Gas generating apparatus

Abstract

An improved gas generator apparatus having a compressor, a combustor, and a turbine having a turbine rotor coupled by a rotor shaft to the compressor rotor of the compressor. The combustor is spiral shaped and positioned between the compressor and turbine which allows the direction of flow of air or working gas to remain substantially unchanged from the compressor to the turbine, while maintaining a compact configuration. In operation, air drawn into the compressor is swirled circumferentially and pressurized by the compressor, and then delivered into a combustion chamber while it is being swirled. Air is expanded in the combustion chamber as it is swirled in and along the spirally shaped expansion chamber tube and then flows as a working gas into the turbine in which the gas drives the turbine rotor while the gas is still being swirled in the same direction. The air or working gas, therefore, maintains a swirling flow in one direction from the compressor to the turbine. In one embodiment, the scrolls for the compressor and turbine a compactly located in a normally empty space surrounding the shroud for the rotors of the compressor and turbine. In another embodiment, the separate compressor shroud is eliminated by providing a casing surrounding the spiral combustion expansion tube for receiving compressed air directly into that casing.