Bogerd C P, Brühwiler P A
Empa, Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Physiology and Protection, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland.
Appl Ergon. 2009 Mar;40(2):161-4. doi: 10.1016/j.apergo.2008.03.001. Epub 2008 May 2.
Heat loss of 27 full-face motorcycle helmets was studied using a thermal manikin headform. The headform was electrically heated and positioned at the exit of a wind tunnel, so that the air stream flowed onto its front side. All helmets were measured in three sessions in which all the vents were opened or closed consecutively in random order. Average heat loss was calculated from a steady state period, under controlled environmental conditions of 22+/-0.05 degrees C, 50+/-1% RH and 50.4+/-1.1 km h(-1) (14.0+/-0.3 ms(-1)) wind speed. The results show large variations in heat loss among the different helmets, ranging from 0 to 4 W for the scalp section of the headform and 8 to 18 W for the face section of the headform. Opening all the vents showed an increase in heat loss of more than 1 W (2 W) for four (two) helmets in the scalp section and six (one) helmets in the face section. These levels of heat transfer have been shown to be the thresholds for human sensitivity in scalp and face sections. Furthermore, helmet construction features which could be identified as important for heat loss of motorcycle helmets were identified.
使用热模拟人头模型研究了27款全脸摩托车头盔的热损失情况。该头模型通过电加热，并放置在风洞出口处，以便气流流向其正面。所有头盔均在三个测试环节中进行测量，在每个环节中，所有通风口以随机顺序依次打开或关闭。在22±0.05摄氏度、50±1%相对湿度和50.4±1.1千米/小时（14.0±0.3米/秒）风速的受控环境条件下，根据稳态期计算平均热损失。结果表明，不同头盔之间的热损失差异很大，头模型头皮部分的热损失范围为0至4瓦，面部部分的热损失范围为8至18瓦。对于四（两）款头盔，打开所有通风口后，头皮部分的热损失增加超过1瓦（2瓦）；对于六（一）款头盔，面部部分的热损失增加超过1瓦（2瓦）。这些热传递水平已被证明是人体头皮和面部敏感度的阈值。此外，还确定了对摩托车头盔热损失至关重要的头盔结构特征。
