# Finding mass of working fluid needed in a thermo cycle

1. Dec 14, 2016

### FQVBSina

This question is related to a project.

I have the mass flow rate, RPM, and all other related information regarding a refrigeration cycle, does anyone have an idea on how can I estimate the total amount of working fluid I need to put into the device?

In case this comes up: the device is going to be a cooling system put in the space suit/portable life support system (PLSS) which involves long tubing around the cooling garment that circulates the cool fluid and a few more tubing plus a compressor and heat exchanger in the PLSS.

Thanks a lot!

2. Dec 16, 2016

### BvU

You'll need to integrate $\ \rho\; {\pi d^2 \over 4 } dl \$ along the length of the tubing

3. Dec 16, 2016

### Nidum

Do you have primary and secondary circuits for the refrigeration or just one circuit ?

In any case you need to allow for thermal effects and flexure .