In order to investigate the effects of thermodynamics on the unsteady cavitation flow of cryogenic fluid

the unsteady cavitation flow of the liquid-hydrogen around the Ogive body was studied by using the large eddy simulation under thermodynamics and isothermy. The results showed that the thermodynamics prolonged the cavitation period of liquid hydrogen

enhanced the unsteady characteristics and suppressed the cavitation. In addition

compared with isothermy

the cavitation in thermodynamics containd finer bubbles. A temperature depression about 1.5K was detected because of thermodynamics. Besides

the vortex structure moved from the cavity interface to the inner of the cavity due to the thermodynamics. The interaction between cavitation and vortex structure was also studied based on the vorticity transfer equation under thermodynamics and isothermy. In thermodynamics

the vortex stretching term is mainly located at the front and the end of the cavity

and the vortex dilation term and baroclinic torque term are mainly located inside the cavity. In isothermy

the vortex stretching term and vortex dilation term are mainly located at the interface of cavity

and the baroclinic torque term is located at the end of cavity.