Experimental exergy and entransy analyses on designed and fabricated crossflow heat exchanger

Abstract

A crossflow heat exchanger (CFHEx) is designed and fabricated in a workshop. For designing this heat exchanger (HEx), the number of passes, frontal areas, HEx volumes, heat transfer areas, free‐flow areas, ratios of minimum free‐flow area to frontal area, densities, mass flow rates of flowing fluids, maximum/minimum heat capacities, heat capacity ratio, outlet temperatures of hot/cold fluids, average temperatures, mass velocities, Reynolds numbers, and convective heat transfer coefficients are evaluated by considering Colburn/friction factors. After fabrication of the HEx, effectiveness, exergy destruction, entransy dissipation, entransy dissipation‐based thermal resistance, entransy dissipation number, and entransy effectiveness for hot/cold fluids sides are found at different flow rates and inlet temperatures of fluids. By experimental results, optimum operating conditions are found, which gives maximum effectiveness and entransy effectiveness but minimum rates of exergy destruction, entransy dissipation, entransy dissipation‐based thermal resistance, and entransy dissipation number for the fabricated CFHEx. This study is concluded as follows: minimum exergy destruction and entransy dissipation rates (ie, 3.061 kJ/s·K and 1125.44 kJ·K/s, respectively) are found during experiment 2. Maximum entransy effectiveness of hot/cold fluids (ie, 0.689/0.21) is achieved in experiment 1. Moderate values of entransy dissipation number (ie, 4.689), entransy dissipation‐based thermal resistance (ie, 0.04 s·K/J), exergy destruction (ie, 3.845 kJ/s·K), and entransy dissipation (ie, 1374.04 kJ·K/s) rates are found during experiment 1. Maximum effectiveness (ie, 0.4) for the fabricated HEx is also obtained through experiment 1. After comparative analyses, it is found that experiment 1 provides optimum results, which shows the best performance of the fabricated HEx.

Performance of Pure Crossflow Heat Exchanger in Sensible Heat Transfer Application

“…A generalized Nusselt number correlation was also developed in the research work. Geete et al [8] fabricated a cross flow heat exchanger in a workshop and experimentally analyzed effectiveness, exergy, and entransy. Narkhede and Sur [9] considered the performance of a hollow compact micro-lattice-based cross flow heat exchanger.…”

Energy and exergy analyses of fabricated solar drying system with smooth and rough surfaces at different conditions: A case study

“…Youcef‐Ali et al 27 determined the average coefficient of internal moisture transfer for the drying of potato slices. Exergy analyses have been done on different solar systems: parabolic solar collector, compound parabolic solar collector, evacuated tube, single‐ and double‐solar still by researchers 28–34 . Mugi and Chandramohan 35 calculated the rates of inlet/outlet exergy, exergy losses, and exergy efficiencies of indirect solar dryer systems at free and forced convection techniques with 3.69 and 5.1 sustainability indexes, respectively.…”