Thermal-hydraulic optimization of plate heat exchanger: A multi-objective approach

In the present work, thermal-hydraulic optimization of plate heat exchanger is investigated. Maximization of overall heat transfer coefficient and minimization of total pressure drop considered simultaneously as objective functions during multi-objective optimization. Multi-objective heat transfer search algorithm is applied to obtain a set of Pareto-optimal points for conflicting objectives. An application example of plate heat exchanger is presented to identify conflicting thermal-hydraulic behaviour. Eight geometric design variables which include port diameter, a horizontal distance of ports, a vertical distance of ports, length of compact plates, plate thickness, chevron angle, enlargement factor and number of plates are investigated for optimization. Decision-making method is adopted to select the final optimal solution from Pareto points. Distribution of each design variables corresponding to Pareto optimal points is presented to identify its effect on conflict behaviour of the thermal-hydraulic function. The sensitivity of design variables to the optimized value of the thermal-hydraulic function is also presented and discussed. Finally, the validation of the present work is carried out by experimentation on plate heat exchanger. The comparative results revels that 8.87% deviation in overall heat transfer coefficient and 9.96% deviation in total pressure drop are observed between optimization and experimental results.