Calculations of Economy of 18-Cylinder Radial Aircraft Engine with Exhaust-Gas Turbine Geared to the Crankshaft
Abstract
Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work. The calculations indicated that, for turbine and auxiliary supercharger efficiencies of 85 percent, minimum net brake specific fuel consumptions of 0.357 pound per brake horsepower hour at an altitude of 10,000 feet and of 0.323 pound per brake horsepower-hour at 30,000 feet can be obtained by gearing the exhaust-gas turbine to the engine crankshaft and operating the engine at a speed of 2000 rpm, an inlet-manifold pressure of 40 inches of mercury absolute, and a fuel-air ratio of 0.063. The reduction in net brake specific fuel consumption that can be obtained if the exhaust-gas turbine supplies all the auxiliary supercharger power and if its residual power is transmitted through gears to the engine crankshift, as compared with auxiliary turbosupercharging, is approximately 14 percent at an altitude of 10,000 feet and 21 percent at 30,000 feet.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1945
- Accession Number
- ADA312329
Entities
People
- Richard H. Zimmerman
- Richard W. Hannum
Organizations
- Glenn Research Center