Abstract

Mohamed Abd El Fatah Mohamed Teamah
evaluation of different turbulence modelsnumerical solvers for a transonic turbine blade cascade
the gas path over the turbine blades is a very complex flow field due to the variation of flow regimethe corresponding heat transfer, this investigation is devoted to study the twothree-dimensional predictive modeling capability for airfoil external heat transfer by using pressure based solver pbsdensity based solver dbs. the results show the effects of strong secondary vortexes , laminar-to-turbulent transition,also show stagnation region characteristics .rnsimulations were performed on an irregular quadratic grid with the fluent 6.3 software package which solves the rans equations by using finite volume methods with second order accuracy. data were obtained for the exit reynolds numbers equal the facility maximum point of 2.50×106, including the blade aspect ratio of 1.17. it has been concluded in particular that rather fine computational three dimensional grids are needed to get accurate local heat transfer controlled by complex 3d structure of secondary flows.rnresults of numerical simulation of the twothree-dimensional turbulent flow heat transfer in a transonic turbine cascade are presented. employing several turbulence models (spalart allmaras, rng k-Єsst k-ω model) .rndetailed heat transfer predictions are given for a power generation turbine rotor with 127 deg of nominal turningan axial chord of 130 mm with highly three-dimensional blade passage flows that resulted from the high flow turningflow boundary layer with highly three-dimensional blade passage flows that resulted from the high flow turningflow boundary layer. the comparison was made with theexperimentalthe numerical results of gielcolleagues [1]a good agreement was found with the density based solverspalart allmaras turbulent model .