Formula to determine Temperature after EEV (electronic expansion valve)
Formula to determine Temperature after EEV (electronic expansion valve)
(OP)
Good morning all together,
I have an issue with determining the temperature after an EEV (electronic expansion valve). I am trying to build a modell of a refrigerant circuit for simulation purposes, the information I have so far are:
- Temperature (Input)
- Pressure (Input)
- Mass flow (Input)
- Pressure (Output)
- Mass flow (Output)
I have already read a lot in this forum but haven't found a solution, that is suitable for my case. For example: "thread124-86992: CALCULATING TEMPERATURE DECREASE IN EXPANSION VALVE: CALCULATING TEMPERATURE DECREASE IN EXPANSION VALVE", or "thread378-301968: Formula for temperature change of liquid through a valve: Formula for temperature change of liquid through a valve".
I think the simplification to think of the valve throttling as an isenthalpic process is legitimate but it does not help me because the spec. heat c is dependent upon the temperature, so correctly it is c(T). Therefore there are still two unknown values.
I hope that I made my question clear enough and I'm looking forward for your help.
Thanks in advance!
I have an issue with determining the temperature after an EEV (electronic expansion valve). I am trying to build a modell of a refrigerant circuit for simulation purposes, the information I have so far are:
- Temperature (Input)
- Pressure (Input)
- Mass flow (Input)
- Pressure (Output)
- Mass flow (Output)
I have already read a lot in this forum but haven't found a solution, that is suitable for my case. For example: "thread124-86992: CALCULATING TEMPERATURE DECREASE IN EXPANSION VALVE: CALCULATING TEMPERATURE DECREASE IN EXPANSION VALVE", or "thread378-301968: Formula for temperature change of liquid through a valve: Formula for temperature change of liquid through a valve".
I think the simplification to think of the valve throttling as an isenthalpic process is legitimate but it does not help me because the spec. heat c is dependent upon the temperature, so correctly it is c(T). Therefore there are still two unknown values.
I hope that I made my question clear enough and I'm looking forward for your help.
Thanks in advance!





RE: Formula to determine Temperature after EEV (electronic expansion valve)
RE: Formula to determine Temperature after EEV (electronic expansion valve)
As suggested, you may need to lower your expectations and provide this temp drop manually by referring to established mollier curves, else you may need medication to recover from this trauma.
RE: Formula to determine Temperature after EEV (electronic expansion valve)
Thanks a lot for your detailed answer. I see that this problem is well known, good to know that others had their problems here as well ;)
Btw, I've seen people quoting the Perry Chem Engg Handbook a lot of times here.. is there a digital version available?
Thanks in advance!
RE: Formula to determine Temperature after EEV (electronic expansion valve)