报告题目：New Concept of Shell Side Ammonia Direct Expansion Evaporator

报告人：Zahid Ayub

报告时间：2019年4月18日下午14：30

报告地点：Bevictor伟德官方网站D3-530会议室

主办单位：青岛科技大学机电工程学院、智能制造学院

报告人简介：

Dr. Zahid Ayub Designed and fabricated several thousand heat exchangers/pressure vessels and systems installed worldwide. He was recognized as one of the pioneers in the field of Ammonia Enhanced Heat Transfer, author of over 130 International Journal and Conference papers. He has twelve United States and International patents. He was recipient of ASHRAE Research Service Award – 2007, ASHRAE Exceptional Service Award – 2013, ASHRAE Louise and Bill Halloday Prestigious Fellow Award – 2017, ASME Heat Transfer Memorial Award (Art) – 2017. He is ASME Fellow – 1998 and ASHRAE Fellow – 2008.

报告主题：

Shell and tube heat exchangers are widely used in various industrial refrigeration systems. With recent global warming and ozone depletion concerns it is crucial to develop low charge refrigeration systems with environment friendly natural refrigerants such as ammonia. This talk presents a new concept of shell side direct expansion evaporator. Experimental and actual field data is presented with comparison to other conventional type evaporators. Experimental saturation temperature covers between -1.7ᵒC and -20ᵒC with heat flux range of 5-45 kW/m². The degree of superheat is 2-10 ᵒC. The heat transfer coefficient is observed to increase with saturation temperature and heat flux while decrease with an increase in the degree of exit superheat.