Single Rotor Turbine Expander

Two forms of turbine expander are proposed. One, the single-rotor, partial admission, multistage, reentry type reaction turbine, is suitable for use at any realizable pressure ratio and should be especially effective in low mass flow engines because rotor blade Reynolds number can be maximized for a given flow area. The other, a modified form of the radial flow turbine, is adaptable to and abets structural compactness in both conventional gas turbine engines and systems based upon high pressure ratio wave engines. Both expanders inherently increase the maximum allowable material-limited gas inlet temperature because of the temperature averaging effect of the gas streams. The unsteady gas dynamics involved in the reentry type reaction turbine requires the modificationn and upgrading of existing computer simulation programs in order to address some of the unique characteristics of this machine and provide data for the design of a laboratory test rig. However, current capabilities in numerical techniques and modern computers permit effective solution of these problems. The performance and basic structural analysis of the radial flow turbine variant can be carried out with existing programs. These two expanders can drastically broaden the range of gas turbine propulsion applications.