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In the present study, the effect of high temperature radiant heaters’ arrangement on providing appropriate and uniform thermal conditions under asymmetric flow field have been investigated in an industrial environment. For this reason, a sample industrial environment with one inlet and outlet opening has been considered with two different types of high temperature radiant heaters’ arrangement: single radiant heater and couple radiant heaters. For the mentioned conditions, continuity equation, momentum equations, energy equation and radiative transfer equations have been solved by OpenFoam numerical solver. Also energy consumption has been evaluated in the present study. The results show that in presence of asymmetric flow field, using couple high temperature radiant heaters in comparison with single radiant heater causes more uniform temperature distribution and decrease about 10 degrees of Celsius in maximum temperature of floor. Also, this can cause to decrease about 35 percent in floor temperature distribution deviation from the average appropriate temperature (27 degrees of Celsius). Moreover, the results indicate that utilizing couple high temperature radiant heaters leads to increase in energy consumption about 10 percent in comparison with single radiant heater.

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Gravitational search algorithm (for the first time) has been used for two-objective optimization of airfoil shape, in this article. 2D compressible Navier-Stokes equations with Spalart-Allmaras model has been used to simulate viscous and turbulent flow. First, efficiency and accuracy of the optimizer sets have been evaluated using inverse optimization. Objective functions were differences between drag and lift with their corresponding values of the NACA0012 objective airfoil, as a set of airfoils randomly were chosen as starter airfoils, in this case and the aim was to obtain the airfoils that satisfy the considered objective functions. In direct optimization, gravitational search algorithm that has been used in the present work, has achieved proper parameters (related to the Parsec method) and consequently has found optimized airfoils with maximum lift and minimum drag objective functions. This algorithm starts to slove using a set of airfoils and it is directed towards the airfoils that provide the mentioned objective functions. Comparison of the results (Pareto fronts) shows better and more proper performance of the gravitational search algorithm rather than particle swarm optimization algorithm and former researches (done using other meta-heuristic algorithms) for aerodynamic optimizations.