Effect of Helix Angle and Cross Section of Helicoidal Ducts in Gas Turbine Blade Cooling

Abstract

Gas turbines play a prominent role in aircraft propulsion and land-based power generation systems. To improve the turbine blade efficiency and power, present-day gas turbines are subjected to higher inlet temperatures. However, this has an adverse effect as it increases the thermal loads on gas turbine blades which weaken the structure. Modern gas turbines are operated at temperatures beyond 1500°C. Therefore, power output from a gas turbine blade is directly dependent on the cooling, so that turbine blades are not damaged from such high thermal loads. In this paper, an effort has been made to numerically analyze the effect of helix angle on circular helicoidal shape geometry in gas turbine blade cooling. Different cross-section of helicoidal geometries discussed in this paper is elliptical, circular, square and triangular. It is observed that reduction in helix angle results in improved cooling of a gas turbine blade. It is also inferred that elliptical helicoidal ducts enhance cooling as compared to other helicoidal geometries due to a larger convective area and higher heat dissipation as compared to other cross-section of helicoidal ducts. Copyright © 2019 Praise Worthy Prize S.r.l. - All rights reserved.