Multi-objective optimum design for double baffle heat exchangers

•The heat transfer rate and pressure drop of passing airflow in a double baffle channel have been optimized generic algorithm.•The image processing method was used to detect baffles edges and generate mesh through this channel.•The turbulent flow field has been solved via Low Reynolds Chien’s model. The enhancement of the heat transfer rate of heat exchangers with a lower-pressure drop in passing fluid flow always was a consideration and challenging purpose for researchers. Increasing industrial equipment efficiency is a crucial problem for engineers. A multi-objective optimal design in order to increase heat transfer rate and low-pressure drop in a two-dimensional baffle heat exchanger considering turbulent fluid flow in a channel is presented. The genetic algorithm is utilized for obtaining an optimum arrangement of two flat-plate for satisfying mentioned purposes. The image processing method is used for detecting the edges of the mounted baffles and the appropriate mesh configuration is generated for the solution domain. Turbulent fluid flow and energy equations are discretized and solved over the physical domain by the finite volume method. The combination of genetic algorithm and image processing method with computational fluid dynamics provides an accurate new approach for optimization targets that is investigated in the present study. All generated baffles dimensions by the genetic algorithm are evaluated to achieve the design with an optimum value of a liner scaled function of two target parameters (i.e. temperature and pressure variations of the passing fluid flow through the channel). Investigating the results of all the generated and evaluated designs obtains the Pareto’s front in addition to the optimum design for these target parameters. For a case study with the same importance for the pressure drop (in Pa) and the passing fluid temperature increment (in K), the optimum baffles arrangement, with two 2 cm height baffles with 22 cm distance, shows a suitable heat transfer rate (ΔT = 32.04 K) and a low-pressure drop (ΔP = 3.007 kPa) for the passing fluid flow. All the possible optimum designs for this double baffles heat exchanger, with different importance of ΔT and ΔP, are obtained using the Pareto method.