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Chapter 8

Abstract

Thermal-Hydrodynamic

in Corrugated Channels

Nabeel S. Dhaidana and Abdalrazzaq K. Abbas

other hand, the influence of the rib shapes seems to be small.

reported extensively in many articles (for example [4–8]).

rib configuration, rib shapes

1. Introduction

161

Keywords: thermal-flow performance, corrugated channel, rib distribution,

The reliable efficient heat exchangers transfer the maximum rate of heat with minimum friction losses. The rate of heat transfer of most fluids is restricted by their low thermal conductivity. Thus, the thermal systems adopt techniques of heat transfer enhancement to reduce the effect of this issue. There are three techniques of enhancing heat transfer, namely, active methods (require external power) [1], passive methods (fins, corrugation, ribs, etc.) [2], and compound techniques (simultaneous use of active and passive techniques) [3]. Corrugation of tubes and channels is considered an efficient passive method to augment the rate of heat exchange. The thermal-flow features of turbulent flow in corrugated tubes are

Corrugated channels are widely utilized in industrial applications as they are the major components in plate heat exchangers. Naphon [9] conducted experiments to

Characteristics of Turbulent Flow

The heat transfer-flow characteristics of turbulent flow inside corrugated channels heated by constant heat flux are numerically investigated. The rate of heat transfer, pressure drop, and performance evaluation criterion is determined for smooth channel and various designs of corrugated channels at the Reynolds number ranged from 5000 to 60,000. The effect of rib arrangement distributions of inward, outward, and inward-outward ribs are examined. The various rib configurations of corrugated channels are also tested. In addition, the influences of rib roughness parameters (height, pitch, and width) and rib shapes (semicircular, trapezoidal, and rectangular) are researched. The Reynolds-averaged Navier-Stokes equations (RANS) are used to model the governing flow equations. The computational model is validated through a reasonable agreement between the present numerical results and the outcomes of related works. For different geometrical and operating conditions, the results revealed that the rate of heat exchange in corrugated channels exceeds higher than that of smooth ones but with additional pressure loss. Moreover, the rib arrangements, rib configuration, and rib roughness parameters exhibit a relatively significant effect on the performance of the corrugated channels. On the
