Irreversibility Analysis and Numerical Simulation in a Finned-Tube Heat Exchanger Equipped with Block Shape Vortex Generator
Subject Areas : Mechanical EngineeringM. Ghazikhani 1 , E. Noorifar 2 , A. Mohammadian 3
1 - Department of mechanical Engineering,
Ferdowsi University of Mashhad, Iran
2 - Department of mechanical Engineering,
Ferdowsi University of Mashhad, Iran
3 - Department of mechanical Engineering,
Ferdowsi University of Mashhad, Iran
Keywords: Vortex generator, Steady Flow Rate, irreversibility, Heat Exchanger,
Abstract :
In this paper the effect of block shape Vortex Generators (VGs) on an air-water fin-tube heat exchanger has been studied experimentally using exergy analysis method. Also the effect of these VGs on increasing heat transfer rate has been simulated numerically and the Results show a good agreement with the experiments. In this research we used a wind tunnel to produce wind flow over heat exchanger in the range of 0.054 kg/s to 0.069 kg/s. Hot water was circulating with the steady volume flow rate of 240 L/h and the temperature of 44 to 68 centigrade in the system. These experiments have been repeated with and without VGs on the heat exchanger. Results show using the VGs has reduced Air Side Irreversibility to Heat transfer Ratio (ASIHR). To reveal the effect of VGs on heat exchanger performance with respect to reducing ASIHR, a quantity is used namely Performance of Vortex Generator (PVG). The results represent that PVG values are in the range of less than 15% to over 35% which represents the good effects of VGs on the heat exchanger performance.
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