小管径管道保温材料选择研究

在保温工程中普遍地存在着这样的认识:只要保温材料足够厚,无论什么保温材料都能起到减少热量损失的作用.根据传热学原理可知,保温层厚度的确对减少热量损失有积极贡献,然而有一个前提条件就是:管道外径必须大于临界热绝缘直径.而在外部环境一定的情况下,临界热绝缘直径仅取决于保温材料的物理性质.当管道外径小于临界热绝缘直径时,管道热损失反而会增大.通过分析了保温层厚度、临界热绝缘直径与管道外径之间的关系,以及这几种关系中对管道保温的影响；并通过计算流体力学数值模拟软件——Fluent对同一管道不同保温材料进行了数值模拟且加以对比.最后得出:在管道保温,特别是对管径较小的管道进行保温时,要注意保温材料的选择.

Research the selection Of insulation material about the Small diameter pipe

There is a general cognition existing in the Insulation projection that as long as the insulation material is thick enough, insulation material would play a role in reducing heat loss. The principle of Heat Transfer shows that the thickness of the insulation layer should have a positive contribution in reducing heat loss, however, what have a prerequisite that pipe diameter must be greater than the critical heat insulation diameter. but when environment in a certain circumstances, the critical heat insulation diameter depends on the physical properties of insulation materials. When the pipe diameter less than the critical heat insulation diameter, heat loss but will increase. This paper analyzes the relationships of insulation thickness, pipe diameter and critical heat insulation diameter, and the effects on pipe insulation in these relationships; Simulating the same pipe with different insulation material and comparing them in the help of computational fluid dynamics simulation software --- Fluent. Came to the conclusion: in pipe insulation, especially for the smaller diameter pipe insulation, pay attention to the choice of insulation materials.