TURBOMECHANICAL TRANSMISSION FEASIBILITY STUDY.

Abstract : The purpose of the report was to describe the steady-state and dynamic performance of a novel gas-turbine-powered tank transmission. With this transmission variable-speed regenerative steering and propulsion are achieved over a wide torque-speed range by controlling the flow of hot gas from a single gas generator to four variable-nozzle-area reversible turbines. These turbines, one steering and three propulsion, transmit power at various gear ratios through a differential gear train, without the use of complex gear-changing mechanisms such as clutches or hydrostatic systems. The low specific weight (1.18 lb per hp), high efficiency (average 89 percent from 5 to 45 mph in forward operation) and lively performance (0 to 30 mph in 6.8 seconds with 100 lb per ton rolling resistance) of this system, as demonstrated by a preliminary mechanical design, digital-computer analysis of turbine performance, and analog-computer investigation of controlled transmission transient performance, compare very favorably with competing mechanical, hydraulic, and electrical transmission systems. It was therefore recommended that a development program be started immediately to prove the potential of this transmission. (Author)