Evaluating the effects of bifurcation angle on the performance of a novel heat exchanger based on contractual theory

Abstract

In this study, numerical and experimental analysis is presented to study the influences of bifurcation angles on the thermo-hydraulic performance in a novel heat exchanger by adopting contractual theory. The parameters of overall heat transfer coefficient, exergy efficiency, pressure drop, and coefficient of performance are investigated with three bifurcation angles (α = 120o, 150o, 180o). The mass flow rate in shell side is constant at 0.33 kg/s whereas the mass flow rates in tubes fluctuate from 0.169 to 0.331 kg/s. The numerical model was accomplished and the numerical results were validated by the experimental results and the error percentages are agreeable. The results show that the novel configurations of the heat exchanger based on constructed theory enhance heat transfer compared to standard shapes. The bifurcation angle of 150o accomplishes the highest enhancement of heat transfer whereas the heat exchanger with a bifurcation angle of 180o has the highest pressure drop. The configuration with α = 150o achieves higher values of COP compared to the other angles. The exergy efficiency improves with Re where the configuration with α = 180o has higher exergy efficiency. The contours, streamlines, and vectors of the temperature, velocity, and pressure distributions give investigation for the fluid stream inside the shell and tubes.