Design of a Refrigeration Compressor Stage in R134

For this project, ADT engineers were asked to design the compressor stage using the refrigerant R134a for a cooling system.

The client is a global leader in providing customized, high performing, highly engineered cooling systems. They asked ADT to design a compressor stage of a cooling system including an impeller with splitter blades, a vaneless diffuser and a volute for a target pressure and an efficiency level of about 3 points above their existing designs. Other constraints in the design were the maximum allowable stress level and vibration constraints.

Design targets

To design a refrigeration compressor stage using R134a to improve performance of the entire stage (impeller, vaneless diffuser and volute) and to meet various flow rates and pressure ratio requirements by trimming the impeller.

Deliverables

Three sets of geometries, including the full impeller, vaneless diffuser and volute as well as meridional trimmed impeller and spanwise trimmed impellers.

Impact

State-of-the-art compressor stage and series of trimmed geometries meeting all design targets.

Fig1 Fig. 1. Flow streamlines in the compressor stage.