The GT-225-An Engine for Passenger-Car Gas-Turbine Research

The intensive search for an alternative low-emission powerplant for passenger cars has led to a re-evaluation of the gas turbine for this type of service. The GT-225 engine was designed as a research tool to aid in making such an evaluation. Factors which received special consideration in making design decisions included exhaust emissions, fuel economy and drivability. An extensive combustor development effort was undertaken to achieve low emissions. The engine has been installed in a test-bed vehicle to permit evaluation of emissions and other factors under actual driving conditions.

Vehicle tests of the engine fitted with a low-emission combustor demonstrated the following emissions: 0.11 g/km (0.18 g/mile) HC; 1.2 g/km (2.0 g/mile) CO; and 0.23 g/km (0.38 g/mile) NO_x. In addition, fuel economy competitive with that of conventional passenger cars at turnpike speeds, substantially improved throttle response in comparison with earlier heavy-duty turbine engines and engine braking equal to that provided by the typical powertrain in today's cars were demonstrated. Continued effort is being directed toward improvements in components, controls and engine design in order to further the potential of the gas turbine as an alternative engine for passenger cars.