Rotordynamic Scaling of Kilowatt-Class Turbomachines
Advisor: Dr. Choon Tan
We are researching small gas turbine engines for remote power generation applications. Fuel-based energy systems can provide a much higher energy density than battery-electric systems, making them ideal candidates for portable power systems, such as unmanned aerial vehicles and autonomous robots. Traditionally, applications in the kilowatt scale would be filled by reciprocating piston engines. Here, we study the potential use of gas turbine engines in the kilowatt scale. Gas turbines have the potential for higher power density, superior mechanical reliability, and greater fuel flexibility when compared to piston engines. The primary challenges are ensuring stable operation and acceptable efficiency.
We are characterizing the scaling relationships between the system-level gas turbine design parameters, such as pressure ratio, turbine inlet temperature, and power output, and the rotordynamic parameters, including critical speed and operating speed. These scaling parameters will lend a new perspective towards creating rotordynamically robust small gas turbine engines. The aim is to create generic design guidelines for the use of different bearing technologies, different shaft configurations, and to create appropriate material indices. We are working with Brayton Energy LLC and the Office of Naval Research to apply this research towards a small, lightweight, auxiliary turbogenerator for unmanned aerial vehicle applications.