Heat Transfer Enhancement by an Oscillating Frequency of Vortex Generator

와류발생기의 가진 주파수에 의한 열전달 향상

  • Bang, Chang-Hoon (Department of Fire Protection Engineering, Kyungpook College) ;
  • Kim, Jung-Soo (Deagu branch, Korea Occupational Safety and Health Agency) ;
  • Yea, Yong-Taeg (Department of Mechanical Engineering, Kyungil University)
  • Published : 2006.04.30

Abstract

A Problem of low-velocity forced convection in a channel flow with heated wall is of practical importance and widely considered in the design of devices such as heat exchangers, and electronic equipments. Therefore, there is an urgent need for improving heat transfer performance of heated wall in the channel. In the present study, an oscillating vortex generator method is proposed to enhance the heat transfer in a channel. In this method, a rectangular bars are set in the upstream of heated region of the channel. The bars are forced to oscillate normal to the inflow, and then actively and largely generates transverse vortices behind the bars. As a result, this apparatus can enhance the heat transfer rates remarkably. Because of the interaction between the flow and oscillating bars, the variations of the flow and thermal fields become time-dependent state.

Keywords

References

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