金属反射式保温块隔热性能的数值计算

金属反射式保温块是一种非均质的保温材料,它既有空气的导热,自然对流,反射箔的导热和辐射换热,又有外壳端、侧板的金属导热.这是一个复杂的三维传热问题.本文提出了简化模型,从而可按二维问题近似处理.同时介绍了用有限差分法进行数值计算的方法,编制了金属反射式保温块隔热性能的计算机程序.该程序具有一定的通用性,它不仅能迅速、方便地计算现有保温块的隔热性能,而且能计算各种物理、几何参数以及工作条件对隔热性能的影响,从而为合理设计这种新型保温块提供可靠的依据.

Nuerimcal Analysis of Thermal Insulation Performance of Metallic Reflective Insulator

The metallic reflective insulator is a kind of non-homogeneous thermal insulation material. There are different heat transfer mechanisms inside the insulator, including heat conduction and convection of the air, heat conduction and radiation of the reflection sheets, and heat conduction of side plate of the metal shell. This is a complex problem concerning three dimensional heat transfer. A simplified model is proposed so that the problem can be approximately dealt with by two-dimension analysis. At the same time, this paper presents the numerical analysis by means of the finite difference method. A computer program on the thermal insulation performance of the metallic reflective insulator has been worked out. There is some generality with this program. It can be used readily and conveniently to calculate not only the performance of the insulators in current use but also the effects of various properties, geometrical parameters and operating conditions on the insulation performance. Therefore, it provides a sound basis for designing new insulators.