Improving Turbine Efficiencies Through Heat Transfer and Aerodynamic Research in the Steady Thermal Aero Research Turbine (START)

The Pennsylvania State University (Penn State), in conjunction with its industry partner, Pratt & Whitney (P&W), will test new cooling improvements for the turbine rotating blade platform in order to increase machine efficiency and reduce costs which will be referred as the Proprietary Cooled Blade Studies. The scope of the project includes: (1) the planning and execution of the Steady Thermal Aero Research Turbine (START) facility and instrumentation upgrades to include a heated main gas path with full-span airfoils, long-wave infrared thermography, and unsteady pressures; (2) the design and manufacturing of a rainbow set of blades with baseline and advanced cooling configurations; (3) measurements of aerodynamics and heat transfer for baseline and advanced configurations over a range of cooling flows, Reynolds numbers, rotational Reynolds numbers, and flow angles; and (4) continual assessment of additive manufactured components to reduce costs and advance cooling designs. The project will focus on performing the first open-literature, consecutive comparisons of baseline and advanced cooling configurations in a test turbine with realistic engine hardware and flow conditions. The project will also allow direct comparisons of airfoil heat transfer measurements to be made in three relevant testing environments: low speed and temperature, high pressure temperature static conditions, and high velocity rotational conditions. This back-to-back comparison will provide data to guide the gas turbine industry in introducing these new cooling technologies into operating gas turbines. This work builds on previous NETL-Regional University Alliance (RUA) Contract FWP-2012.03.02. Since the inception of the Proprietary Cooled Blade study and the desire to involve a larger community of turbine manufacturers, DOE-NETL initiated an annual meeting at Penn State to gather industry feedback on the integration of the cooling technologies into the proprietary blade design. Companies attending the meeting represented all of the US turbine manufacturers as well as a number of other federal agencies such as NASA, ONR, and the AF. While the companies were pleased to provide input, they also realized that the data produced would be limited given the blade geometry was proprietary and only scaled results would be shared. During these meetings, there was a strong push from the manufacturers to develop a turbine geometry that all could have access to rather than have a proprietary blade design. This push started the inception of discussions of a common turbine geometry. Through further DOE-NETL and Penn State discussions with industry and other federal agencies, the National Experimental Turbine (NExT) Cooled Blade Studies was initiated. At the DOE Peer Review in April 2019, the reviewers emphasized the need for a common turbine geometry. NExT is proposed to be a turbine testing platform focused on US technology advancement, designed in collaboration with four turbine manufacturers –Honeywell, Pratt & Whitney, Solar, and Siemens – in partnership with Agilis, a turbine design firm. The NExT vane and blade geometry as well as all of the baseline data will be shared with all of the turbine manufacturers, US federal agencies and US universities within the data management plan. While all turbine geometries are highly proprietary, the goal for NeXT is to provide a modern turbine design that can be used by several organizations, which is a distinctly different effort than the proprietary cooled blade studies, which uses a proprietary blade design thereby limiting the applicability for the turbine manufacturers. The NExT platform is essential to provide all the details needed to do accurate code development.