The calculation of the heat transfer coefficient from the walls and pipes of thermal networks in the environment

Abstract

A simple semi-analytical method for determining the heat transfer coefficient from cylindrical surfaces is proposed. The idea of the method is based on the representation of the heat wave and the self-similar nature of the process, which allows to obtain an analytical formula. The physical explanation of heat transfer coefficient decrease is given. A comparison of the approximate solution with the numerical solution of the heat propagation problem shows the high accuracy of the analytical formula. The distribution of heat from the pipe into the cold surrounding space at large times with high accuracy can be considered a self-similar process.