Numerical simulation and experimental verification of a G-M type double inlet pulse tube refrigerator

Abstract

A 1-D transient numerical model has been developed to predict the performance and reveal the nonlinear dynamical characteristics of a G-M type double-inlet pulse tube refrigerator, where the oscillating amplitudes of the physical quantities are large. In this numerical simulator, governing equations consisting of the state equation, the conservation of mass and momentum in the fluid phase, as well as the energy equations for the fluid and the solid, are spatially and temporally conjugated. The boundary conditions and the initial conditions for these governing equations are discussed. The methods for the numerical discretizations of these governing equations are given. The assumption, that the refrigeration temperature at the cold-end heat exchanger is kept at a constant and known value during a cycle in the existing simulations, is released in our simulator. Instead, the refrigeration capacity is prescribed while the refrigeration temperature is determined from the numerical solution. Numerical results, such as cycle-averaged temperature distribution and fluctuations of the physical quantities in a single-stage G-M type pulse tube refrigerator, are analyzed. These numerical results are shown in good agreement with experimental data. This numerical simulator can be used not only to predict dynamical performance of a pulse tube refrigerator, but it can also be used to design a pulse tube refrigerator for optimal performance.