Refrigeration systems realizing L⁴; low pollution, low cost, low loss, and long life

The present work describes a refrigeration system which satisfies the criteria of L⁴: low pollution, low cost, low loss, and long life. The design closely models the Ericsson ideal gas cycle which consists of two isothermal and two constant pressure processes. The working fluid is Helium which does not change phase during the cycle. The present design uses a high frequency bellows pumping system where one bellows compartment is capable of producing 40W of cooling power. The number of compartments in the bellows pump can be customized according to the amount of power needed.