Method for calculating seal performance of RPV by considering material and contact nonlinearity

The invention relates to a method for calculating seal performance of an RPV (Reactor Pressure Vessel) by considering a material and contact nonlinearity. The method is used for assessing seal performance of a key structure of a serious accident mitigation technology for a nuclear power plant, and belongs to the field of in-vessel retention of molten debris. According to the method, the selection and setting of a turbulence model and an evaporation boiling model are concerned in a fluid-solid coupling calculation process; the influence of factors such as a thermal expansion coefficient of the material in a high-temperature working condition, a compression rebound curve of a gasket, the contact nonlinearity, material nonlinearity and the like on a result is comprehensively considered; and by adopting an evaluation method for a seal pressure of operation, in combination with the temperature of a dangerous contact region, an equivalent stress and a contact pressure intensity calculation result, the seal performa