人体形状对自由对流传热传输的影响
Shri H Viswanathan1, Ankit Joshi1,2, Lyle Bartels1
1School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, United States of America.
PloS one
|February 6, 2025
概括
自由对流传热传递对于室内热舒适至关重要. 这项研究发现,身体形状的变化,如BMI,对传热系数的影响最小,支持使用平均身体模型进行评估.
科学领域:
- 建筑物理 建筑物理
- 人类热舒适度的人类热舒适度
- 热传递热量转移的方法
背景情况:
- 准确的热舒适和安全评估需要了解通过辐射和自由对流的热交换.
- 以前的研究仅为西方成年人的平均水平确定了自由对流传热传递系数.
- 身体形状的变化对自由对流热传输的影响在不同人群中仍未得到充分量化.
研究的目的:
- 为了研究身体形状变化对自由对流热传递系数的影响.
- 通过使用热模具对实验数据进行数值模型的验证.
- 评估平均身体形状模型对于热舒适度和热应力评估的适用性.
主要方法:
- 开发和验证了一个多物理数值模型与ANDI (高级牛顿动态仪器) 热模型的实验数据对比.
- 模拟的免费对流传热传递在不同的虚拟模型中,代表美国成年人身高和BMI百分点 (第1-99).
- 分析了身体质量指数 (BMI),性别,身高和自由对流传热传递系数之间的关系.
主要成果:
- 发现自由对流传热传递系数独立于人类的性别和身高.
- 随着BMI的增加,观察到热传递系数略有下降,全身不超过8%,区域变化不超过16%.
- 模型模拟显示了与实验数据的良好一致 (通常<5%的差异).
结论:
- 这些发现支持在室内热检查和过热风险评估中使用平均身体形状的普遍适用性.
- 经过验证的模型和结果为人类健康,生产力和与建筑热环境相关的福祉提供了关键的见解.
- 回归系数与自由流对流的理论相关性一致,解释了高度独立性.
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