Convective Thermal Analysis of a Turbulent Flow in a Pipe with Two and Three Corrugated Baffles Arranged in Overlap

Abstract

The present work is a numerical computation of steady turbulent forced convection flow and pressure drop characteristics in a two-dimensional horizontal rectangular cross section channel with isothermal walls and with two and three transverse waved baffles disposed overlapping in a channel. The fluid is considered as Newtonian, incompressible with constant properties. The governing equations are solved by the method of finite volume using the SIMPLE-algorithm, in two-dimensions with the k-e Realizable model to describe the turbulence phenomena. Air is the working fluid with the flow rate in terms of Reynolds numbers ranging from 5.000 to 20.000. The effects of baffle shape geometries as well as Reynolds numbers on the flow patterns and heat transfer performances are investigated. To understand the characteristics of thermal enhancements, the friction factors are also computed. The numerical results are validated with available flat rectangular-shaped baffle measured data and found to agree well with measurement. The computational results reveal essentially, that the shape of the baffles can alter substantially the flow and heat transfer characteristics. In general, an increase in the flow Reynolds number causes a substantial increase in the convective Nusselt number other than the pressure loss is also very important. The detailed knowledge on the flow and heat transfer distribution in this computation provides the basis for further optimization of shell-and-tube heat exchangers.