Simulation of Refrigeration Cycle in Aspen HYSYS - Lecture # 4

Learn to simulate Refrigeration cycle is simulated using Aspen HYSYS. Four unit operations are simulated:
1. Compressor
2. Cooler
3. Valve
4. Heater
Problem Statement:
In a typical refrigeration system, the refrigerant (propane) starts at room temperature and ambient pressure (25 °C and 1 bar, 100 kgmole/h). It is compressed, which increases the refrigerant’s temperature and pressure, so it is a super-heated vapor (5 bar). The refrigerant is cooled by air with a fan so that it is close to room temperature. At this point, its pressure remains high and the refrigerant has been condensed to a liquid (4.9 bar). Then, the refrigerant is expanded through an expansion valve. Its pressure decreases abruptly, causing flash evaporation, which reduces the refrigerant’s temperature significantly (1.5 bar). The very cold refrigerant can then cool a fluid passed across a heat exchanger (e.g., air in an air conditioner). Of course, for an AC unit to work, the air that is used to cool down the super-heated refrigerant must be air outside of the room; the air that is cooled by the cold refrigerant is the air inside the room.
#RefrigerationCycle
#AspenHYSYS
#Compressor
#Heater

[@dailyshotofmeme]

Just now finished Lec 4
Thank you sir😇

[@mr.shaikh3768]

This is very helpful video for all chemical engg. And i hope you make p&id cannel like this

[@federicocomito6815]

thanks for the video. I have a question: by assigning the vapour fraction = 0 at the outlet of the cooler, am i assuming that the propane is at saturated liquid condition?

[@aspenchemchannel]

Yes

[@HassanRaza-qe8ls]

I want to simulate ammonia based refrigeration system, which Fluid package should I select ?

[@sachinpanwar8086]

Highly informative. Thanks

[@afridiengineer6774]

thank u so much for such amazing tutorials

[@sagarbhandari3967]

Hi...the cooler you simulated doesn't look correct practically. The propane at outlet of cooler has vapor fraction 0 and pressure 4.9 bar which brings down propane temperature to 1.2 deg c. In the last point of the problem statement you have mentioned that propane is condensed by means of air outside the room. In majority part of the world where AC is used, the atmospheric air temperature is in the range of 30-50 deg. C. Air at this temperature can't subcool propane to 1.2 deg c. If you size a heat exchanger for this condition there will be temperature cross. So I suggest to have propane vapour fraction 0 at 4.9 bar but at 35 deg c (keeping 4-5 deg c temperature approach). Please give your reply.

[@aspenchemchannel]

Sagar, this is a shortcut simulation, and you can specify only two parameters. So, you can specify 35C instead of vapor fraction.

[@hifdzantun7800]

Is this applicable to air conditioning control system?

[@صراطِمستقیم-ع9ف]

JazakAllah

[@puterissss]

Hi, can we install pid controller in this system?

[@Megatron-zq6lg]

Sir which template are you using on aspen?

[@alisattarzade5424]

Hi Sir.İ am working ethylene-polyetylene plant. We have a ethylene refrigeration cycle system.SO my question is is that heater in your system is called also evaporator?in heater propane temperature increases.But in our system for example ethylene enter into evaporator -102 degree C and out -102 degree C. Could you please explain it sir?

[@aspenchemchannel]

Yes, you can take heater as evaporator to solve your system. To get more info, please watch Lecture # 8.

[@alisattarzade5424]

@@aspenchemchannel thanks sir. Actually I meant in the evaporator only phase change occur and temperature is constant according to Temperature - Entropy diagram of vapor compression refrigeration cycle. But temperature increase in your system in the heater. Why it is like that?

[@aspenchemchannel]

@@alisattarzade5424 yes. The same exercise is carried in Video # 8, where we just varied vapor value from 0 to 1.

[@mohammeddilawar6726]

how to draw ph chart in this software plss reply??

[@sajidaarshad225]

Assalam u Alaikaum Sir
Sir question ma 5th point ma heat exchanger ko mention Kiya gya tha to ap nay heater kyo use kiya

[@aspenchemchannel]

Wsalam. Since that was the 1st part and we haven't learned heat exchanger at that point, so we used heater.

[@sajidaarshad225]

@@aspenchemchannel okay sir thank you soo much ♥️♥️♥️♥️

[@attarnaved7353]

Thank You so much sir

[@aspenchemchannel]

Thank you!

[@cenkeraktemur8181]

Lets say. you dont know about the pressure at all stages. You only know evaporator temperature, condenser temperature, refrigeration load and vapor fraction . How can I calculate in this way ?