refrigerant mass inventory

[Mohammed Nofal]

Hi , I'm looking for calculating the refrigerant mass inventory inside the heat exchangers , simply when you calculate the mass for single phase region you need to multiply the volume by density , but in two phase region it more complicated , and i cant find a solution for two phase region , can any one help me in that ?

[nike123]

In operation, what goes in, goes out.
If you know mass flow of compressor, than same mass goes to HE and out of it, in unit of time.

What can give you rough estimate is quality of refrigerant you can obtain in log ph diagram for your system. Then you can apply that to parts of volumes in your HE.

[Magoo]

How long is a piece of string, short answer is it is difficult to calculate the system charge short of the company that set system up initially and stated the actual charge, on a name plate. Not very many actually do that unfortunately. The circulated rate is easy to calculate but the storage levels in receivers etc,. Is not that simple. The multi phases of expansion in an evaporator is dependent on manufacturers design which manufacturers will never publish, again unfortunately. BUT not too hard to calculate theoretically with actual system conditions that you have not let us know.