Document Type : Research Article
Mechanical Engineering, Amirkabir university of Technology, Tehran, Iran
In this article, modeling and multi-objective optimization of laminar fluid flow in flat tubes equipped with different porous layers is performed using CFD techniques, ANFIS, GMDH type ANN and NSGA II. The design variables are two geometrical parameters of tubes, tube flattening (H) and porous layer thickness ratio (HP), Porosity ( ), Entrance flow rate (Q) and Wall heat flux ( . The objectives are to maximize the convection heat transfer coefficient (h) and minimizing the pressure drop. At first, the problem is solved numerically in various flat tubes using CFD techniques and two objective parameters in tubes are calculated. Numerical data of the previous step will be applied to model h and using ANFIS and Grouped Method of Data Handling (GMDH). In the next step, Pareto based multi-objective optimization will be carry out by the use of GMDH model and NSGA II algorithm. The results showed that the ANFIS model yields better prediction in comparison with other methods and the obtained Pareto solution contains significant design information on flow parameters in flat tubes partially with porous insert. The results show that the best configuration for the maximum heat transfer and the minimum pressure loss is H=4mm and Hp= 0.75.