LAMINAR FORCED CONVECTION HEAT TRANSFER IN HELICAL COILED TUBE HEAT EXCHANGERS

Abstract

A numerical investigation of the forced convection heat transfer from vertical helical coiled tubes at various Reynolds numbers, various coil-to-tube radius ratios and non-dimensional coil pitch was studied. The particular difference in this study compared to other similar studies is the boundary conditions for the helical coil. Most studies focus on constant wall temperature or constant heat flux, whereas in this study it was a fluid-to-fluid heat exchanger. The purpose of this article is to assess the influence of the tube diameter, coil pitch and shell-side mass flow rate over the performance coefficient and on shell-side heat transfer coefficient of the heat exchanger. Different characteristic lengths were used in the Nusselt number calculations to determine which length best fits the data. It was deduced that tube diameter was best choice for the characteristic length.

Keywords

Dates

  • Submission Date2009-06-01
  • Revision Date2009-12-07
  • Acceptance Date2009-12-22

DOI Reference

10.2298/TSCI090601039M

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