Asian Journal of Engineering and Applied Technology (AJEAT)
Thermodynamic Analysis of Efficiency- NTU Parameters for Parallel Flow Type Heat Exchanger under the Effect of External Heat LeakAuthor : Roopesh Tiwari and Govind Maheshwari
Volume 7 No.1 January-June 2018 pp 59-65
The work presented here analyses theoretically a parallel flow type heat exchanger which is subjected to external heat leak, from the cold fluid side or from the hot fluid side. Efficiency-NTU relations are developed and the results obtained are presented graphically, reflecting the effect of heat capacity ratios and the heat leak on the efficiency of the heat exchanger. The graphs follow the similar pattern with increasing heat capacity ratios. Also, as the heat leak is increased, the graphs show opposite behavior when the minimum heat capacity is on the hot side to that when the minimum capacity is on the cold side. The derived expressions are reduced to the classical effectiveness-efficiency-NTU relations for the parallel flow type heat exchangers as the heat leak approaches zero.
Heat exchanger, Effectiveness, Efficiency, Heat leak, Heat capacity ratio
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