2023ICERD8-C33 -- Modeling and Sizing a Compressor Test Stand for Nanolubricant Measurements PDF

Due to the rise and development of unitary heat pump and air conditioning (AC) systems as well as future implementation of newer low-GWP and HFO refrigerants and their mixtures, there is a need to understand the compressor lubricants behavior specially when mixed with nanoparticles (also called nano-lubricant) which recently showed tremendous thermophysical and tribological properties improvement. Nonetheless, the choice of compressor oil significantly impacts the efficiency of HVAC equipment, so changing compressor oil will require substantial design changes to the compressors and test environments. Therefore, a hot-gas bypass compressor test stand (CTS) can be used to test compressors utilizing nano-lubricants due to their robustness and cost-effectiveness. A thermodynamic model of the cycle was developed using Engineering Equation Solver (EES) software to design the system according to ASHRAE’s guidelines. The CTS has a design capacity of 0.5-20 tons (1.76-70 kW) compressor capacity, with design challenges including maintaining proper oil circulation with no agglomeration of nanoparticles. The CTS will be able to test the performance of various types of compressors and refrigerants at different operating conditions. These conditions will enable the optimization of the CTS with different types of nano-lubricants.