Energy recovery by means of a radial piston expander in a CO2 refrigeration system

- A radial piston expander is experimentally studied in a CO2 refrigeration cycle.
- The P-V cycle and the expander performance are measured in detail.
- An isentropic efficiency of 19% was achieved during the tests.
- By using the expander a COP improvement of 7.4% was measured.
- A COP improvement greater than 20% can be obtained with a proper design.