Abstract：A series of refrigeration units based on the similar principles of fluid dynamics were developed to test the functions of small units,and large refrigeration units with the same model were measured by similar method in order to overcome the difficulties of laboratory performance of large refrigeration units due to its higher investment. The feasibility study of similar principles in low temperature compression refrigeration was investigated according to the results of computational model and experimental performance,the results showed that the error of the effective cooling capacity was 0. 8%,and the error between computational model COP and experimental performance was minor to 10%. The properties of prototype refrigeration units conform to the state standards strictly,and provides a reference for the development and research of similar refrigeration product.

Keyword：similarity principle;calculation model;refrigeration unit;performance test;