面料热阻测量在GB/T 11048新旧标准中的差异

Discrepancy between fabric thermal resistance measurements by new and old editions of GB/T 11048 standard

针对新版GB/T 11048—2008《纺织品生理舒适性稳态条件下热阻和湿阻的测定》所规定的面料热阻测量A法和B法与旧版GB/T 11048—1989《纺织品保温性能试验方法》所规定的A法进行实验对比研究。结果表明,在新版A标准下,2种型号热板仪的测量数据均值差异达31%,与热板仪的设计与校准有关;在新版A法空气层流速为1 m/s的条件下较新版B法静态空气层的条件下面料的热阻值有较大幅度的下降,其下降值不仅与面料的厚度负相关,也与面料的材料与组织结构相关,新版B法35℃对于旧版A法36℃的温度设定差异对实验结果没有显著影响,二者可直接比较;有无空气隔离罩对于新版B法的实验结果总体影响不显著,但对抑制环境空气的随机波动影响有作用。新版A法、新版B法及旧版A法的数据CV值相似,说明实验稳定性相似。新版A法与国际标准ISO11092—1993《Textiles-Physiological Effects-Measurement of Thermal and Water-Vapour Resistance Under Steady-State Conditions》一致,而新版B法与旧版A法兼容。

A study was carried out to compare fabric thermal resistance testing method A and B of the new edition of GB/T 11048-2008 ′Textiles-Physiological Effects-Measurement of Thermal and Water-Vapour Resistance Under Steady-State Conditions′ with method A of the old edition of GB/T 11048-1989 ′Textiles-testing method for warmth retention property′.Experimental results showed that in accordance with the new method A,the difference between the average values obtained from two different hot plates is up to 31%,and this may be attributed to the different design and calibration of the hot plates.The thermal resistance vale measured in accordance with new method A with air flow speed of 1 m/s is decreased significantly when compared with that in accordance with new method B with no wind,and the decline is negatively related to the thickness and also to the material and structure of fabrics.and the different temperature setting between the new method B of 35 ℃ and the old method A of 36 ℃ has no significant influence on test results,they can be compared directly;The airflow shield has no obvious effect on the overall results based on new method B,but has certain effect on the suppression of random fluctuation of ambient air disturbance.The data of CV values obtained by new method A and B and by old method A are similar,showing that these tests have similar stability.The new method A is consistent with ISO11092-1993′Textiles-Physiological Effects-Measurement of Thermal and Water-Vapour Resistance under Steady-State Conditions′,while the new method B is compatible with the old method A.