小管道基准保温层厚度的提出及其计算

Derivation of Benchmark Thickness of Insulator for Small Diameter Piping

基于牛顿(Newton)冷却定律,推导出了圆形管道的热流损失数学模型,介绍了基于该模型的临界保温层半径的理论推导。并在此基础上,提出了一个全新的概念——"基准保温层厚度(δj)",即敷设保温层与不敷设保温层(裸管)热流损失相当时,对应的保温层厚度。推导得出了δj满足的数学方程,并基于计算程序得到了其数值解。其结果对工农业生产或日常生活中的小直径体保温(隔热)有着重要的指导意义。

Mathematical model for the heat loss of insulated circular pipe was deduced from Newton＇s cooling equation. And a formulation is developed for its critical insulation radius, which is based on the model. Based on a further study, a new concept of ＂ bench- mark insulation layer thickness （δj） ＂ , namely the thickness that of heat loss under the conditions of taking insulation and non - insula- tion is the same, is proposed in this paper. The mathematical equations of δj is developed through theoretical derivation, and its numerical solution is obtained based on a computer calculation procedure. The results of this study are vital significance for insulation of the small diameter pipes used in agricultural production or daily life.