In this paper, the enhancement of heat transfer due to unsteady flow in channels with in-line and staggered baffles is investigated through the numerical solution of the governing unsteady fluid flow and energy equations with periodicity in the stream wise direction. For the inline configuration, the flow becomes naturally unsteady at a critical Reynolds number (Q/v) around 110. For the staggered case, this value is around 200. Significant increases in heat transfer rate are observed once the flow becomes unsteady. Results for several Reynolds numbers up to 500 are presented. The present results can be valuable to the design and operation of compact heat exchangers used in process industry.

Issue Section:
Forced Convection
Keywords:
Flow Separation, Flow Transition, Forced Convection
Topics:
Flow (Dynamics), Heat transfer, Reynolds number, Design, Flow separation, Fluid dynamics, Forced convection, Heat exchangers, Process industries, Unsteady flow
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