抑制自然对流的Gr数调整技术

为在地面模拟太空舱内的流动与换热，通过理论分析和数值模拟，讨论了通过改变Ｇｒ抑制自然对流、实现地面相似模拟的两种方法的可行性。针对均匀通风方式，用数值方法对改变压力的抑制自然对流技术进行了直观的分析，确定了均匀通风方式下用减压法能实现地面模拟的减压比。通过对减压法和缩小尺寸法这两种Ｇｒ数调整技术的分析表明，两种方法各有优缺点，因而适用于各自不同的工况。尺寸缩小后的模型的Ｎｕ数、材料、温度和湿度与原型保持一致，但需调整壁面热流；而减压法则无需缩小尺寸和热流，其缺点是当有湿源时无法保持温度和湿度。结果表明，采用６．６７ｋＰａ以下的压力，可以实现地面模拟。

Grashof number adjustment technique to suppress natural convection

In order to simulate the fluid flow and heat transfer of a space station cabin on the ground, both theoretical and numerical analysis has been carried out, and two methods to adjust the Grashof number to suppress the natural convection have been discussed. The Grashof number can be greatly reduced if the pressure in the cabin is reduced. The decompression factor has been determined for the uniform ventilation configuration to achieve ground simulation of the flow and heat transfer of the micro gravity environment. The investigation shows that either of the two Grashof number adjustment methods has its advantages and disadvantages. The size reduction method can preserve the material, temperature, humidity and Nusselt number simultaneously, but wall heat flux must be modified. The decompression method doesn't need to change the size and heat flux, but it doesn't apply to the condition when the air is humid. The numerical results show that the decompression method is suitable for ground simulation when the pressure in the module is lower than 6.67 kPa.