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1.前言 为有效利用蒸汽,正确保温是必不可少的。所谓保温顾名思义是保持温度,也即尽量减少高温高压蒸汽的热损失,热能是一种势能,有温差才有利用价值,且温差越大利用效率就越高,保温材料则可抑制热能移动,维持温差。热损失造成的热污染也是污染源之一,所以产生了一个保温节能问题。 本文就有关蒸汽热设备的保温问题作一叙述。 2.保温原理 传热即热能的移动方式主要有传导、对流和辐射三种。保温材料内部的热移动,不是单一的热移动,而是这三者的组合。因此,所谓保温材料的传热系数从确切的意义上说是综合传热系数。大部分保温材料都利用空气传热系数较低这一特点,在狭小的空间内封入空气,从宏观看就是用大量闸板抑制辐射热,发挥整体绝热性能。 日本工业标准 JIS A 9501对保温材料是这样定义的:“为达保温目的所使用的材料,通常是指在一定使用温度下其传热系数在0.15W/(m·K)以下的材料”。
1. Introduction To properly use steam, proper insulation is essential. The so-called insulation as the name suggests is to maintain the temperature, that is, to minimize the heat loss of high temperature and high pressure steam, thermal energy is a potential energy, the use of temperature difference only, and the greater the temperature difference, the higher the utilization efficiency, thermal insulation material can inhibit heat movement, Temperature difference. Thermal pollution caused by heat loss is also one of the sources, so there has been a problem of energy-saving insulation. This article on the steam heat insulation equipment to make a statement. 2. Insulation principle Heat transfer means the movement of heat conduction, convection and radiation three. The thermal movement inside the insulation is not a single thermal move, but a combination of the three. Therefore, the so-called heat transfer coefficient of thermal insulation materials in the exact sense of the integrated heat transfer coefficient. Most of the insulation materials are using the characteristics of the lower heat transfer coefficient of air, enclosed in a small space of air, macroscopically is the use of a large number of gates to inhibit radiant heat, the overall adiabatic performance. The Japanese Industrial Standard JIS A 9501 defines insulation as follows: “Materials used for the purpose of insulation are generally those whose heat transfer coefficient is below 0.15 W / (m · K) at a certain service temperature.”