为了地面模拟空间飞行器在微重力条件下的对流换热 ,抑制自然对流 ,消除或减小重力的影响 ,研究了将缩小尺寸和减小压力相结合的缩比 -减压模拟技术 ,并通过数值计算对这一技术进行了验证。研究表明 ,缩比 -减压法可以克服缩比法和减压法在应用时的不足。不论缩小尺寸和减小压力的程度如何 ,只要缩减比相等 ,自然对流的抑制效果就相同。在工程应用中 ,对一定的原型工况 ,采用缩减比参数比采用 Gr/Re2 参数更直观 ,可以指导对地面模拟实验中合适的模型尺寸和工作压力的确定 In order to simulate the convection heat transfer of the spacecraft under microgravity and to suppress the natural convection and to eliminate or reduce the influence of gravity, the reduction-compression simulation technique of reducing the size and reducing the pressure was studied. Calculations validate this technique. Research shows that the reduction - decompression method can overcome the shortcomings of the reduction ratio method and decompression method. The effect of natural convection is the same as long as the reduction ratio is equal, regardless of the degree of reduction in size and pressure. In engineering applications, the use of reduction ratio parameters is more intuitive than Gr / Re2 parameters for certain prototype conditions and can guide the determination of suitable model dimensions and working pressures in ground-based simulation experiments