Enhancing the Efficiency of the Turbogenerator Cooling System Through the Use of Finned Tubes in the Gas Cooler

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DOI https://doi.org/10.15407/pmach2025.03.034
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher Anatolii Pidhornyi Institute of Power Machines and Systems
of National Academy of Science of Ukraine
ISSN  2709-2984 (Print), 2709-2992 (Online)
Issue Vol. 28, no. 3, 2025 (September)
Pages 34-41
Cited by J. of Mech. Eng., 2025, vol. 28, no. 3, pp. 34-41

 

Author

Bohdan K. Shestak, National Aerospace University “Kharkiv Aviation Institute” (17, Vadyma Manka str., Kharkiv, 61070, Ukraine), e-mail: Bogdan.Shestak@gmail.com, ORCID: 0009-0002-0659-5394

 

Abstract

The reliability of a high-power turbogenerator largely depends on its cooling system. The trouble-free and efficient operation of this system, in particular the gas cooler, is a problem that has not been fully resolved as of now. A modernized design of a gas cooler for a 325 MW turbogenerator, featuring high-finned bimetallic tubes, is proposed in the paper. To substantiate the efficiency of such a design and determine the heat transfer reserve of the gas cooler, its thermal state was calculated. The obtained results showed that the water overheating in the gas cooler is 5 °C. At the same time, one section of the gas cooler provides heat loss removal of 1266 kW at a hydrogen flow rate of 6.66 m3/s and a cooling water flow rate of 200 m3/s, which meets the requirements for this gas cooler.

 

Keywords: turbogenerator, gas cooler, finned tubes, thermal calculation, criterion equations.

 

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Received 25 June 2025

Accepted 20 August 2025

Published 30 September 2025