Performance Charts for Multi-Pass Parallel Cross-Flow Heat Exchangers

Karthik Silaipillayarputhur and Tawfiq Al Mughanam
PO Box 380, Dept. of Mechanical Engineering, King Faisal University, Al Ahsaa, Saudi Arabia
Abstract — This study investigates the steady state sensible performance of multi pass parallel cross flow exchangers. Therein, the multi pass heat exchanger’s performance was expressed through performance charts. Performance charts describe the performance of the heat exchanger in terms of pertinent dimensionless parameters such as capacity rate ratio, number of transfer units (NTU) and heat exchanger effectiveness. Previously developed matrix approach was employed to study the performance at each pass of the parallel cross flow heat exchanger. A maximum of up to ten heat exchanger passes were considered in this work. Employing performance charts, the maximum NTU that would yield the maximum heat transfer (or the maximum heat exchanger performance) was determined. Increasing NTU beyond the maximum, shall not perhaps enhance the heat transfer considerably, and this violates the common perception that increasing NTU enhances the heat transfer. This aspect shall help the engineers in optimizing the heat exchanger in terms of size, weight, material, and cost. Likewise, if the heat exchanger was in a continuous operation, the performance charts can help to detect an underperforming equipment without conducting any detailed calculations.

Index Terms— performance charts, multi-pass parallel cross-flow heat exchanger, sensible performance of heat exchanger

Cite: Karthik Silaipillayarputhur and Tawfiq Al Mughanam, "Performance Charts for Multi-Pass Parallel Cross-Flow Heat Exchangers," International Journal of Mechanical Engineering and Robotics Research, Vol. 7, No. 5, pp. 478-482, September 2018. DOI: 10.18178/ijmerr.7.5.478-482
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