保温管道表面温度和散热差异分析

Differential Analysis of Surface Temperature and Heat Dissipation of Insulation Pipes

保温工程热态验收表面热损失按二、三级测定计算时,由于不考虑辐射换热,同样保温结构的保温设备及管道采用不同黑度的保护层材料,其外表面温度及散热损失相同。表面热损失按一级测定时,由于表面换热系数计算考虑到了辐射换热,同样保温结构的保温设备及管道采用不同黑度的保护层材料,其外表面温度及散热损失也不一样,与二、三级测定相比,其测定计算值更接近实际情况。保护层材料黑度越大,散热越快,其表面温度越低;保护层材料黑度越小,散热越慢,其表面温度越高。在做保温设计时,应尽量选用黑度值低的材料做保温外护层较好,其表面散热损失较低,保温效果较好;做防烫伤设计时,采用黑度值高的材料做保温保护层较好,在同样的保温层厚度下可降低保温层外表温度,即可采用更薄的保温层厚度,节约材料,减少投资费用。

When the heat loss of thermal inspection and approval of the insulation engineering is computed using the second and third levels of measurement,the insulation equipment and pipelines of the same thermal insulation structure are not considered without taking radiation into account.The first level determines surface heat loss.Because of the surface heat exchange coefficient calculation,which takes into account radiation heat exchange,thermal insulation equipment and pipes of the same thermal insulation structure utilize various black degrees of protective layer materials.In comparison to the second and third-level measurements,the calculation value is more accurate.The higher the darkness of the protective layer,the faster it dissipates heat and the lower its surface temperature;the less blackness the protective layer,the slower the heat dissipation and the higher the surface temperature.It is preferable to utilize materials with a low black value for the insulation outer guard as much as feasible when designing the insulation.It has a low surface heat dissipation loss and a higher insulation effect;while developing an anti-scald design,a material with a high dark value is employed for insulation.The protective layer is adequate.The surface temperature of the thermal insulation layer can be reduced while maintaining the same insulation layer thickness,and a thinner thermal insulation layer thickness can be used to conserve materials.