学术报告通知

报告题目：Thermal Properties of Fibrous Materials  and Clothing Comfort

报告人：Prof. Ning Pan（University of California, Davis）

时间：2018年10月25日星期四上午10:00

地点：18号楼529报告厅

主办单位：机械结构力学及控制国家重点实验室、航空宇航学院、国际合作处

报告内容简介：

Thermal properties of porous media are very important yet challenging issues, and fibrous materials contribute additional complications due to fiber shape and orientation.   Fibrous materials are composites formed by fibers, moisture and air, being of different types and states with distinctive thermal behaviors. All of these make the research of the thermal properties of the whole system complex.

For example, a piece taken from a gold nugget is still gold, possessing all the macroscopic characteristics of the gold nugget. But a fiber taken out of a cloth is no longer cloth but a single fiber. That is, there are very limited similarities between the properties of the cloth and the fiber. This reveals an intriguing thermal phenomenon in clothing, that is, the seemingly disconnection between the thermal properties of a cloth and its constituent fibers.  The same (e.g., cotton) fibers can be made into a T-shirt to keep body cool in summer; or into a thick coat to keep body warm in winter, i.e., the thermal properties of the constituent fiber seem to have no effect on the thermal properties of the cloth system. We call this disconnection a non-affinity between the behaviors of the system and its constituents. Such non-affinities exist in other properties of fibrous materials as well.

Cloth is a multiphased, porous and anisotropic material system and usually in multilayers. Unlike ordinary engineering heat transfer problems, the human body acts as an internal heat source in a clothing situation, thus forming a temperature gradient between body and ambient, and the sign of this gradient often changes when ambient temperature varies.  Our body also perspires and the sweat evaporates, an effective cooling process via phase change. To bring all the variables into analysis quickly escalates into a formidable transport problem.

报告人简介：

潘宁博士，美国加州大学戴维斯分校教授，研究领域包括纤维集合体的物理和机械性能、纤维增强复合材料结构力学、纤维集合体的传递性能、人体与服装互动生物力学和物理相互作用、纳米结构材料，发表了200多篇SCI收录文章和三本著作，包括先进材料、先进能源材料、英国皇家学会会刊、美国物理评论等重要期刊，论文被引次数超过9,000次，h指数49（谷歌学术检索）。首次提出并发展纤维集合材料作为软物质的一个重要的分支；在纤维集合材料的力学、物理、生物物理等方面作出开创性工作；在与博士后的合作下，建立了多孔介质对液体、热流、电渗流等的传递性能的结构生成及Lattice Boltzmann解法；在人体与服装相互作用的生物力学和物理，服装与皮肤的微气候，皮肤反应，经皮吸收，以及热、湿、液体在服装与皮肤间的传输问题方面的研究推动了对服装物理现象和人体服装舒适性的理解和认知深度；首次建立了用模式识别来提取构成织物手感的本质特征并与人的触觉相标定的理论及数学模型；研发了一套用模式识别来提取构成织物手感的本质特征并与人的触觉相标定的快速可靠的织物舒适性测量的智能系统（PhabrOmeter®System）并在全球各大公司获得应用；设计了一种碳纳米管薄膜，通过结构与性能调控，可以用作柔性电池电极材料，研发了新型超级电容器。他是美国物理学会会士（fellow）、美国机械工程学会会士、英国皇家纺织学会会士，2001年担任美国纤维学会主席，2010年被捷克Polytechnic University of Liberec授予荣誉博士学位，受聘东华大学、天津工业大学、江南大学、清华大学的特聘教授，2005年获得美国NASA Tech Brief Nano 50 奖，2009年受邀并参加北京60周年国庆观礼。