00:02
We're looking at refrigeration, heat pump and air conditioning cycles of systems.
00:07
We have this depop compression heat pump cycle, right, using arrow 134a.
00:21
We have this, okay, that is point one.
00:31
They will now is point two prime, two prime prime and this is point two, point three exits of the condenser, point four.
00:54
The expansion valve exits inlet to the evaporator, right? now, it is the temperature atyx in degrees celsius.
01:06
There is entropy, axis in kilojou per kilogram per kilogram per kel, right this at 1 .5 bar which is 0 .15 megapa.
01:32
Yeah, at point two prime prime.
01:36
10 bar is something as a 1 megapascar.
01:42
80, mississippi region, 80 degrees celsius.
01:49
Right, so this is 32 degrees celsius.
01:58
Minus 20 degrees celsius at that point okay so if we actually are interpolate at 1 .5 1 .5 bar we interplay between 1 .4 and 1 .6 to determine 1 .5 bar so at 1 .5 bar you know have h1 0 .1 to be equal to okay give us 237 to 357 0 .05 0 .05 kilo kilo j.
02:39
Per kilogram.
02:43
It's a point one.
02:45
It goes as entropy 0 .193.
02:55
0 .93 .0 .9.
02:59
Kilojou per kilogram per kelvin.
03:01
So it goes the same unit as this one.
03:04
Alright.
03:04
So at 10 bar, 10 bar, 80 degrees celsius.
03:18
Okay? you are going to have uh okay we're going to have h2 prime prime double slash and top to be equal to 3 around 13 check it from your table of arrow 134 a right it here arrow 34a last revolution 14a you have it as 313 point 202 because it's in kilo kilo per kilogram is and you have s, you enter that point also to be equal to 1 .0 .04, 05 kilojouba kilogram per kelvin.
04:24
Okay, so at that 10, also at 10 bar, you can add the information at the saturated liquid line and paper line.
04:38
Okay.
04:39
Okay, there we have s at point a okay, we're going to have h at point three of course we know it's something as equal to hf liquid line so it's going to give us more on 5 .29 kiloj o per kilogram i'll look for h at point two so it's same as h at g as usual at bipole line z at pressure is going to give us 267.
05:17
Point a 97 kilojou per kilogram.
05:23
If we also consider hfg, okay, the difference between these two, we've just listed their values.
05:37
You're going to have this to be equal to hfg is going to give us 162 .68, 162 .68, 162 .68 per kilogram.
05:55
Then you are going to have s at 0 .3, the entropy, of course, as sg.
06:03
You give you, no, this is the same thing as sf, sorry.
06:11
S of point, s a liquid line.
06:14
If you give you 0 .38, 3 .8, kilojou per kilogram per kelvin, at point two, is the same thing as s .g.
06:34
So third before long as the four line that's where you get this of pressure so give you 0 .9 okay 043 because you per kilogram per kelvin then you can just go ahead and get a difference between these two okay okay, so you should give you a drop a 0 .5 okay to 2005 kilo five kilo per kilogram now i haven't gotten all this information you can now, we know that s at 2 prime is equal to s at 1.
07:17
So we can just look for the dryness fraction at 2 prime which is equal to s at 2 prime.
07:25
If you know now s at f, same time s at 3, sfg.
07:34
Plug in value is there.
07:35
You arrive at this to be 1 .0511, 0511.
07:43
So that's the trinous fraction of refrigerant or quality refrigerant.
07:51
So you can just get 2h2 prime using a dryness fraction times hfg plus hf.
08:09
So if you plug in values into this, you will have this to be 276.
08:17
0 .28 kilo per kilogram per kilogram as the entropy at 0 .2 prime...