STTR Phase I: Wave Rotor Constant-Volume Combustion for Energy Efficiency and Greenhouse Gas Abatement in Gas Turbine Engines

The broader impact/commercial potential of this Small Business Technology Transfer Phase I project will likely be the dramatic improvement in the energy efficiency of power plants, aircraft and other vehicles, through the development of a novel pressure gain combustor for gas turbine engines. Today, these engines consume about a third of all natural gas and generate one fifth of the electricity in the US. The novel wave-rotor combustor being developed in this project will likely enable reduction of fuel consumption, carbon emission and weight of gas turbines dramatically, each by a factor of 18-20% along with lowering other emissions. Further, this research project will potentially lead to new combustion engines for lighter and more efficient road vehicles, engines for distributed generation, hybrid vehicles and robotic aircraft, larger engines for utility power generation, aviation and ships. The objectives of this Phase I research project are to apply research on jet ignition phenomena and pulsatile flow to create the novel wave-rotor-constant-volume combustor for gas turbines. Ignition of a combustible mixture by transient high speed jets of hot reactive gas allows fast repeating combustion. Pulsatile flow results in efficient and compact gas compression and expansion processes. The new combustor circumvents the weight, vibration, noise and maintenance requirements of piston crank engines and the pressure and temperature limits of gas turbines. The concept combines multiple innovations. First, constant volume combustion creates a fundamentally more efficient thermodynamic cycle relative to current Brayton cycle gas turbine and the Otto/Diesel cycle positive displacement engines. Second pulsatile flow and pressure waves are used to further improve thermodynamics and reduce engine size and weight. Third, accelerated combustion is achieved through controlled jets of reactive gas and shock flame interaction. The research thus enables a transformative combustion process and a superior class of combustion engines, while retaining proven compact turbomachinery components.