Journal of Technology in Aerospace Engineering

Journal of Technology in Aerospace Engineering

Investigation of the Role of Convective Heat Transfer Coefficient Distribution in the Optimization ot Internal Cooling Passages of a Gas Turbine Blade

Document Type : Research Article

Authors
1 Department of Mechanical Engineering، Amirkabir university of Technology، Tehran، Iran
2 Department of Mechanical Enhineering,Amirkabir University of technology
3 Department of Mechanical Engineering، Faculty of Engineering، Arak University، Arak، Iran
10.22034/jtae.2026.10.3.1
Abstract
This study focuses on optimizing the internal cooling channel geometry of gas turbine blades to reduce their peak surface temperature. The paper is structured in two main parts: The first part examines the blade surface temperature distribution in different cooling channel configurations to evaluate the effect of the number and distribution of these holes on heat transfer, maximum surface temperature, and total mass flow rate a nd the second part, the external flow around the gas turbine blade has been carefully examined as a determining factor in the external convection heat transfer mechanism, so that changes in the flow regime from laminar to turbulent directly affect the surface heat exchange rate and consequently shape the temperature distribution and overall efficiency of the system. Through a series of simulations, we observed that increasing the number of cooling holes from one to ten led to a noticeable drop in maximum surface temperature, from 811.3 K down to 728.9 K. However, the rate of improvement diminished significantly beyond six holes. The six-hole configuration emerged as the most effective, offering a 65 K reduction compared to the baseline, along with improved thermal uniformity and balanced mass flow. Additionally, the external convective heat transfer coefficient showed pronounced peaks near the blade tip and in transitional flow regions. These findings guided the strategic placement of cooling holes to maximize thermal efficiency.
Keywords
Subjects

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Articles in Press, Accepted Manuscript
Available Online from 31 May 2026

  • Receive Date 18 February 2026
  • Revise Date 27 February 2026
  • Accept Date 12 May 2026
  • First Publish Date 31 May 2026