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Giel, Paul

Publications and source records attributed to Giel, Paul.

Heat Transfer Measurements on the Endwall of a Variable Speed Power Turbine Blade Cascade

Heat transfer measurements were obtained on the endwall of a 2-D section of a variable speed power turbine (VSPT) rotor blade linear cascade. Infrared thermography was used to help determine the transition of flow from laminar to turbulent as well as determine regions of flow separation. Steady state data was obtained for six incidence angles ranging from +15.8 deg to -51 deg, and at five flow conditions for each angle. Nusselt number was used as a method to visualize flow transition and separation on the endwall surface and showed the effects of secondary flows on the surface. Nusselt correlation with Reynolds number from multiple flow conditions was used to plot local values of the correlation exponent and indicated the state of the local boundary layer as the flow transitioned from laminar to turbulent as well as secondary flow features.

variable speed power turbine↗

Inlet Turbulence and Length Scale Measurements in a Large Scale Transonic Turbine Cascade

Constant temperature hotwire anemometry data were acquired to determine the inlet turbulence conditions of a transonic turbine blade linear cascade. Flow conditions and angles were investigated that corresponded to the take-off and cruise conditions of the Variable Speed Power Turbine (VSPT) project and to an Energy Efficient Engine (EEE) scaled rotor blade tip section. Mean and turbulent flowfield measurements including intensity, length scale, turbulence decay, and power spectra were determined for high and low turbulence intensity flows at various Reynolds numbers and spanwise locations. The experimental data will be useful for establishing the inlet boundary conditions needed to validate turbulence models in CFD codes.

hotwire↗

Dual-Spool Turbine Facility Design Overview

The next generation of aircraft engines, both commercial and military, will attempt to capitalize on the benefits of close-coupled, vaneless, counter-rotating turbine systems. Experience has shown that significant risks and challenges are present with close-coupled systems in terms of efficiency and durability. The UEET program needs to demonstrate aerodynamic loading and efficiency goals for close-coupled, reduced-stage HP/LP turbine systems as a Level 1 Milestone for FY05. No research facility exists in the U.S. to provide risk reduction for successful development of close-coupled, high and low pressure turbine systems for the next generations of engines. To meet these objectives, the design, construction, and integrated systems testing of a Dual-Spool Turbine Facility (DSTF) facility has been initiated at the NASA Glenn Research Center. The facility will be a warm (-IOOO'F), continuous flow facility for overall aerodynamic performance and detailed flow field measurement acquisition. The facility will have state-of-the-art instrumentation to capture flow physics details. Accurate and reliable speed control will be achieved by utilizing the existing Variable Frequency Drive System. Utilization of this and other existing GRC centralized utilities will reduce the overall construction costs. The design allows for future installation of a turbine inlet combustor profile simulator. This presentation details the objectives of the facility and the concepts used in specifying its capabilities. Some preliminary design results will be presented along with a discussion of plans and schedules.

Giel, Paul↗