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00:21:270Marco Marigo: Yeah, let's see
00:36:200Marco Marigo: you get it.
00:38:610Marco Marigo: And you already started.
00:41:930Marco Marigo: What did you say?
00:44:600Marco Marigo: Goodbye?
00:49:290Marco Marigo: Okay. I don't know if you can hear me from.
00:55:330Marco Marigo: So I wanted to come back
00:58:00Marco Marigo: to this point that we have seen last time
01:01:287Marco Marigo: before moving on to the the project to the project in detail, and
01:11:320Marco Marigo: we have seen during the previous lecture how to size
01:16:414Marco Marigo: a system. We started from the definitions of the different flow rates.
01:23:330Marco Marigo: and we will come back to it just for a while. Now, at the beginning of this lecture. So if we assume to consider
01:34:300Marco Marigo: a single zoom building, so now we are making this assumption that our building
01:41:910Marco Marigo: it's very simple, and it is just a single zone.
01:46:330Marco Marigo: And
01:51:290Marco Marigo: what we have to do, as explained previously.
02:01:970Marco Marigo: I'm just thinking to remove. Just provide this
02:10:940Marco Marigo: so that they can write on the blackboard.
02:25:990Marco Marigo: Okay, so let's make this the hypothes that we are working on a single zoom building.
02:33:450Marco Marigo: As I have explained last time for this building. In order to start with the calculation, I will have to calculate
02:44:410Marco Marigo: 3 air flow rates. The 1st one associated to the cooling.
02:49:870Marco Marigo: the second one associated to the people.
02:56:900Marco Marigo: and the 3rd one for the indirect political relations.
03:01:960Marco Marigo: Once I have defined this, I can calculator.
03:08:610Marco Marigo: The design value has. The maximum
03:15:80Marco Marigo: between the 3.
03:18:270Marco Marigo: Calculation shows that I have already done
03:21:880Marco Marigo: so once you have defined which is the design value I can decide to use 2 approaches.
03:29:190Marco Marigo: The 1st one
03:30:710Marco Marigo: is to provide to my room or to my people, because I am considering it as open so single zone
03:38:590Marco Marigo: to provide the full amount of air
03:46:890Marco Marigo: at the desired temperature, in order to provide all have the possibility in different season to provide the cooling for the heating, but for the year to provide the indoor quality issues. Okay, so what I will do is to take
04:07:850Marco Marigo: here from the outside. So
04:12:80Marco Marigo: this is the outside environment. I will take all the amount of air from here.
04:19:750Marco Marigo: I will treat and smeared and provide to the building
04:31:510Marco Marigo: very easy.
04:32:880Marco Marigo: So in this way. I'm sure that all in all the seasons I can provide the amount of energy I'm using.
04:40:530Marco Marigo: But which is the problem here is that I have
04:44:00Marco Marigo: the condition outside. For example, in cooling outdoor we will have maybe 35
04:50:500Marco Marigo: support. This is the reason, okay, if we're going to the southern part of Italy, for example.
04:55:880Marco Marigo: and whose side do you have to reach?
04:58:820Marco Marigo: The 20 or 26, according to the read, to the, to the season.
05:04:340Marco Marigo: otherwise outside they can have minus 5 or my mistake.
05:12:370Marco Marigo: So.
05:13:480Marco Marigo: taking a high volume, fluoridate of air from the outside and putting inside after the treatment means that I will need a very high power.
05:28:690Marco Marigo: So which is an alternative approach, I can see.
05:36:350Marco Marigo: Okay, if I don't want to
05:39:950Marco Marigo: have this high energy required to hear
05:44:380Marco Marigo: I can use a cycle approach.
05:57:630Marco Marigo: I can take gear from the outside
06:04:950Marco Marigo: and put inside. But I can also
06:10:370Marco Marigo: not put all the design here, like in this case.
06:17:720Marco Marigo: Okay, sign.
06:22:860Marco Marigo: But they can say, Okay, I will take just clear from indoor quality issues from the outside.
06:32:970Marco Marigo: And in order to reach a design value.
06:37:910Marco Marigo: I can click some air from inside
06:44:100Marco Marigo: and recirculator
06:51:60Marco Marigo: in this way before he had treatment.
06:57:10Marco Marigo: I will have some air that is already in indoor conditions.
07:06:350Marco Marigo: and so I will have that part of the energy that I didn't used before
07:13:20Marco Marigo: is saved, thanks to the pre-mixing of indoor air before the treatment.
07:26:170Marco Marigo: So what is happening inside the machine? In this case.
07:35:980Marco Marigo: my year ending unit is introducing some air.
07:43:110Marco Marigo: Yay, that is the design value
07:49:10Marco Marigo: from the outside. I'm just thinking
07:58:10Marco Marigo: the air associated to the indoor air quality, and all the remaining air
08:09:630Marco Marigo: is taken from the circulation
08:16:990Marco Marigo: for the mass balance.
08:22:200Marco Marigo: I can say that the design value must be equal to the reciripation plus the menu for indoor recording.
08:50:760Marco Marigo: But there is something that is still missing, and we have a problem.
08:55:390Marco Marigo: because if I come back to my environment
08:59:830Marco Marigo: I will have some design flow that is entering.
09:03:920Marco Marigo: and some recirculation air that is exiting. So what does it mean according to this equation. If this is entering.
09:13:580Marco Marigo: Yes, and this is exiting, I will have that
09:20:980Marco Marigo: if this is not 0, and it is never.
09:25:780Marco Marigo: I will also have a supply of fear
09:28:920Marco Marigo: that is higher than the extraction, so I will put
09:35:470Marco Marigo: more air inside than the quantity I extract, so what they need to do
09:42:360Marco Marigo: is to take some other air from inside and throw it outside and disease the exhaust path.
10:00:840Marco Marigo: How can I quantify the exhaust path
10:03:990Marco Marigo: if I make a mass balance of this environment, I can see that
10:15:90Marco Marigo: the exhaust path must extract the same amount, the same amount.
10:23:630Marco Marigo: The fact that I introduced here.
10:32:460Marco Marigo: Is it clear this point?
10:36:840Marco Marigo: So, if not, please, any questions.
10:50:890Marco Marigo: Yes, wrong web we are extracting from the from the where the app.
11:04:450Marco Marigo: So
11:07:160Marco Marigo: if I want to reduce this power. And this is clear. Okay, we take the air and recirculate. Okay.
11:15:220Marco Marigo: we take the air from the recirculation path, and we mix it with the air from the indoor air quality issues, because this is the only air that must comes from the outside. Okay, all the other air. Okay, the cooling of the heating can be some air from here that is cooled down or heated up once more. Okay, so this is the only amount of air that must come from the outside
11:39:840Marco Marigo: sold
11:40:990Marco Marigo: in this case, if I'm introducing some air from the internal quality and mixing with this recirculation path. Okay, I will obtain the design
11:52:160Marco Marigo: value of the mask. This is because I must fulfill this.
12:01:160Marco Marigo: Okay, so I I must fulfill always the design flow
12:08:920Marco Marigo: in order to be able to fulfilling eating and in order. So I know that for definition, this
12:16:180Marco Marigo: plus, this must be equal to the design fact.
12:19:660Marco Marigo: Okay.
12:22:360Marco Marigo: and this is what we have said here, if I take this machine. Okay, I can see that the balance inside to see that as I have some recyclation path that comes. Okay. And this mixed with the indoor quality.
12:37:660Marco Marigo: I have this requirement, this
12:40:830Marco Marigo: that is assumed from the calculation, and this is, that is the design minus the indoor activity Stoke.
13:04:120Marco Marigo: No, ace we have seen. If I am supplying some design flow rate.
13:13:280Marco Marigo: Okay.
13:14:290Marco Marigo: And I'm recirculating some. If I don't take this as control volume to make the bus mark mass balance might take the room.
13:22:760Marco Marigo: Okay, if I supply the design. And I'm extracting the recirculation.
13:28:870Marco Marigo: Okay for definition, my design will be always higher than the recirculation. As this can't be 0.
13:37:100Marco Marigo: Okay? And so I will have to think about the in additional
13:42:980Marco Marigo: path. That is, the exhaust. The exhaust is just to keep the mass balance. So I will have to take some air from the
13:51:30Marco Marigo: environment and to extract and throw away. Okay, so I'm I don't need this air anymore just in the exclusion pad. So I just have to take and throw it outside.
14:10:380Marco Marigo: Generally. Yeah, those properties located like
14:14:890Marco Marigo: the opposite side. Now we're gonna see. Yeah, now we're gonna see?
14:20:730Marco Marigo: Excuse me.
14:22:230Marco Marigo: Why, the exhaust mass flow. The exhaust is equal to the
14:27:500Marco Marigo: if we have to pick the massage, can we now put it?
14:35:920Marco Marigo: Okay. So we have taken this as control volume right? For this definition.
14:46:920Marco Marigo: We have taken this control volume for the Excel spec. Okay, to understand that we need this if we take this control volume.
14:58:500Marco Marigo: So taking inside also the machine, the indoor quality is entering and the exhaust is exiting.
15:05:600Marco Marigo: This is they must be equal, because the reciprocation is just internal to the system. Okay, something that stays inside the building.
15:13:950Marco Marigo: So the only way to balance this is to put away some air that is the same amount of air from the side.
15:29:80Marco Marigo: So we have understood these talking about single zone building.
15:39:520Marco Marigo: What we have done is to move from this
15:55:640Marco Marigo: to another, a different approach that allows you to define
16:16:670Marco Marigo: from these that are our design values. We have moved to this, so flow different path. But for each path we know which is the transformation that must be given to the air. Okay? So in your project you will have to move from this to this.
16:35:240Marco Marigo: The flow of indoor quality recirculation supply.
16:42:90Marco Marigo: Sorry.
16:43:310Marco Marigo: That's only the design, as we have always fully design
16:51:190Marco Marigo: and the exhaust that are those that were found there.
16:58:920Marco Marigo: Now, which is the problem that we have to face.
17:08:79Marco Marigo: - the problem is that we are moving from a single zone building to a multi zone.
17:27:170Marco Marigo: So what is happening is that my building is not like this anymore.
17:33:770Marco Marigo: But it is like this, this, please, and so on.
17:41:570Marco Marigo: Okay, so we are
17:43:680Marco Marigo: changing our problem. What we have talked about in the 1st cases. So with a single zone building must be the same. That is all. The
17:54:660Marco Marigo: concepts that were applied to that building must be applied also to this one.
18:00:760Marco Marigo: So what I'm I'm gonna do. I'm taking each single zone
18:11:400Marco Marigo: and so on
18:15:780Marco Marigo: for each one.
18:18:110Marco Marigo: I will have to calculate them.
18:24:190Marco Marigo: The cooling anything and the indoor quality fluorates.
18:35:40Marco Marigo: Then from this for each single zone.
18:40:470Marco Marigo: I will have to calculate all the others.
18:59:50Marco Marigo: So I'm moving from big building to a smaller one.
19:03:970Marco Marigo: So each zone. We will have all this flow path.
19:16:440Marco Marigo: But which is the problem? The problem is that as I have just one machine.
19:25:500Marco Marigo: not end, that's so scary as I have just went, one air handling unit cash.
19:35:930Marco Marigo: each room, each room. We have each phone, massive indoor air quality.
19:48:80Marco Marigo: Yeah.
19:48:890Marco Marigo: And which is the step that is useful to do like now, at this moment, for each room
19:57:140Marco Marigo: to calculate, I can see right here the value. N. Capital, M.
20:04:750Marco Marigo: Where capital M.
20:08:520Marco Marigo: He's the for Arizona.
20:13:180Marco Marigo: The Fedex e stay high state sport is also
20:19:170Marco Marigo: the indoor quality flow rate divided by the design flooring.
20:33:500Marco Marigo: Why do I need this value, because this value
20:40:230Marco Marigo: is the one that I use to set this
20:46:990Marco Marigo: okay is strictly related to the machine. How much air for indoor air quality issues.
20:54:270Marco Marigo: I must provide respect to the design one. So this value is the one that balances
21:02:240Marco Marigo: this flow with this flow, or, better, this flow with this.
21:07:920Marco Marigo: Okay, so it's a ratio that enables me to understand which is
21:14:770Marco Marigo: the setting of the fan and of all the dumpers. In order to keep here balanced
21:22:950Marco Marigo: the indoor quality with the recirculation in order to obtain the design value I want. So for this reason, as I have just one machine.
21:32:760Marco Marigo: in order to provide air to all my building.
21:36:640Marco Marigo: I will have to have just one M. Because
21:41:730Marco Marigo: the machine is strictly related to this value.
21:45:480Marco Marigo: I can't decide to have different and capital and values for each room. It is related to the machine setting.
21:54:730Marco Marigo: Okay, so we introduce this parameters.
22:00:540Marco Marigo: 1, 2, but exactly every zone building should have has a design flow.
22:14:700Marco Marigo: Okay, pardon of this design flows peace.
22:23:00Marco Marigo: The one for indoor air quality issues and part is associated to eating or pulling according to the season in which we are okay.
22:34:20Marco Marigo: so we'll have end design 3 and design tool
22:40:880Marco Marigo: M design one, and so on.
22:43:460Marco Marigo: But each
22:45:390Marco Marigo: room. We also have M. Indoor quality 3 and indoor quality 2 and m indoor quality one. So the value and design inside must have at least
22:59:100Marco Marigo: this value of air from the outside.
23:03:590Marco Marigo: Okay, and as all the values are different, I should have for each room one machine that mixes here from the outside with the circulation in a specific way for that room.
23:18:990Marco Marigo: Okay, but this is, of course, impossible, because I I would need different machines.
23:25:600Marco Marigo: So what are you doing?
23:27:690Marco Marigo: I deciding this parameter. Okay, each room. We will have
23:35:730Marco Marigo: capital. M. Parameter. Okay, it's all for the design. And we will take the maximum one.
23:42:570Marco Marigo: Okay, in order to set my machine with the maximum end value. Why the maximum? Because the maximum we fulfill this for also for the room that requires the higher amount of in order for
24:12:880Marco Marigo: okay.
24:13:930Marco Marigo: So now for each zone, I must
24:19:820Marco Marigo: take this value so as shown from the slides
24:25:310Marco Marigo: that we will take once more later.
24:29:160Marco Marigo: But I've just shown you last last time I have to recalculate the dollar quality values for all
24:37:900Marco Marigo: the rooms. Okay? So from this once, I take the maximum value.
24:47:380Marco Marigo: So from this I take the M maximum, that is the maximum of 4 them, and then from this
24:57:280Marco Marigo: I will have to recalculate
25:09:190Marco Marigo: each requirement in terms of indoor quality for each room.
25:15:60Marco Marigo: So we find that for all the rules
25:18:990Marco Marigo: these will increase except for one
25:22:140Marco Marigo: only. The one that had the the highest is the same. All the all the other will find will show increase
25:31:890Marco Marigo: in the flow of indoor point.
25:35:330Marco Marigo: What is this? Sorry is not simple.
25:43:300Marco Marigo: so at the end.
25:45:590Marco Marigo: What I will obtain for each room after this building
25:56:280Marco Marigo: needs this after the recalculation
26:04:620Marco Marigo: piece that was the same, and that before there is circulation, and the exhaust
26:13:150Marco Marigo: that has changed as this one has changed, and these are retained for each my zoom.
26:32:370Marco Marigo: And now for each thermosome there is the its own value of mass. I know how I must read here, and so on, the temperature, and so on.
26:46:210Marco Marigo: But now what we are facing is the real structure of the building.
26:52:930Marco Marigo: And so here we have another point. Another issue.
26:59:580Marco Marigo: What I should do is for each room to provide the design value, to instruct the exhaust to take the recirculation and recirculate, and so on. But this is something that is not efficient from the engineeristic point of view. So what are we doing.
27:17:420Marco Marigo: Bora?
27:20:630Marco Marigo: Residential offices, and so on. Public buildings.
27:30:900Marco Marigo: buildings that have no particular use like university, and so on.
27:35:790Marco Marigo: What we are doing is
27:44:390Marco Marigo: to make they simplify the division, we could say.
27:53:680Marco Marigo: so if this is year-ending unit, yeah, we have the one from the outside with circulations and design.
28:10:420Marco Marigo: I will provide the air
28:20:720Marco Marigo: to the clean rooms.
28:28:870Marco Marigo: I will extract it here
28:34:190Marco Marigo: in the dirty rooms.
28:40:290Marco Marigo: and I will circulate
28:49:430Marco Marigo: from the hallways.
28:54:220Marco Marigo: This is just the schematics, a very easy
28:58:530Marco Marigo: layout. Of course you will never have just desimplified layout.
29:10:950Marco Marigo: But with deducting system we have to try to follow this indicators.
29:20:810Marco Marigo: What do I mean by clean rooms. The clean rooms are, for example, bedrooms in a residential case. Bedrooms and the living rooms are considered clean rooms.
29:32:570Marco Marigo: Dirty rooms are bathrooms and kitchens.
29:38:320Marco Marigo: and there always is the onlys.
29:49:130Marco Marigo: If I'm going to an office, for example.
29:53:260Marco Marigo: I can imagine that the clean rooms, for example, are the places where people are actually working because they needed to have air, that there
30:03:780Marco Marigo: dirty rooms are always, for example, if we have some places where the material is stored, or if we have some double rooms like kitchens, and so on. We have bathrooms, of course.
30:21:830Marco Marigo: so we have to move from a theoretical approach to a practical approach which we must. It's up to you that our designers, to evaluate the end use of each room and understand if it's a clean room or a room. Also
30:39:520Marco Marigo: just a very fast mention to another point, if I'm not talking about typical buildings. But I'm talking about buildings where
30:48:700Marco Marigo: there are particular purposes, like, for example, hospitals, okay.
30:55:80Marco Marigo: rooms where there can be spread of infectious material and so on. When there are health issues in industry.
31:04:70Marco Marigo: Usually the
31:06:950Marco Marigo: what we have to change our approach, and to try to avoid recirculating from particularly dirty rules where there are for examples in hospitals.
31:20:900Marco Marigo: we try to avoid reciproating from that rules, and sometimes
31:30:350Marco Marigo: we try to unbalance the system. Have you explained the point?
31:35:60Marco Marigo: I'm balancing the air system in order to avoid the dispersion of infectious material. No, okay.
31:47:530Marco Marigo: So if there are rooms in which there isn't special infectious material there could be, it's better to put.
31:56:120Marco Marigo: It's in unbalancing in terms of masses. So
32:00:510Marco Marigo: we try to create an internal flow of air in order to avoid the stagnation, stagnant points for
32:08:730Marco Marigo: hazardous material.
32:12:280Marco Marigo: And why can't we do this? We can do this because we can expect that inside this building. Okay, we have openings
32:23:200Marco Marigo: in order to avoid up to allow air that is introduced here to move here to move here.
32:34:470Marco Marigo: then here there is a near exchange. Okay? So
32:38:520Marco Marigo: we are trying to create a flow in which here is introducing 1 point, and this is stroked, extracted in other points.
32:47:930Marco Marigo: Your purpose as a designer is to take your layout and check if all the building is
32:58:220Marco Marigo: provided with the air. There is airflow in all the buildings.
33:19:510Marco Marigo: I will, trying to unbalance his sister in order to issue data 3
33:27:342Marco Marigo: which pushes towards the resource. Exactly.
33:32:80Marco Marigo: So. I try to put exhaust in that room. Okay, and try to avoid having airflow that is exiting from that room. Okay.
33:43:750Marco Marigo: no. In the dirty space. Usually I don't have a resolution at all.
33:57:440Marco Marigo: I don't have to so exactly. It's your spot.
34:06:370Marco Marigo: Just one additional point before to move on is that sometimes
34:14:870Marco Marigo: here in these machines you also have
34:19:540Marco Marigo: a recovery system. Cross flow with exchanger, for example. Okay. And what is done is that you can take here from the exhaust.
34:29:540Marco Marigo: make any exchange before with outside. Okay.
34:40:639Marco Marigo: so recover also these.
34:44:50Marco Marigo: The heat of this
34:45:820Marco Marigo: flow rate in order to preheat this before the mixing with the recipulation. There are some machine that have both recipulation
34:55:290Marco Marigo: and heater recovery unit through a cross fluid exchanger. They are limited by some of these
35:02:580Marco Marigo: I found some some machines like this.
35:11:810Marco Marigo: Okay, if there are no questions, I go on with the slides.
35:40:00Marco Marigo: I decided to do this part
35:42:580Marco Marigo: with the blackboard, because last year most of your colleagues didn't understand this point, and in the records there were a lot of mistakes on this. So
35:52:490Marco Marigo: if this path until the design is not clear. You can ask me, and it's better for you to
36:02:570Marco Marigo: have everything very clear. Instead of making mistakes in the design of the system.
36:34:590Marco Marigo: Okay? So what we have reached waiting for the slides to come is that now we have
36:45:870Marco Marigo: our building and for each zone, okay, we know
36:51:710Marco Marigo: how much air we must provide. For example, to this. That is the living room. Okay? And then here I have a certain amount of fluoride.
37:09:140Marco Marigo: Next step that you will be asked to do, providing the the design of the system is to
37:17:630Marco Marigo: check, yep, and to size the number of ways and their position.
37:28:620Marco Marigo: So for each room.
37:38:110Marco Marigo: okay?
37:43:890Marco Marigo: But
37:47:720Marco Marigo: you can be very slow.
37:59:10Marco Marigo: I'm not spectam.
38:00:240Marco Marigo: Yeah.
38:02:30Marco Marigo: And we what to say to call it the Internet at check the zoom ecosystem.
38:19:780Marco Marigo: Thank you.
38:22:166Marco Marigo: Not enough
38:36:600Marco Marigo: oops.
38:40:50Marco Marigo: Yeah, it's
38:54:630Marco Marigo: okay.
38:56:430Marco Marigo: So now we know how much here you must provide to each environment and what we have to do in the project. It is required to size
39:07:250Marco Marigo: the number of veins for each environment.
39:11:760Marco Marigo: So the process is an interactive process
39:17:350Marco Marigo: that starts with the start and finishes with the end and not with the start. Of course
39:23:210Marco Marigo: we will have to make the hypothesis on the distance. So in each room you try
39:31:360Marco Marigo: design, which is the position of the bank. Okay, example.
39:36:500Marco Marigo: Like Lisa, you can check this distribution or decide for this distribution.
39:43:600Marco Marigo: You make the hypothesis on a distance.
39:49:840Marco Marigo: We clean the value, sir, and then I know that. Also, during the
39:58:30Marco Marigo: we can explain you this point.
40:00:910Marco Marigo: You calculate this flow. Okay from the data sheet of the producers, and then, if there is a good, just jet distribution, it is acceptable for you, and you have to decide. So which is the shape of the vent, which is the flow rate for each vent.
40:18:810Marco Marigo: as on you can do by these data sheets that we will have in the model
40:30:990Marco Marigo: pages. So, for example, you can decide this one.
40:35:230Marco Marigo: You set the room height, so, according to the room, heat
40:39:990Marco Marigo: you put here the distance of your report. So you have made a sketching. You have made the assumption of the distance.
40:50:850Marco Marigo: You select the distance here, and, as you already know, which is the flow of air
41:00:730Marco Marigo: that is written here, airflow rating, cubic meters per hour.
41:05:330Marco Marigo: You make
41:06:760Marco Marigo: you. You check the straight line that is describing your air flow rate, and you find the correct sizing
41:16:510Marco Marigo: of the vent. For example, in this case they made hypothesis of room height between 2.8 and 3.2 distance of 2.4,
41:27:260Marco Marigo: and then they found this point.
41:31:630Marco Marigo: By the choice of the point you can find here in this part of the graph. I don't know if you can see the
41:39:500Marco Marigo: yeah, yeah, you can find which is the value of L 0 point 5.
41:48:80Marco Marigo: And once you have decided which is the value of l. 0 point 5. That is, this distance.
41:55:800Marco Marigo: So the distance between the center of the vent and the end of the pro.
42:06:250Marco Marigo: the point where the throw reaches the 0 point 5 meters per second velocity.
42:12:180Marco Marigo: What does it mean to have a good chat distribution? It means that this curve must not
42:20:80Marco Marigo: touch among each other, so the vent
42:23:520Marco Marigo: flow must not be into contact, so they have to be.
42:29:250Marco Marigo: not to to close, and also that this point is not finding the wall.
42:37:880Marco Marigo: because in this way you would have some sound issues. So you have to try to design
42:45:590Marco Marigo: the position of the veins, try to check before, and then try and try and try, in order to find a good position of the vents in order to have a good air distribution, but not too close among them and not too close to the yeah.
43:03:390Marco Marigo: yeah, you can. Of course you can have. It is not a problem. Okay to have this too close to a wall. The problem is when it's too high, the velocity close to the wall.
43:19:810Marco Marigo: So at in this point you can touch the wall. I mean, here we reach the wall and we decrease down. And that's that's okay. But the point is that we don't have to
43:31:30Marco Marigo: past year. That is finding the road. Okay in order to okay.
43:40:560Marco Marigo: Now you have chosen your your machine.
43:45:270Marco Marigo: This is your supply path that rise here, for example, is very simplified, and then you have that dots are connected to each of the
43:56:830Marco Marigo: bent.
43:58:230Marco Marigo: In this case we are not using this approach.
44:04:910Marco Marigo: Rather, for example, let's make the photos here.
44:09:200Marco Marigo: I make a bigger room so that you can see right.
44:14:630Marco Marigo: This is just one room, for example, and decide this position of the room.
44:22:620Marco Marigo: This is the supply path, and we are
44:31:890Marco Marigo: okay. Reaching each single bank. So, as you know, which is the total mass fluorida
44:42:320Marco Marigo: air flow rate to be given to the room, you know, which is
44:49:130Marco Marigo: a total for one or 8, and so in each path you can know which is
44:58:220Marco Marigo: the amount of fare that flows through each single part of your system.
45:09:680Marco Marigo: As you know, the flow for each single path. Okay.
45:19:730Marco Marigo: with the dish, that is, am supply as the sun before the single pass.
45:30:910Marco Marigo: What we have to do is to fix for each part of the adapter
45:38:270Marco Marigo: the velocity that we can reach, so we don't have to go above this limit. You can see in this table we have residential public offices, industrial, and for each
45:51:100Marco Marigo: part of the ducting we don't have to exceed this velocity. These are limits, velocity for sound region, for noisy not to have too much noisy
46:01:750Marco Marigo: issues meeting by.
46:09:130Marco Marigo: So once I have the velocity in each path, in each part, the flow rate in each part.
46:18:410Marco Marigo: I can calculate in this way, which is the section of the dot
46:35:490Marco Marigo: we can have a choice. We can choose a model between them
46:40:960Marco Marigo: round shaped ducts or rectangular dots.
46:47:380Marco Marigo: The catalog says that usually round ducks are preferable because the air distribution inside is better. We have. They are lighter in terms of weight. They have less problems of loudness.
47:06:340Marco Marigo: and so on. But the problem is that they require a high volume of space to be installed. And so this is why sometimes it is necessary to move to
47:18:110Marco Marigo: square dots in the square docs. The flow is not as regular as in the
47:29:160Marco Marigo: in the wrong answer, because, of course, there are these points.
47:34:910Marco Marigo: that in which the flow is not uniform.
47:39:170Marco Marigo: If I take a section, for example. Okay.
47:42:410Marco Marigo: I have a distribution that is much
47:45:820Marco Marigo: more problematic because of some angles and so on.
47:52:260Marco Marigo: So I won't have life in simpler task.
47:55:320Marco Marigo: It flow like this. And we have a lot of problems with the boundaries button. Okay.
48:03:160Marco Marigo: so this is the choice between
48:05:790Marco Marigo: rectangular and round. But this is something that in the project you must choose. You mustn't sorry. Take into account what you must select is this one. This section is important for you.
48:22:570Marco Marigo: and then you have to calculate the pressure drop.
48:26:370Marco Marigo: So you know the section, you know.
48:29:850Marco Marigo: So the velocity side.
48:33:170Marco Marigo: You must calculate the pressure drop
48:36:470Marco Marigo: the last term. That is one that is interesting for us.
48:41:10Marco Marigo: The one associated with the friction pressure losses
48:44:860Marco Marigo: take into account continuous losses and localized losses.
48:49:430Marco Marigo: I know that I hope that all of you have
48:52:300Marco Marigo: made this calculation in the fluid mechanics fluid dynamics. Course. I don't know which which is the name.
49:02:610Marco Marigo: but as a general point, the continuous, the continuous pressure loss dropped
49:11:281Marco Marigo: occurs as the air is flowing inside the pipe
49:16:700Marco Marigo: inside the doctor, while the localized are
49:22:500Marco Marigo: according to particular points. So angles or changing section, and so on.
49:36:530Marco Marigo: You know that continuous pressure drop depends on this friction factor that can be calculated
49:44:500Marco Marigo: on the tables. There are some tables and graphs in order to calculate it.
49:49:00Marco Marigo: but then, in the equation, also the density here.
49:53:120Marco Marigo: It's velocity, and the ratio between L. And D.
50:00:10Marco Marigo: Length, pipe and diameter
50:07:250Marco Marigo: more than continuous
50:08:860Marco Marigo: pressure losses. I will go fast for me here, but I because I know that you have already seen
50:14:720Marco Marigo: the localized pressure drop depends on the velocity and on this coefficient how to set this coefficient.
50:27:260Marco Marigo: We just have to observe these tables
50:33:170Marco Marigo: in these tables for each element that you decided to put into your ducting.
50:39:920Marco Marigo: You will have, for example, this is around the curve. Okay around the curve that was radius is R,
50:50:410Marco Marigo: and you can see here that for each
50:53:560Marco Marigo: r on W. And according on the
50:57:440Marco Marigo: distance age that there is before this a value you can decide.
51:05:10Marco Marigo: You select, for example, R.
51:08:450Marco Marigo: On W equal to one, and in this you see that the coefficient is 0 point 2 3.
51:18:990Marco Marigo: So, according to the geometrical properties, characteristics of your element.
51:27:710Marco Marigo: you can choose which is the coefficient of the specific coefficient. Okay? For example, here you can see that you have an element that is
51:39:190Marco Marigo: breaking the the flow. And according to the ratio between a 0, that is the opening and the total section you can decide that you can set, which is the coefficient. So
51:53:10Marco Marigo: what you have to do in this equation is just to select the correct, coefficient according to the tables.
52:02:510Marco Marigo: And now I will show you as the last point
52:10:290Marco Marigo: which are the inputs and the output of this tool. We will provide you in order to calculate the pressure losses
52:18:410Marco Marigo: it will that would be used by yourself in a project
52:25:770Marco Marigo: in which you will have to design your system. So once you have reached this point, you already know the design, the layout, and so on.
52:35:10Marco Marigo: We will have to draw the system with this tool and calculate
52:39:940Marco Marigo: all the pressure losses, which is which will be your final output of the project.
52:47:650Marco Marigo: Okay.
52:55:410Marco Marigo: we will provide you this excel sheet. Okay.
52:59:930Marco Marigo: at the beginning the system is the or better, the sheet is white. Okay, this is a previous simulation I have carried out.
53:08:590Marco Marigo: and what you have to do 1st of all is to push system creation.
53:17:920Marco Marigo: Am I sure that I'm recording all the screen? I'm not sure about it.
53:26:810Marco Marigo: I don't know.
53:28:100Marco Marigo: Okay, system creation and the system will ask you
53:37:570Marco Marigo: which is the number of secondary ducts. So
53:41:370Marco Marigo: the hypothesis is that from here and the unit we have one main doctor, and then
53:47:530Marco Marigo: some secondary ducts that are exiting. From this
53:52:640Marco Marigo: we make an example. We put shoe
53:59:560Marco Marigo: for the 1st secondary duct, which is the number of final branches.
54:04:370Marco Marigo: True.
54:08:310Marco Marigo: for the second secondary doctor, the number of final branches is 3.
54:14:550Marco Marigo: I'm just making an example.
54:21:120Marco Marigo: What you can see here is that the system is building the layout of your supply path in this case.
54:27:920Marco Marigo: Okay?
54:30:760Marco Marigo: And then you can see that in the screen there are some pink pink points. Okay, these pink cells.
54:41:240Marco Marigo: you must select deduct the material.
54:45:680Marco Marigo: Okay, you have a list. It's up to you to decide which is the material
54:50:990Marco Marigo: we put. For example, aluminium in the second one.
54:57:950Marco Marigo: Here
55:01:910Marco Marigo: you have the base per height in millimeters or the diameter. You can select one
55:10:400Marco Marigo: or the other according to your choice. If it's round or it's squared.
55:19:810Marco Marigo: let's pick this one, for example.
55:23:670Marco Marigo: which are the other. Output the length of the secondary ductor.
55:28:200Marco Marigo: From this point to this point.
55:34:200Marco Marigo: Let's put 6 meters.
55:38:260Marco Marigo: These are will be calculated by the system.
55:41:680Marco Marigo: and then we will move to the final branch pencil
55:55:40Marco Marigo: at the end for each final branch, you will have to set the flow in cubic meters per hour. That comes from your calculation.
56:05:940Marco Marigo: 320 meters, and the length of this specific path.
56:13:800Marco Marigo: One meters.
56:20:200Marco Marigo: You will do this source for all
56:23:480Marco Marigo: the labels, for all the path, and then you press calculation.
56:30:850Marco Marigo: The problem is that. Of course I have not filled all the
56:37:360Marco Marigo: on the points, so it's better just to choose a very simple
56:48:20Marco Marigo: one, so that I can show you easily how it works.
57:09:490Marco Marigo: This is the same material.
57:25:160Marco Marigo: I press on calculations, and now it opens me this second sheet in this sheet.
57:35:164Marco Marigo: You can see that for each
57:39:430Marco Marigo: secondary duct branch one final branch, one. Okay, for each part of your duct.
57:45:540Marco Marigo: You will be asked to provide
57:49:310Marco Marigo: in this part of the table, so below the dimension.
57:54:830Marco Marigo: which is the localized pressure drop associated to this part of the duct.
58:01:880Marco Marigo: So, for example, in the secondary duct, we can make the hypothesis that we have a sharp edge cord.
58:12:170Marco Marigo: and maybe I don't know.
58:16:380Marco Marigo: 80 derivation right? It's not, of course, logical, but
58:23:960Marco Marigo: and maybe in this final branch. I can have
58:30:470Marco Marigo: an exit diffuser chronicle
58:34:970Marco Marigo: once I have selected, which are my losses, was, database is here. Okay, in the last sheet database you have
58:46:540Marco Marigo: with also the details, the geometrical.
58:51:480Marco Marigo: Okay, I start with the pressure drop calculation
58:56:970Marco Marigo: at the end. What the system gives you back is
59:01:820Marco Marigo: the epsilon value for this specific part of the duct, the localized pressure drop
59:09:240Marco Marigo: 0 point 8 1 Pascal. The continuous pressure drop.
59:14:80Marco Marigo: and at the end you can see localized is this one. This is continue. Okay, epsilon.
59:21:550Marco Marigo: And at the end I have a very low flow rate. But this is the pressure drop calculated for this
59:29:500Marco Marigo: range.
59:31:280Marco Marigo: Okay, and the outlet of each vent, you will have
59:34:800Marco Marigo: the single final pressure drop calculated for that.
59:47:620Marco Marigo: Is it clear? In this point? I think it's clear to use this.
59:57:700Marco Marigo: And so the last slide of the presentation.
00:03:80Marco Marigo: Okay, it's not the last, but
00:07:160Marco Marigo: this is just a path that I leave you in order to see which are the passages for the
00:14:922Marco Marigo: for the design of the air system.
00:18:580Marco Marigo: Oh.
00:20:490Marco Marigo: this is what we have talked about. You won't have to design to choose the machine in this case, in a real system, you should. But in this case we don't provide you any data sheet for the machine. So avoid this, and the final part of your project will be the the finish of the pressure loss. Drop calculation.
00:42:410Marco Marigo: So you will be divided into groups of 3 people. You already know it, and you already know your group.
00:50:410Marco Marigo: Each group will receive a specific case study, and you will have to size
00:56:90Marco Marigo: the fuller system with the recipulation for your kids.
00:59:840Marco Marigo: Sizing of supply path recirculation must be chosen only for the supply.
01:13:270Marco Marigo: The points that I will require are the calculation of the design and fresh flow rates, which is the methodology that I have explained you before, and which are the results.
01:24:420Marco Marigo: Choice of the event, their number and position.
01:28:970Marco Marigo: the schematic layout of the air distribution system, the position of year and reunit ended up sizing.
01:38:980Marco Marigo: and at the end of the calculation of the continuous and localized pressure losses for the guys.
01:47:954Marco Marigo: 2 more things be before I leave the floor to Professor Decarny are, pay attention.
02:00:311Marco Marigo: Well, 1st of all a technical thing.
02:03:920Marco Marigo: you must provide the excel with the calculations for all the calculations you have provided. So these 2 parts
02:12:400Marco Marigo: you must provide the excel. I must have the possibility of checking which were your calculations. And in case which were your mistakes.
02:20:420Marco Marigo: okay?
02:21:530Marco Marigo: And also you will have to give me back the excel sheet with all the calculations and the final sizing of the continuous and localized preferences.
02:34:450Marco Marigo: But the last thing that I want to to tell you is that
02:40:580Marco Marigo: at the end, for in the in the tool, as you have seen, you will find that for each
02:45:720Marco Marigo: out later you will have the pressure group start
02:50:500Marco Marigo: that is associated to that class.
02:53:420Marco Marigo: Okay, what the excel tool like take into account arc.
03:02:960Marco Marigo: You have seen. The draw is like this. You have here, have your unit, and then you are building.
03:13:310Marco Marigo: for example.
03:18:320Marco Marigo: piece, and at the end you will have
03:21:140Marco Marigo: a specific pressure drop for each branch.
03:28:950Marco Marigo: The tool doesn't take into account the pressure losses of this, the main doctor.
03:35:110Marco Marigo: Okay.
03:39:400Marco Marigo: So at the end, in this part, what I want to see if the total pressure loss, calculation.
03:53:910Marco Marigo: with the pressure loss of the main doctor, that you must calculate
04:00:20Marco Marigo: in the analytical way only for the main part lost
04:08:00Marco Marigo: the pressure loss of the tool
04:16:60Marco Marigo: last.
04:17:830Marco Marigo: There's a loss of the bank.
04:21:590Marco Marigo: Why?
04:22:760Marco Marigo: Because I'm asking you
04:25:650Marco Marigo: that in the localized pressure drop calculation of the tool you avoid the vent. Don't put in the supply. Don't put the vent.
04:41:940Marco Marigo: and for the event choose
04:44:950Marco Marigo: the value. That is the output of the design. Once you have chosen the vendor.
04:50:940Marco Marigo: Here you find the localized pressure drop.
04:54:580Marco Marigo: Okay? So in the event, put the value that you have calculated according to the
05:10:690Marco Marigo: good evening.
05:11:900Marco Marigo: I think it's all from my side. If you don't have a question.
05:16:910Marco Marigo: I had a question, yeah.
05:19:990Marco Marigo: After a branch in the future
05:24:610Marco Marigo: we have to take into account. I don't know if you have already
05:35:880Marco Marigo: for this. But yeah, this section is
05:40:120Marco Marigo: reducing as the air goes through the system. So here this section will be higher here it will be lower, and here it will be also lower. This depends on the fact that the velocity, as you have seen if you choose the velocity in the adequate way your section or the population section will present a lower section
06:03:220Marco Marigo: as the system is going on. No, I mean, after the 1st branch, they may not.
06:20:970Marco Marigo: Every time the system loses some air.
06:24:950Marco Marigo: it is changing the section of the system. So you mean, in this part, or better in
06:32:00Marco Marigo: you are talking about the difference between this section and this right? Yes, yes, of course.
06:47:900Marco Marigo: Okay. If you have any question you can ask either 1st of the Carly or
06:54:70Marco Marigo: you can contact me by email. You have my contacts and so on.
06:58:109Marco Marigo: Nope, there's 1 thing that I'm missing.
07:04:270Marco Marigo: No, no, I stay with you.
07:07:600Marco Marigo: This is the case study we will provide to you.
07:14:560Marco Marigo: Okay,
07:17:710Marco Marigo: each group will be provided. This case study. There are a lot of information. You don't need all of them, of course.
07:24:980Marco Marigo: but you will have, for example, here
07:28:360Marco Marigo: the surface, the position, the end use of the building, the height here, the window size. Okay.
07:40:940Marco Marigo: these are all the characteristics of the walls and the windows.
07:47:780Marco Marigo: and this is the schematics, the layout. Each case study will have its own layout.
07:56:803Marco Marigo: As you can see, there are not the specific dimensions of each. You will only have the surface
08:05:530Marco Marigo: of each office, try to assume which are the specific dimension.
08:11:360Marco Marigo: Most of the rooms are square. Okay? So try to size
08:19:290Marco Marigo: the length of the different walls according to the surface you have here. It's up to you. So these are not the real case studies.
08:32:970Marco Marigo: And then for each
08:35:350Marco Marigo: building. But we will provide you also for each room you have the heating peak load and the cooling pick load. You have also its variation along the ear. You can see here, with the
08:48:540Marco Marigo: the capacity for each along the ear. And this is also the monthly energy
08:58:580Marco Marigo: that are values that you are not required to use directly in the sizing process, the values that you're needed use are those with, of course, the discretization of each single room that we will provide to you. Okay, this was just to show you the Pdf. But I think it's a very easy to understand. Here you have also the occupancy. But that's okay.