A Simplified Calculation Method for the Wall Temperatures of Pressure Vessels With Insulating Layers

Wall temperatures are a necessary part of the design conditions for pressure vessels. Thermal analysis by numerical simulation is widely used to compute the wall temperatures and thermal stresses of the pressure vessels, and insulation layers outside the pressure vessels are normally included in numerical models to predict more accurate results. However, modeling and meshing the insulation layers introduces more work to designers and more cost to enterprises. In this paper, a simplified calculation method for the wall temperatures of the pressure vessels with insulating layers is presented. An equivalent convective heat transfer coefficient between the outside walls of the pressure vessels and circumstances is derived by theoretical analysis, which takes into account the thermal resistances of the insulation layers and the convective heat transfer coefficient between them and the circumstances, then it can be used in numerical models of the pressure vessels without the insulation layers to compute the wall temperatures. Results of comparative analysis show that the wall temperatures of the pressure vessels by the simplified calculation method agree very well with those using the numerical simulation with the insulation layer models.