Optimizing Internal Cooling in Gas Turbine Blades Using 45° Rib Turbulators
Authors: Ahmed M. Bagabir
DOI: 10.87349/ahuri/181021
Page No: 1-21
Abstract
This study employs computational methods to investigate the influence of 45° angled rib turbulators on flow dynamics and heat transfer. The analysis encompasses both stationary and rotating square channels. The primary objective is to evaluate how this rib configuration impacts thermal performance and fluid behavior, particularly in the context of gas turbine blade cooling applications. A Computational Fluid Dynamics (CFD) approach employs k-ε turbulence models to accurately simulate flow patterns and thermal distributions. Simulations are conducted for Reynolds numbers ranging from 20,000 to 40,000 and rotation numbers between 0.0 and 0.4. Key findings indicate that the employed ribs enhance heat transfer by disrupting boundary layers, increasing turbulence and mixing. Peak heat transfer occurred downstream of each rib due to flow separation and reattachment; consequently, the ribbed configuration provided up to three times greater heat transfer compared to a smooth channel. The study quantifies the trade-off between enhanced convective heat transfer and the associated pressure drop, emphasizing the interaction between rib-induced turbulence and Coriolis forces. Results indicate a decrease in the thermal enhancement factor (TEF) with increasing Reynolds number for 45° ribs, suggesting that frictional losses at higher flow rates may outweigh heat transfer gains. Under rotating conditions, the study characterizes the asymmetry in heat transfer between the leading and trailing walls, underscoring the role of rib orientation in blade cooling effectiveness. This research offers valuable insights for optimizing cooling systems in engineering applications, particularly in the design of channels that improve thermal management through strategic integration of rib turbulators.
