Method for measuring heat conductivity of heat insulation material under different water contents

Abstract

The invention discloses a method for measuring the heat conductivity of a heat insulation material under different water contents. The method includes the steps that two identical samples are taken and dried to be absolute dry, one sample serves as a calibration sample, and the other sample serves as a sample to be measured; the sample to be measured is subjected to water absorption treatment to have a needed water content w; the heat conductivity of the calibration sample is measured through a steady state method under the mean temperature T, and a test result is recorded as lambda2; a non-steady state method is calibrated through the calibration sample and the test result lambda2 under the mean temperature T; the sample, obtained after water absorption treatment, to be measured is tested through the calibrated non-steady state method under the mean temperature T, the heat conductivity lambda (w, T) of the sample to be measured under the water content w and the mean temperature T is obtained, and measurement is completed. By means of the method for measuring the heat conductivity of the heat insulation material under the different water contents, water can be effectively restrained from migrating in the samples or dispersing outwards, and therefore it is guaranteed that the water content in the samples is uniform in measurement. The method has the advantages of being simple, high in accuracy and the like.

Description

technical field [0001] The invention relates to a method for measuring the thermal conductivity of heat insulating materials under different water content conditions. Background technique [0002] The thermal conductivity of thermal insulation materials is one of the key parameters that determine the quality of its products, so it is very important to accurately measure the thermal conductivity of materials in the quality inspection process. In the relevant national standards for the determination of thermal conductivity of thermal insulation materials, such as GB / T10294 and GB / T10295, only the influence of temperature factors on the thermal conductivity of materials is concerned, and the influence of moisture content of materials on thermal conductivity is ignored. However, in actual use, thermal insulation materials are affected by natural or unnatural factors such as weather and construction, and they themselves contain a certain amount of moisture, and there is no consen...

AI Technical Summary

Problems solved by technology

However, in actual use, thermal insulation materials are affected by natural or unnatural factors such as weather and construction, and they themselves contain a certain amount of moisture, and there is no consensus on what kind of changes the thermal conductivity of the material will cause due to the amount of moisture contained. calibration method to accurately measure

Images