Abstract: To study the temperature transfer laws of the air clearance space of the geotechnical model box in the hyper gravity field for design of the hyper gravity test platform tests in cold regions, the convection heat transfer model for clearance soil is established. Based on the Rayleigh-Benard convection model and the CFD numerical simulation, the effects of different clearance thicknesses and hypergravity acceleration on the temperature distribution on the soil surface and inside the clearance in the hypergravity environment are studied, and the phenomenon of the cause and development of the vortex ring in the convection heat transfer process is explained. The results show that the stable distribution of the vortex ring is directly related to the flow velocity, pressure, heat transfer coefficient of interface and temperature. The Nusselt number decreases with time under different clearances and overloads. In the start-up stage of the flow field, the Nusselt number changes greatly. In different gap states, the interfacial convective heat transfer decreases with the increase of the hypergravity acceleration. The influences of the hypergravity on the thermal convection in the slit are obtained, which can be used for the experimental design in the hypergravity field to consider the comprehensive influences of the slit scale and the hypergravity acceleration.