ABSTRACT

In this paper, an experimental investigation is conducted to investigate the cool-down behavior of single-stage Gifford-McMahon type pulse tube cryocooler. Nine different cold head configurations of pulse tube cryocooler have been fabricated with different aspect ratios of regenerator and pulse tube to investigate their effect on the cooling process. Additionally, experimental investigation have been conducted to conceive the impact of operating parameters like mean pressure, pressure ratio on minimum refrigeration temperature, and cooling capacity. The influence of orifice and double-inlet valve opening rates on the performance parameters of pulse tube cryocooler has been investigated. A transient one-dimensional computational model of the pulse tube cryocooler is adopted to predict the theoretical refrigeration performance. In the one-dimensional computational model, the governing equations for compressible flow are solved iteratively to predict the basic fluid flow and heat transfer behaviors. It is noticed that the optimum value of the orifice valve opening to achieve maximum cooling capacity and minimum refrigeration temperature strongly depends on the geometrical parameters. The minimum refrigeration temperature and maximum cooling capacity occur at different values of orifice valve opening in each configuration. The orifice valve opening is found to be a more influential parameter on cooling capacity over the double inlet valve opening.

摘要

在本文中，进行了一项实验研究，以研究单级 Gifford-McMahon 型脉冲管制冷机的冷却行为。九种不同的脉冲管制冷机冷头配置已经制造，具有不同的回热器和脉冲管纵横比，以研究它们对冷却过程的影响。此外，还进行了实验研究，以了解平均压力、压力比等操作参数对最低制冷温度和制冷量的影响。研究了孔板和双入口阀开启率对脉冲管制冷机性能参数的影响。采用脉冲管制冷机的瞬态一维计算模型来预测理论制冷性能。在一维计算模型中，迭代求解可压缩流动的控制方程以预测基本流体流动和传热行为。值得注意的是，实现最大制冷量和最低制冷温度的孔板阀开度的最佳值在很大程度上取决于几何参数。在每种配置中，最低制冷温度和最大制冷量出现在不同的孔板阀开度值处。发现孔口阀开度是比双入口阀开度对冷却能力更有影响的参数。值得注意的是，实现最大制冷量和最低制冷温度的孔板阀开度的最佳值在很大程度上取决于几何参数。在每种配置中，最低制冷温度和最大制冷量出现在不同的孔板阀开度值处。发现孔口阀开度是比双入口阀开度对冷却能力更有影响的参数。值得注意的是，实现最大制冷量和最低制冷温度的孔板阀开度的最佳值在很大程度上取决于几何参数。在每种配置中，最低制冷温度和最大制冷量出现在不同的孔板阀开度值处。发现孔口阀开度是比双入口阀开度对冷却能力更有影响的参数。