Session: 04-26 Combustion - Modeling IV

Submission Number: 178806

CFD-Based Parametric Design Optimization of a Fuel-Flexible Jet-Stabilized Combustor for Marine Gas Turbines 

The transition of maritime transport toward low-emission, carbon-neutral operation requires fuel-flexible gas turbines capable of utilizing hydrogen and other alternative clean fuels. Within this context, the MARPOWER project is developing an intercooled recuperative gas-turbine system for shipboard energy conversion, and this paper presents a CFD analysis of its jet-stabilized, two-stage combustor. The study aims to obtain an optimized combustor design by assessing the influence of key geometric parameters on flow recirculation, flame stabilization, and emissions under elevated pressure and temperature conditions representative of marine operation. A parametric design study was carried out, systematically varying nozzle pitch radius, premixing length, number of nozzles, and air-split ratios to identify configurations that enhance combustor performance. To ensure the reliability of the results while maintaining low computational cost, the CFD framework was verified through mesh-independence and feasibility studies. The results identified nozzle pitch radius as a dominant parameter governing flame stability, whereas variations in premixing length provided only limited improvements due to the inherent nozzle geometry and operating principle. Reducing the pitch radius effectively mitigated flame–wall interactions and quenching, thereby lowering thermal stresses. Moreover, adjusting the pilot-air fraction promoted richer operation and stronger recirculation, enhancing main-stage stabilization and enabling flexible-fuel operation. The optimized configuration demonstrated stable combustion, low emissions, and a total pressure loss of approximately 6% across the combustor, ensuring high cycle efficiency and confirming the scalability of the jet-stabilized, two-stage combustion concept.

Presenting Author: Nikhil Shinde German Aerospace Center, Institute of Combustion Technology

Presenting Author Biography: Nikhil Shinde is a Research Associate at the DLR, where his work involves the application of CFD to design fuel flexible, low-emission gas turbine combustors. His research background is centered on numerical modeling, including a Master's thesis at DLR on validating simulations for hydrogen combustion and a specialization project on the aerothermal analysis of steam turbine seals. He received his M.S. in Computational Engineering from Technische Universität Braunschweig and B.E. in Mechanical Engineering from the University of Mumbai.

Authors:

Nikhil Shinde German Aerospace Center, Institute of Combustion Technology
Timo Lingstädt German Aerospace Center, Institute of Combustion Technology
Sebastian Bellaire German Aerospace Center, Institute of Combustion Technology
Andreas Huber German Aerospace Center, Institute of Combustion Technology