Spiral Coil Inserts for Heat Transfer Enhancement in a Parallel-Plate Channel

Abstract

The flow fields and heat transfer characteristics in a parallel-plate channel with a transversely placed spiral coil insert were investigated by three-dimensional numerical simulation. The structure of multi-longitudinal-vortices (MLVs) induced by the spiral coil and the effects of MLVs on velocity and temperature fields were studied. The three-dimensional spiral coil induces a series of longitudinal vortices in the channel including leading longitudinal vortex, mainstream longitudinal vortices, near-wall longitudinal vortices, and rear central longitudinal vortex. Transport by the longitudinal vortices can increase the mass exchange between the boundary layer and the mainstream, which speeds up the heat migration from the channel walls and enhances the heat diffusion in the mainstream.

Acknowledgments

Wei Li obtained his Ph.D. with Dr. Ralph Webb. He would like to dedicate this work to the memory of Dr. Ralph Webb.

Notes

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