Investigation of the Flow Field in the Pulse Tube Refrigerator with the Multi-Bypass Structure Through the Finite Element Method.

The multi-bypass structure established a radial gas channel between the regenerator and the pulse tube in the pulse tube refrigeration. Numerical results of the flow field were obtained in two dimensions by the finite element method. Afterward, the position and thermal state of selected gas parcels were tracked with the tracking algorithms. The multi-bypass structure generates vortices at the pulse tube, and the existence of these vortices inhibits the capacity of the gas parcels to take heat away from the cold end. Placing porous material near the multi-bypass structure, it could effectively reduce the vortices in the pulse tube. [ABSTRACT FROM AUTHOR]