The nozzle guide vane (NGV) is a critical component of a gas turbine system. Its function is to accelerate and guide/turn the flow coming from the combustor and direct it to the blade row as smoothly as possible (i.e. with minimal aerodynamic losses). Flow through the NGV is highly complex and includes a multitude of physical phenomenon including: transition, separation, compressibility, mixing, unsteadiness, and heat transfer. Nozzle guide vanes are stationary blade rows that are exposed to the hottest gas temperatures from the combustor, which requires that it be aggressive cooled. The coolant interacts with the main flow and induces further aerodynamic losses in the stage.
Hub Flow Interaction on Film Cooled Nozzle Guide Vane in Transonic Annular Cascade
This research attempts to answer the question: where does the hub coolant flow go in a real-world Siemens industrial gas turbine vane? Using CO2 as coolant and gas analysis we are able to measure concentrations of CO2 downstream of the vane and gain an understanding of where the coolant ends up. Does it stay near the endwall as intended or does it get carried away by the passage vortex leaving the endwall unprotected?
CFD Modeling of Heat Transfer on Surface of Uncooled/Cooled Nozzle Guide Vane
Numerical analysis was performed for the heat transfer over the surface of nozzle guide vane under the condition of reduced vane count using three dimensional computational fluid dynamics (CFD). Reducing vane count increases power to weight ratio but does the NGV remain effective in guiding the flow?
Effect of Coolant Injection Angle on Nozzle Endwall Film Cooling in Linear Cascade
Though the research is abundant on effect of injection angle on film cooling, there are few studies that look at the influence on real engine geometry particularly with a contoured endwall which heavily influences the path of not only the mainstream but the coolant. This work uses experimental and computational models to understand this effect.