CERAMICS FOR THE ADVANCED AUTOMOTIVE GAS TURBINE ENGINE: A LOOK AT A SINGLE SHAFT DESIGN

The results of a preliminary analysis of a single shaft regenerative design with a single stage radial turbine are presented to show the fuel economy that can be achieved at high turbine inlet temperatures, with this particular advanced design, if the turbine tip speed and regenerator inlet temperature are not limited. The engine size was 100 hp for application to a 3500 lb auto. The fuel economy was analyzed by coupling the engine to the auto through a continuously variable speed-ratio transmission and operating the system at constant turbine inlet temperature over the Composite Driving Cycle. The fuel was gasoline and the analysis was for a 85 F day. With a turbine inlet temperature of 2500 F the fuel economy was 26.2 mpg, an improvement of 18 percent over that of 22.3 mpg with a turbine inlet temperature of 1900 F. The turbine tip speed needed for best economy with the 2500 F engine was 2530 ft/sec. The regenerator temperature was approximately 2200 F at idle. Disk stresses were estimated for one single stage radial turbine and two two-stage radial-axial turbines and compared with maximum allowable stress curves estimated for a current ceramic material. Results show a need for higher Weibull Modulus, higher strength ceramics.

• Supplemental Notes:
  • Conf-Presented at 5TH Army Materials Technol. Conf. Ceramics for High Performance Applications, 2, Newport, R. I., 21-25 Mar. 1977; Sponsored by Ammrc, Erda, and Darpa.
• Corporate Authors:

  Department of the Navy

  The Pentagon
  Washington, DC  United States  20350
• Authors:
  • Nosek, S M
• Publication Date: 1977

Media Info

• Pagination: 12 p.

Subject/Index Terms

• TRT Terms: Ceramic materials; Engines; Fuel consumption; Gas turbines; Gasoline; High temperature; Regenerators; Shafts (Machinery); Stresses; Temperature; Thermal stresses; Turbine engines; Vehicle design; Vehicle power plants
• Old TRIS Terms: Automobile engines; Engine design; Inlet flow; Tip speed
• Subject Areas: Design; Energy; Geotechnology; Highways; Materials; Vehicles and Equipment;

Filing Info

• Accession Number: 00166222
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: NASA-TM-X-73651, E-9163
• Files: TRIS
• Created Date: Sep 20 1978 12:00AM