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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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In this paper, the heat transfer of viscoelastic fluid flow have numerically simulated inside a symmetric planar channel with 1:3 abrupt expansion. For modeling the rheological and nonlinear behavior of inertial flow related to the viscoelastic fluid, exponential form of the Phan Thien-Tanner (EPTT) model has been used. The thermal boundary condition of constant temperature has been considered at the inlet and on the walls of channel. Also, velocity is uniform and constant at the inlet of channel and its value is determined by the Reynolds number of flow. Due to the significant effect of temperature on the viscoelastic fluid properties, viscosity, relaxation time, specific heat capacity and thermal conductivity have been taken as a function of temperature and dissipation term has been employed in the energy equation. For coupling the governing equations, the PISO algorithm is utilized and finite volume method (FVM) is employed for discretizing these equations. In this study, the effect of inertial force is investigated on the velocity distribution, temperature distribution and variation of local and average Nusselt numbers in the expanded part of channel. Despite the symmetry in the planar channel, increasing the Reynolds number forms the symmetric and asymmetric flows inside the expanded part of channel. For asymmetric flows, increase of Reynolds number from 40 to 100 (growth of 2.5 times the Reynolds number) resulted in a 1.7-fold increase for the maximum values of local Nusselt numbers in the vicinity of the upper and lower walls of the channel expanded part.