Analyze the Effect of Thermal Conductivity of Cold Insulation Materials in Cryogenic Engineering

Abstract

The pipe heat transfer models were constructed, respectively, to simulate the cryogenic insulated structure, nonlinear partial differential equations was obtained considering the temperature-dependent variation in thermal conductivity of insulation materials. In order to get the temperature profile of insulation layer, Kirchhoff integral method was introduced to process, program, and iteratively calculate the simplified energy equations. The influence of heat-transfer process related to the thermal conductivities of four cold insulators was analyzed. Results indicate that phenolic foam, hydrophobic perlite, and RPUR have superior low-temperature insulation at cryogenic environment, while foam glass has better low-temperature insulation at normal temperature. The thickness of inner cryogenic-insulation layer can be reduced largely by using a multicomponent cold insulator in the discharge pipe of LNG stations, which can save both materials and costs. Meanwhile, it offers a new method to solve variable thermal conductivities.