Method for testing insulating property of textile

Abstract

A method for detecting thermal insulation property of textile product TP includes heating test plate and protective plate as well as base plate to be temperature of 16deg.c higher than ambient one by instrument, judging whether temperature difference TD between test plate and ambient is over 16 minus or plus 0.5deg.c or not and increasing or decreasing duty ratio of square wave if it is to make TD be in scope of set value, detecting actual TD between test plate and average ambient then calculating out thermal insulation index and clausius value of TP according to final duty ration of square wave and heating power of test plate.

Description

technical field [0001] The invention relates to a method for detecting the thermal insulation performance of textiles, in particular to a method for measuring the temperature difference with a constant power and calculating the thermal insulation rate, heat transfer coefficient and Cro value of textiles. Background technique [0002] At present, most domestic and foreign textile thermal insulation performance tests use flat-plate thermal instruments, and establish a detection system that can only dissipate heat upward. Heat preservation by means of electricity to obtain the start-stop rate of heating the test plate, and then use the heat transfer coefficient of the material in "Thermal Engineering": U=P / A(T p -T a ) as the basis; calculated according to the relevant formula of the textile insulation performance testing standard GB11048-89; obtain the insulation rate, heat transfer coefficient, and Cro value of the textile. The standard theoretical basis of this method is c...

AI Technical Summary

Problems solved by technology

However, serious thermal inertia problems appeared on the test board. When the sample was covered, especially when the fabric was thick, the upward heat dissipation of the test board was very slow. When the temperature reached the upper limit, even though the heating power was over, the temperature still went up——overshoot, The temperature of the test board drops very slowly, and it takes a long time to drop 0.1°C, and the amount of each overshoot is inconsistent

Similarly, when the temperature reaches the lower limit, the temperature of the test board continues to drop even though it is powered on and heated in time, and it will take a while to rise, resulting in a large duty cycle deviation. If the power-on and power-off time is directly used as the detection measurement of the instrument, the result will inevitably be large deviation

[0004] In addition, for the instruments produced by various companies, the upper and lower limits of the test plate temperature are mostly controlled from 0.1°C to 0.2°C, such as 35.9 to 36.1°C, and the temperature sensors used in the current instruments have an accuracy greater than 0.1°C. The temperature band is also one of the reasons for the inaccurate detection

[0005] Although the instrument used in the international standard ISO11092 for textile insulation performance testing adopts the method of continuous heating, it is still affected by thermal inertia, which also causes a large deviation in the test results. The standard allows a deviation of 7.5%

[0006] So far, the detection methods of fabric thermal performance all adopt the method of constant temperature difference and power measurement. Therefore, the serious influence of thermal inertia is unavoidable, and the method of detecting fabric thermal performance without the influence of thermal inertia has never been reported.

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