Numerical Thermal Performance Analysis of Different Shapes of Fiber-Glass/Talc-Epoxy Insulated Cryotanks

Abstract

This study focuses on the thermal performance of different shapes of fibre-glass/talc-epoxy insulated cryotank with the aim of minimizing heat leakage into the stored cryogenic fluid. Numerical simulations were performed using a computational fluid dynamics software on rectangular-, cylindrical-, and spherical-shaped cryotank geometries while maintaining a constant inner shell volume. The outer shell was subjected to a temperature boundary condition of 28°C, while the inner shell volume was initially set to a temperature of -196°C, which is equivalent to the temperature of liquid nitrogen. The heat transfer from the environment to the cryogenic fluid stored within the cryotank was analysed numerically, and the optimal insulation thickness that minimizes the heat flux into the different cryotank shapes was determined. The results obtained revealed that the spherical-shaped cryotank exhibited had the best performance in minimizing heat leakage with the lowest temperature of -156.1°C and optimum insulation thickness of 279 mm after 3 hours of storage within the tank. Optimizing the insulation thickness was required to determine the minimum thickness required to maintain liquid nitrogen at approximately -196°C after one hour of storage. This was determined to be 240 mm, 180 mm and 160 mm for the rectangular-, cylindrical- and spherical-shaped cryotanks respectively.  This study validates the importance of optimization studies in the design of smaller and more compact cryotanks while ensuring material cost savings. This study validates the importance of numerical investigation and optimization in the design of small and compact cryotanks to ensure material cost savings without compromising thermal performance.