As a natural working fluid. CO 2 is receiving more and more attention in the refrigeration. The key technology of the research of CO 2 transcritcia cycle is to improve the coefficient of performance of the system that is competitive with present conventional high performance refrigerant systems. In order to lower the throttling losses in the CO 2 transcritical cycle. https://www.aviatoresmilbstore.shop/product-category/tumblers/