay. So in your case, you will consider a fixed rate of internal gains.
03:09:740Michele De Carli: usually as average, the internal gains, they are more or less
03:21:420Michele De Carli: what ice cream? Okay?
03:25:510Michele De Carli: So you can consider this as
03:28:890Michele De Carli: internally. Is not that much? Okay? But I mean, you can also increase it a little bit if you want, hopefully.
03:37:160Michele De Carli: But anyway, the internal day room by room will be
03:43:190Michele De Carli: constant all over the day. Okay? So that is because you don't know when
03:52:460Michele De Carli: we are not not requested to make this calculation in detail, because
03:59:660Michele De Carli: it's not like an office building. When you know that people enter in at 8 and get out at 6 7 pm. Okay, in your case.
04:10:90Michele De Carli: It's a residential building. So you don't know what
04:13:100Michele De Carli: is the behavior of people inside of the
04:17:620Michele De Carli: building. So what you will have to do is to consider.
04:23:440Michele De Carli: Okay, the
04:36:750Michele De Carli: so hour by hour.
04:43:590Michele De Carli: room by room, you have to calculate all their contributions. Okay, so you have to consider the ventilation.
04:53:320Michele De Carli: The conduction through windows.
04:58:720Michele De Carli: Mary Joy room by room. You have to do the calculation.
05:04:670Michele De Carli: this calculation here. Okay, so you have to consider the
05:09:790Michele De Carli: infiltration. Okay, the conduction through windows, the production through opac wards by means of the equivalent temperature difference, right?
05:24:260Michele De Carli: The solar radiation by means of the attenuation factors and the Internet.
05:40:110Michele De Carli: which are fixed. Okay?
05:42:420Michele De Carli: So you have to consider room by room, the different contributions. And you have to do the calculation hour by hour. Okay.
05:50:30Michele De Carli: from 5 am to 6 Am. Sorry from 6 am. To 5 am.
05:56:430Michele De Carli: Okay.
06:09:480Michele De Carli: Example of all of these. Okay, so
06:14:380Michele De Carli: your viral in your excel file, you have to do
06:20:940Michele De Carli: your profile okay, hour by hour.
06:23:950Michele De Carli: and that will be your the cooling load of your room.
06:28:520Michele De Carli: If you have 1, 1 will face outside right.
06:53:650Michele De Carli: The person that you have. Okay? And okay. So
06:59:10Michele De Carli: hour by hour, okay, you can
07:01:880Michele De Carli: considered. Okay, if you have one
07:05:990Michele De Carli: one wall faced outside. Okay, then, yeah, just one.
07:16:120Michele De Carli: Okay, one element to consider for windows and external wall.
07:23:60Michele De Carli: if you have more than once one one than more one day. Sorry, more than one orientation.
07:30:570Michele De Carli: a walls facing outside. Okay, then, you have to
07:34:290Michele De Carli: make your calculation for each orientation. Okay? So if you have.
07:38:900Michele De Carli: and that is what you have to
07:41:140Michele De Carli: at the end you will have, or
07:45:270Michele De Carli: new one. You will have a clean loader. Okay, profile
07:49:760Michele De Carli: the room 2. You will have another cooling load, and so on. Okay, so this is
07:56:130Michele De Carli: what you are expected to do. Okay?
07:59:368Michele De Carli: So yeah. The room. Load, one
08:03:00Michele De Carli: room, one row, 2 room 2.
08:05:430Michele De Carli: You might have load the same room 3.
08:10:840Michele De Carli: And you have to sum up hour by hour
08:14:960Michele De Carli: all the loads that you have for each room. Okay, the the peak. Okay, the maximum power
08:27:680Michele De Carli: of the world.
08:30:390Michele De Carli: Yeah, we're all maximum value that you have for the cooling load will be your pick load. Okay? So
08:39:669Michele De Carli: in each room you will have local maximum values. Local peak load. Okay, these peak loads
08:49:120Michele De Carli: are the ones that you are using for sizing this system here.
08:54:900Michele De Carli: That is not true.
08:57:900Michele De Carli: The overall peak load is the load.
09:03:730Michele De Carli: the the cooling load, or the picker load for your chiller for your machine.
09:10:470Michele De Carli: Okay, which has to cool the whole building. Okay.
09:15:770Michele De Carli: you don't have to sum up. If you look at that.
09:18:750Michele De Carli: you have that in this room. You have like 400 Watts. In this room you have 1,000 watts in this room. You have 600 watts. Okay, you can see that if you sum up them you will end up at the value of 2 or 2.1 kilowatts. Okay.
09:35:370Michele De Carli: which is too high. So if you sum up the local maximum
09:40:710Michele De Carli: that you will end up with a greater. But you it's not necessary, because usually that is why you need to do the calculation in a dynamic way, because in that way
09:51:360Michele De Carli: you are considering the contemporary effect of the different, and usually the peak loads can be different hours of the time which lead to an overall peak load, which is
10:09:540Michele De Carli: smaller than the sum of the maximum loads or the peak loads that you have local. Okay? Room by room.
10:16:610Michele De Carli: Again, the local peak loans are useful for sizing the terminal units.
10:21:990Michele De Carli: The overall peak load is useful for sizing Europe.
10:26:00Michele De Carli: The overall power needed for your people. Okay, because you will have again.
10:33:270Michele De Carli: Will you see?
10:34:510Michele De Carli: Right? Idea you really don't like.
10:37:880Michele De Carli: We need a generator system
10:48:210Michele De Carli: and main pipes, and these are size for the overall.
10:54:310Michele De Carli: Follow it.
10:59:00Michele De Carli: And then we need to go with the secondary pipes
11:12:320Michele De Carli: in the different rooms.
11:14:220Michele De Carli: And these are size for
11:20:870Michele De Carli: room by room power.
11:22:490Michele De Carli: Okay, so this is the main difference. Okay.
11:28:700Michele De Carli: next week has supposed to do okay.
11:39:370Michele De Carli: we see how to do that.
11:42:330Michele De Carli: We'll see how to disconnect the main main secret to the secondary secret.
11:49:810Michele De Carli: Okay?
11:54:520Michele De Carli: That's it.
11:55:790Michele De Carli: Okay. So that is everything. What you if you have some questions, I'm I'm available. Okay.
12:04:670Michele De Carli: But let's say that now you're able to
12:11:00Michele De Carli: calculate the power for heating and cooling
12:15:290Michele De Carli: of your house. Okay, the the great difference is that the the peak power for heating
12:20:920Michele De Carli: is being steady. State is the sum of the peak, power room by room for the cooling load. The maximum load of the room of the building
12:29:750Michele De Carli: is not the sum of their peak loads. Room value. Okay, okay. Now, just briefly, okay, about the bath.
12:48:410Michele De Carli: No, I don't want to talk about that.
12:50:520Michele De Carli: Okay.
12:52:143Michele De Carli: Just briefly, I would like just to show you how you do the calculations
12:58:410Michele De Carli: and in monthly base. So when you do the energy certificate of your building, okay? Basically, you consider an average day.
13:09:390Michele De Carli: month by month? Okay? And it is a little bit more complicated in meetings than what you do. Okay, just with the degree days. Okay?
13:20:120Michele De Carli: And for cooling. Okay, it's a little bit more complicated. And it is actually
13:27:60Michele De Carli: a rough estimation. Okay? But
13:33:490Michele De Carli: no, okay. I don't want to talk about that. Okay, anyway. So you're not requested. Okay, remember that in in the real life, when you do the calculation of the power, when you have to size and design the heating and cooling system of a house, you have then also to check what is the energy required by the heating and cooling system
13:57:810Michele De Carli: according to the your your decisions and your
14:03:630Michele De Carli: and the sizing of the system that you did.
14:08:180Michele De Carli: Now, summarizing what we have seen. Okay, basically, the
14:19:10Michele De Carli: we have seen that we can calculate the power in each room. Okay?
14:29:515Michele De Carli: Again, here we have
14:32:320Michele De Carli: 2 different approaches. Okay, one is the
14:38:386Michele De Carli: again, as we have seen, I mean, I mean similarly to what we have seen in the
14:44:50Michele De Carli: for the heating design we have, that the
14:50:220Michele De Carli: we have the possibility to have just water-based cooling.
14:54:620Michele De Carli: Okay, in this case.
14:57:244Michele De Carli: The terminal unit. Okay, usually, these are phone call units. Okay?
15:04:187Michele De Carli: The water-based cooling.
15:07:240Michele De Carli: Is. Considering the peak load that you need. So once you calculate the peak load for
15:17:13Michele De Carli: for cooling, as you are doing with the the current method. Okay.
15:22:830Michele De Carli: in this case, you had to select the terminal units like
15:28:50Michele De Carli: in this case, these ones here. Okay, so remember that this
15:33:280Michele De Carli: units here, we will see them. Okay. But anyway, they are not that different from the the ones that you see in the Rh. Rooms. Okay, they are located on the on the
15:47:690Michele De Carli: oh, man on the floor.
15:50:110Michele De Carli: But they are similar. Okay? So the the operation is similar. So they are the same family of terminal units.
15:58:810Michele De Carli: And in this case.
16:02:460Michele De Carli: or as we have here, okay, in that case, in in this case, we are in the followings. We are here okay with
16:08:890Michele De Carli: ventilation with. So we air and water. But imagine that here we have not the ducts providing ventilation. In this case we would have
16:17:70Michele De Carli: being in this case here. And here we have to select the water temperature. I want to remind you that usually
16:27:650Michele De Carli: for the water temperature, if you have, if you have a water chilled system.
16:35:970Michele De Carli: The water temperature you have that the supply water temperature to these units
16:42:60Michele De Carli: is 7 degrees C, okay, and the return temperature
16:50:840Michele De Carli: is 12. This 12 degrees. Okay? So usually for cooling your meeting, your chiller has to provide a chilled water at 7 degrees C. Okay, of course, you are
17:04:950Michele De Carli: subtracting heat to the room, to the building, okay, to the rooms.
17:09:180Michele De Carli: and that will heat up the water.
17:14:960Michele De Carli: Okay? Which will by an increase of 5 degrees. Delta. T, okay?
17:20:710Michele De Carli: And then the children will have to put down the water again. Okay, so
17:28:670Michele De Carli: which is to rely. Okay. So you will supply the the the building with the 7 degrees and the return with this
17:38:800Michele De Carli: revenue.
17:39:810Michele De Carli: Okay, these are the usual values for the temperature, including, okay.
17:47:880Michele De Carli: so usually, this is 5 degrees C,
17:51:630Michele De Carli: and so depending on that, then you will have selected the type of
17:56:50Michele De Carli: system. Okay, the unit. Okay, according to the size
17:59:890Michele De Carli: combination of video, which is basically combination of
18:05:03Michele De Carli: the characteristic of the heat transfer of the unit and the surface. Okay, the the surface
18:12:800Michele De Carli: of the heat exchanger that we have.
18:18:180Michele De Carli: So that is for water based cooling. For
18:21:70Michele De Carli: in case of this system here.
18:24:166Michele De Carli: usually, if you have a mechanical ventilation, you
18:30:735Michele De Carli: okay, yeah, we will see that in the following letter, okay? So in few slides.
18:42:344Michele De Carli: Here, usually in in the ventilation unit ventilation system.
18:50:830Michele De Carli: Usually, if you have this kind of system. You are also
18:55:927Michele De Carli: cooling, and they humidifying the air. Okay, so what is called
19:07:480Michele De Carli: handle meeting, where in Italian tracar model, right
19:24:280Michele De Carli: in Italian, in English, not split, but handle the
19:34:470Michele De Carli: and in Italy it's not. It's not a managerial area, but it's okay.
19:41:10Michele De Carli: So handle the air. So we cool and humidify the air. The air enters at 90 degrees. Okay, so that will be beneficial for our cooling load, because we
19:54:750Michele De Carli: we have the room at 26 degrees. So we have to consider which is the
20:00:997Michele De Carli: the effect of cooling. Okay, due to having air at 90 degrees.
20:07:490Michele De Carli: And then in case, and usually we have to considered also
20:12:840Michele De Carli: the cooling load. Okay, the peak load for cooling.
20:15:990Michele De Carli: Then again, we size the system the same way. Okay?
20:26:970Michele De Carli: If we have instead many people inside of the room.
20:31:750Michele De Carli: Okay, we can consider to use. And if the flow rate is so huge.
20:39:80Michele De Carli: okay, compared to the load that we have.
20:41:990Michele De Carli: Then in this case we can consider.
20:45:840Michele De Carli: Or we, we can use a full air system. Okay, full air system with the the air.
20:54:720Michele De Carli: which is, of course, entering at the lower temperature right.
21:01:60Michele De Carli: and which will cool down the room.
21:04:890Michele De Carli: so we'll have to face the let's say peak loader for cooling that you have calculated. Okay?
21:11:410Michele De Carli: And of course, then you have to consider which is the flow rate that you need. Okay, so
21:20:50Michele De Carli: you have the.
21:22:510Michele De Carli: You have to consider that in this case, as we will see in the in the
21:28:750Michele De Carli: when, we will talk about these fuller systems. Okay, when we are talking about ventilation. Usually the
21:37:210Michele De Carli: temperature of the air entering in the room
21:40:870Michele De Carli: is not, cannot be below 16 degrees. Okay. So if you have air entering through this
21:50:350Michele De Carli: in a gear. Okay, at a temperature lower than 16 degrees. You might have conversation in
22:00:270Michele De Carli: in these devices here. So in order to avoid conversation. We usually
22:05:160Michele De Carli: picks a minimum temperature of 60 degrees of the air, entering the room in summer condition, cooling condition.
22:13:720Michele De Carli: And of course, since you have
22:19:120Michele De Carli: 10 degrees temperature difference between the inlet temperature and the air temperature. You have to calculate which is the flow rate. Okay, that you need
22:30:130Michele De Carli: for pure in this room.
22:32:740Michele De Carli: and you have to compare the flow rate that has to be circulated in the room with the flow rate that you need for fresh air
22:43:350Michele De Carli: here.
22:45:360Michele De Carli: If they are similar, then you just use the fresh air.
22:50:220Michele De Carli: Okay? So if the supplier for pulling the the room is
22:58:830Michele De Carli: the same as the fresh air that you need. Okay, like these 10 meters per second, that we usually
23:05:130Michele De Carli: use for preparation. Okay, then, we just use the fresh air
23:10:220Michele De Carli: in case there is a mismatch between the fresh air and the and the air that we need for
23:16:650Michele De Carli: keeping the room at a certain temperature. Then we are going to recirculate part of this. Imagine that we need 3 times the prorate here, then the fresh air. Okay.
23:29:530Michele De Carli: then it's better to have just one
23:33:380Michele De Carli: part of ventilation as fresh air and 2 parts of ventilation which are recycling. Okay, but we will see that in
23:41:910Michele De Carli: in the next.
23:44:120Michele De Carli: In the next. Okay, okay, I think. It's all, if you have any question.
23:54:320Michele De Carli: No?
23:57:720Michele De Carli: Then you didn't start with the report. Yes, you started with the report.
24:02:650Michele De Carli: Okay, you have to start interview.
24:06:50Michele De Carli: They haven't told her you the heat recovery use for a lot more also include history.
24:15:287Michele De Carli: Yes, we will see that when we will talk about the full air system, but basically the heat recovery units. They are especially useful in heating. So when we have cold conditions in the
24:27:210Michele De Carli: in the summer, we might have some benefit, but not as much as in heating. Okay, so the heat recovery units are especially useful
24:38:490Michele De Carli: in heating rather than cooling
24:42:150Michele De Carli: the sensible, which the ones which are working with the sensible load in case of a a heat recovery unit, which is also is not only transferring heat, sensible heat from the outer flow to the from the exhaust air to the supplier, and vice versa. Okay?
25:05:370Michele De Carli: But if we can use some particular heat, exchanger heat recovery units working also on the record. Okay?
25:17:90Michele De Carli: So in case we use some microscopic materials.
25:21:120Michele De Carli: then in this case you have a lot of benefit. Okay? So it is possible to.
25:26:700Michele De Carli: if it is possible to have also a Latinent
25:31:380Michele De Carli: this recovery. That would be very beneficial for for short term.
25:36:670Michele De Carli: Okay, but we receive them
25:39:210Michele De Carli: when we will talk about the support. So this system with the air handling units. So what is how we can handle the air? We see how to recover the heat. And what kind of heat recovery units? We might.
25:51:990Michele De Carli: Okay, that is a good question.
25:55:890Michele De Carli: Okay, so no question.
26:01:940Michele De Carli: Okay. So we stop the presentation