Improving thermal performance of turbine blade with combination of circular and oblong fins in a wedge channel: a numerical investigation

Goveraiahgari Venkatesh; Reddygari Meenakshi Reddy; Pabbisetty Mallikarjuna Rao

doi:10.1515/tjj-2024-0010

Article

Improving thermal performance of turbine blade with combination of circular and oblong fins in a wedge channel: a numerical investigation

Goveraiahgari Venkatesh , Reddygari Meenakshi Reddy and Pabbisetty Mallikarjuna Rao

Published/Copyright: March 6, 2024

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From the journal International Journal of Turbo & Jet-Engines Volume 41 Issue 4

Abstract

Because of its narrow and aerodynamic design, cooling the trailing edge of a turbine blade offers an essential problem. For the trailing edge internal cooling of gas turbine blades, wedge-shaped channels are used. Pin-fin arrays play a critical role in enhancing heat transmission at the trailing edge of turbine blades. The flow and heat transfer properties of a number of wedge channels with staggered pin-fins of varied shapes are used to develop a design with a more effective heat transfer effect and reduced flow resistance. The present study compares the combination of circular pin fins and oblong pin fins in a wedge duct with a Reynolds number range of 12,000–85,000 and a constant heat flux (surface) of 3280 W/m² applied to the bottom wall, top wall, and surfaces of the fins. The results indicate that the pressure loss is less in circular fins at the centre and oblong fins side by side, and it is 23.67 % less than circular and oblong fins in opposite positions. The Heat transfer coefficient for circular and oblong fins in opposite positions is 16.72 % higher than circular fins at centre and oblong fin side by side. The thermal performance factor is almost the same for both cases.

Keywords: oblong pin fin; circular pin fin; friction factor; wedge duct; thermal performance factor

Corresponding author: Goveraiahgari Venkatesh, Research Scholar, Jawaharlal Nehru Technological University Anantapur, Ananthapuramu, AP, India; and Department of Mechanical Engineering, G Pulla Reddy Engineering College, Kurnool, Affiliated to Jawaharlal Nehru Technological University Anantapur, Ananthapuramu, AP, India, E-mail: venkatesh.mech5118@gmail.com

Research ethics: Not applicable.
Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: The authors state no conflict of interest.
Research funding: None declared.
Data availability: Not applicable.

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Received: 2024-01-20

Accepted: 2024-02-14

Published Online: 2024-03-06

Published in Print: 2024-12-17

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https://doi.org/10.1515/tjj-2024-0010

Keywords for this article

oblong pin fin; circular pin fin; friction factor; wedge duct; thermal performance factor