Heat Transfer Enhancement in Air Cooled Gas Turbine Blade Using

Abstract

In this paper, an investigation of using corrugated passages instead of circular crosssection passages was achieved in conditions simulate the case in the gas turbine blade coolingusing ANSYS Fluent version (14.5) with Boundary conditions: inlet coolant air temperature of300 K with different air flow Reynolds numbers (191000, 286000 and 382000). Thesurrounding constant hot air temperatures was (1700 K). The numerical simulations was done bysolving the governing equations (Continuity, Reynolds Averaging Navier-stokes and Energyequation) using (k-ε) model in three dimensions by using the FLUENT version (14.5). Thepresent case was simulated by using corrugated passage of 3 m long, internal diameter of 0.3 m,0.01 m groove height and wall thickness of 0.01 m, was compared with circular cross sectionpipe for the same length, diameter and thickness. The temperature, velocity distributioncontours, cooling air temperature distribution, the inner wall surface temperature, and thermalperformance factor at the two passages centerline are presented in this paper. The coolant airtemperature at the corrugated passage centerline was higher than that for circular one by(12.3%), the temperature distribution for the inner wall surface for the corrugated passage islower than circular one by (4.88 %). The coolant air flow velocity seems to be accelerated anddecelerated through the corrugated passage, so it was shown that the thermal performance factoralong the corrugated passage is larger than 1, this is due to the fact that the corrugated wallscreate turbulent conditions and increasing thermal surface area, and thus increasing heat transfercoefficient than the circular case.