The stator and rotor blade hub sections designed for a high pressure turbine stage were studied in detail for their aerodynamic and heat transfer characteristics.The profile sections were tested in the National Aeronautical Laboratory(NAL) cascade tunnels over a range of exit flow Mach numbers.The flow field and heat transfer characteristics of the cascades were analysed,employing the Euler code,the method of singularities and the K- turbulence model.The results indicated that there was scope for improving the blade profile sections for the proposed high Mach number application.
In particular,it has been observed that the energy loss coefficients of the stator blade are rather high around the design point.The air swallowing capacity of the rotor blade design appears to be inadequate compared to the design expectations.The predictions of the surface pressure distributions obtained from the Euler code are generally in good agreement with the measured values in the Transonic Cascade Tunnel.The measured distribution of heat transfer coefficients around the blade surfaces give a useful data base for the design of the cooled blades.Prediction of the heat transfer for these transonic blades using the K- model of turbulence appears to be in general,not adequate.Recourse to correlation of the measured data using power-law relations appears to be promising ,at least as a short time measure
