A NUMERICAL STUDY OF FLOW AND TEMPERATURE FIELDS IN CIRCULAR TUBE HEAT EXCHANGER WITH ELLIPTIC VORTEX GENERATORS

Abstract

The two-dimensional fluid flow and heat transfer in a circular tube heat exchanger with two elliptic obstacles at the back is studied numerically. The computational domain consists of a circular tube and two elliptic obstacles that are situated after the tube, such that the angle between their centerlines and the direction of free coming flow is 45°. The numerical solution is achieved by numerical integration of full Navier-Stokes and energy equations over the computational domain, using finite volume method. The fluid flow is assumed to be laminar, incompressible and steady-state with constant thermo-physical characteristics. In this study major thermo-fluid parameters such as temperature, pressure and velocity fields as well as Nusselt number and friction factor variations are computed and some results are presented in the graphs. It is shown that using of elliptic obstacles leads to an increase in the average Nusselt number and also pressure.

Keywords

Dates

  • Submission Date2006-08-04
  • Revision Date2007-11-17
  • Acceptance Date2008-02-22

DOI Reference

10.2298/TSCI0802129M

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Volume 12, Issue 2, Pages129 -136