Modified through-flow wave-rotor cycle with combustor-bypass ducts

A wave rotor cycle is described that avoids the inherent problem of combust or exhaust gas recirculation (EGR) found in four port, through-flow (uniflo w) pressure-gain wave rotor cycles currently under consideration for top pi ng gas-turbine engines. The recirculated hot gas is eliminated by the judic ious placement of a bypass duct that transfers gas from one end of the roto r to the other, The resulting cycle, when analyzed numerically, yields a me an absolute temperature for the rotor that is 18% below the already impress ive value (approximately the turbine inlet temperature) predicted for the c onventional four-port cycle. The absolute temperature of the gas leading to the combustor is also reduced from the conventional design by 17%. The ove rall design-point pressure ratio of this new bypass cycle is approximately the same as the conventional cycle. This paper will describe the EGR proble m and the bypass-cycle solution, including relevant wave diagrams. Performa nce estimates of design and off-design operation of a specific wave rotor w ill be presented, The results were obtained using a one-dimensional numeric al simulation and design code.