Design, fabrication, and testing of a miniature impulse turbine driven by compressed gas

A miniature impulse turbine has been developed at the Rochester Institute of Technology. The goal of this project was to design, fabricate, and test a miniature turbine intended to power small vehicles such as micro air vehicles (MAVs). MAVs are vehicles with a maximum dimension of less then 15 cm and are used for surveillance and scouting. Due to the small size of MAVs, weight is a key design parameter. The batteries alone can account for more than 50% of the weight of the entire vehicle. A miniature turbine driven by compressed gas and coupled to a generator has been proposed as a replacement for batteries on these and other small vehicles. By decreasing the weight of the power systems, MAVs will be able to carry more instrumentation, fly longer, and be better able to complete their mission. To investigate the feasibility of this concept a turbine with a 6 mm impeller was designed, fabricated, and tested. The turbine produced 13.8 W of mechanical power. This corresponds to a power density of 230 W/N and a power to weight ratio of 44 W/kg. The generator attached to the turbine produced 208 mW of electrical power. The feasibility of a fuel tank, designed to hold compressed nitrogen at 69 MPa (10,000 psi), has also been investigated. The tank was designed to hold enough nitrogen to power a MAV for fifteen minutes. It was shown that the tank is feasible and could power a miniature turbine onboard a MAV