Unsteady flow and heat transfer in plane channels with spatially periodic vortex generators

Abstract The flow structure and heat transfer in a plane channel with periodically placed vortex generators of different forms have been investigated in the Reynolds number range corresponding to unsteady laminar and transitional flow. Numerical results from four different configurations are reported: a pair of square bars, a rectangular bar, and two different baffle arrangements. The heat transfer and pressure drop are strongly dependent on the geometry used. A wide range of geometric parameters have been computed to cover the different possibilities. The unsteady Navier–Stokes equations and the energy equation have been solved by a finite-volume code with staggered grids combined with SIMPLEC pressure correction. The velocity and temperature fields were computed. Results for the same pumping power show heat transfer enhancement by a factor larger than 3.5 in the best cases.

[1]  E. Sparrow,et al.  Fully Developed Flow and Heat Transfer in Ducts Having Streamwise-Periodic Variations of Cross-Sectional Area , 1977 .

[2]  Miles Greiner,et al.  Two Dimensional Simulations of Enhanced Heat Transfer in an Intermittently Grooved Channel , 2000, Heat Transfer: Volume 2.

[3]  S. Patankar.  Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[4]  Cristina H. Amon,et al.  Numerical and experimental studies of self-sustained oscillatory flows in communicating channels , 1992 .

[5]  M. Sen,et al.  Enhancement of heat transfer in an inviscid-flow thermal boundary layer due to a Rankine vortex , 1998 .

[6]  M. Fiebig,et al.  Vortices and Heat Transfer , 1997 .

[7]  B. Mikic,et al.  Minimum-dissipation heat removal by scale-matched flow destabilization , 1988 .

[8]  Surya Pratap Vanka,et al.  Unsteady heat transfer in baffled channels , 1996 .

[9]  A. F. Mills.  Basic Heat and Mass Transfer , 1999 .

[10]  F. Durst,et al.  Accurate computations of the laminar flow past a square cylinder based on two different methods : lattice-Boltzmann and finite-volume , 2000 .

[11]  A. Valencia.  Heat transfer enhancement due to self-sustained oscillating transverse vortices in channels with periodically mounted rectangular bars , 1999 .

[12]  E. Roberts.  A numerical and experimental study of transition processes in an obstructed channel flow , 1994, Journal of Fluid Mechanics.

[13]  J. P. V. Doormaal,et al.  ENHANCEMENTS OF THE SIMPLE METHOD FOR PREDICTING INCOMPRESSIBLE FLUID FLOWS , 1984 .

[14]  A. London,et al.  Compact heat exchangers , 1960 .