威尼斯娱人城官网

Title:   Resonance and transition of thermal boundary layers

Time:   10:00 to 11:30, Jan 12, 2017

Place:  F307, School of Mechanical Engineering

Speaker: Assoc. Prof. Chengwang Lei

Host:   Wang Qian, Ph.D

Abstract:

Resonance occurs when a system is excited at frequencies close to the natural frequency of the system. Resonance may take place in thermal (natural convection) boundary layers, which is the first topic of this presentation. The process of determining the natural (characteristic) frequency of a thermal boundary layer and the way of triggering resonance in the thermal boundary layer will be demonstrated. The applications of resonance for enhancing heat transfer by natural convection will also be discussed. The second topic of this presentation is about the characteristics of thermal boundary layers undergoing natural and controlled transitions. Natural transition refers to the response of thermal boundary layers to random environmental disturbances, and controlled transition refers to the response to particular modes of disturbances. Two representative modes of the controlled transition including K-type and H-type transitions will be described. The three-dimensional thermal flow structures in transitioning thermal boundary layers and their implications to heat transfer will be discussed.

Biography:

Dr Chengwang Lei obtained his Bachelor and Master degrees in Mechanical Engineering at Huazhong University of Science & Technology and a PhD degree in Civil & Resource Engineering at The University of Western Australia. He has held a number of research and academic positions across multiple disciplines and at different institutions. Presently he is an Associate Professor in Fluid Engineering in the School of Civil Engineering, The University of Sydney, Australia. Dr Lei’s research has been focused mainly on buoyancy driven flows related to energy and water with environmental and industrial applications. His research interest spans over experimental modelling, numerical simulation and analytical investigation of a wide range of fluid and thermal engineering problems. Much of his research has been funded by the Australian Research Council (ARC) through ARC Discovery Projects grants. To date Dr Lei has published over 90 refereed articles in international journals and over 70 refereed articles in conference proceedings.