Numerical Simulation of Flow Field and Heat Transfer inside a New Enhanced Tube

Abstract:

A numerical simulation was carried out for the flow and heat transfer in the Double-Inclined Streamlined Ribs tube (DISR tube) which is used in the automobile exhaust heat recovery. This paper is aimed to find the optimum ribs parameters for best heat transfer perfomance. The solution was calculated by ANSYS/FLUENT and the SIMPLEC algorithm was used for the velocity-pressure coupling. The results shows that the optimal value of DISR tube is rib length (l=38mm), rib inclined degree (α=45o), rib height (h=2.5mm) and rib pitch (P=60mm). The heat transfer in the DISR tube is enhanced 72.6% on average compared with a plain tube and the friction factor increases 180.9% on average at Re=12000~50000. In the DISR tube, the field synergy angle reduce from 90° to 80° and the heat transfer is enhanced significantly. The paper shows that the field synergy angle declines greatly near every ribs, and this is the chief reason for the heat transfer enhancement.

• Periodical: Applied Mechanics and Materials (Volumes 513-517)
• Pages: 2629-2634
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.513-517.2629
• Online since: February 2014
• Authors: Cheng Long Xu*, Wei Jun Liu, Wei Ping Hu
• Keywords: Convective Heat Transfer Enhancement, Field Synergy, Numerical Simulation, Streamline-Shaped Ribs

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