The first experiment (Expr #1) aims to:
1- Compressor operation test with nitrogen gas instead of R-134a,
2- Make sure that the Kelvinator refrigerator is running correctly
3- Ensure that the expansion valve is compatible with the design.
Therefore, the three heat exchangers (HX-N2/N2, HX-N2/O2 main, and HX-N2/O2 2nd) will be excluded from this experiment.
In this experiment, the oxygen will not be liquefied, but only the components will be tested and designed to ensure the proper functioning of the refrigeration cycle.
The first experiment consists of a simple cycle consisting of a compressor (LR25B Laboratory) with a condenser, cooling through a Kelvinator refrigerator, and an expansion valve (taken from an LR25B Laboratory refrigerator).