Numerical Study of Brinkman Number Effects on Heated Viscoelastic Fluid Flow in Channel with Sudden Expansion

In this paper, the inertial and non-isothermal flow of viscoelastic fluid inside thesymmetric planar sudden expansion channel with an expansion ratio of 1:3 has been numericallyinvestigated in the range of Brinkman numbers (0.01≤Br≤20). The rheological and nonlinear model ofPhan Thien-Tanner (PTT) is used for modeling viscoelastic fluid behavior. The finite volume method(FVM) is employed to discretize the governing equations and the PISO algorithm is used to solve theseequations simultaneously. Due to the significant effect of temperature changes on the viscoelastic fluidproperties, these properties are considered as temperature-dependent and the viscous dissipations termis considered in the energy equation. The main purpose of this study is to investigate the effects ofBrinkman numbers on the heat generation by viscous dissipations term used in the energy equation.Therefore, the streamlines, the length of vortices, the isothermal lines, the distributions of velocity andtemperature and local Nusselt numbers have been examined in the channel expanded part. The resultsshow that for the hydrodynamic and thermally developing zone, the maximum value of the local Nusseltnumbers on the walls of the channel expanded part is located at the end of the first and second vortices.