Numerical simulation of convergent and divergent tapered pulse tube cryocoolers and experimental verification

In this paper, two models were introduced with the governing equations to simulate two kinds of tapered pulse tube cryocoolers. The simulation results were in good agreement with the results of respective experiments. It was also found that there was an optimum cone angle for tapered pulse tube cryocooler. When the cryogenic refrigerator works with this optimum cone angle, the performance could be improved a lot, which means decreasing the lowest cooling temperature and/or increasing the cooling power.