Direct Numerical Simulations of High-Pressure Turbine Stages with Endwalls

Project Description

Gas turbines are—and will continue to be—the backbone of aircraft propulsion, power generation, and mechanical drive due to their power density (i.e., thrust per unit engine weight), efficiency, and ability to adjust to rapidly varying loads. In the US alone, the natural gas and oil burn summed up to 27 × 1012 cubic feet and 6.3 × 109 barrels of oil equivalent respectively in 2015. Therefore, even at the current fuel price, a small engine performance improvement does have a fuel-spend advantage of the billion-dollar order, together with a significant CO2 emission benefit.
The Melbourne/GE team is exploiting the capability of the very efficient computational fluid dynamics code, the High-Performance Solver for Turbulence and Aeroacoustic Research (HiPSTAR) developed by Sandberg’s research group, to perform the first-of-a-kind direct numerical simulation of high-pressure turbine stages with realistic geometry and at engine-relevant conditions.
The generated data will shed light on the detailed fundamental flow physics—in particular the behavior of transitional and turbulent boundary layers affected by large-scale violent freestream turbulence—under strong pressure gradient and curvature. It will also help evaluate and develop lower-order models readily applicable to gas turbine designs. With the results, it will be possible to identify opportunities to increase turbine aerothermal efficiency by 2–4 percent and extend hot-gas-path durability. This would translate into combined cycle efficiency gains of 0.4–0.8 percent and thus have a significant economic and environmental impact.