In-depth analysis of flow field aerodynamic mechanism in integrated combustor–turbine structure for heavy-duty gas turbine

In future heavy-duty gas turbines, to achieve higher output power and efficiency, cutting aerodynamic losses and cooling air use is key. This paper puts forward a novel integrated combustor-turbine module (ICTM) for heavy-duty gas turbines, using an innovative integrated design approach to boost aerodynamic efficiency. The ICTM consolidates the combustor liner, transition duct, and first-stage nozzle guide vanes into a single module, utilizing low-solidity composite blade profiles. Three configurations (N18, N20, and N24) were developed and tested. Advanced diagnostic techniques, including pressure-sensitive paint, particle image velocimetry, and five-hole probe measurements, were employed to investigate the aerodynamic characteristics. Numerical simulations complemented the experimental study, providing detailed insights into the flow mechanisms. Results indicate that the ICTM demonstrates excellent aerodynamic performance with minimal secondary flows. The total pressure loss coefficient for the N20 configuration was 0.0486, representing a 31.3% improvement over traditional designs. This research offers a promising new direction for gas turbine performance optimization by enhancing fluid dynamics, implementing effective flow control strategies, and reducing total pressure loss.