Design, Manufacturing, and Testing of a Small Through Flow Wave for Use Within the Brayton Cycle
With the ever growing popularity of drones and other unmanned aerial vehicles for military, commercial, and private usage, there is a desire to improve performance in terms of range, altitude, and flight speed. Current technology uses either electric motors or internal combustion engines: both piston and jet engine types. These sorts of engines undergo significant e ciency degradation as their size decreases. While some e ciency may be recovered via intensive design studies, the cycles are approaching the limit to their operating physics. A possible solution to this is to change the operating physics to something more immune to scaling losses; a pressure exchange device known as a wave rotor is one option. A wave rotor operates via oscillating pressure waves in order to compress the gas as opposed to the mechanical compression utilized by conventional engines. This thesis outlines the design, manufacture, and component testing of a wave rotor within the Brayton cycle. While the focus of this research was the wave rotor, included in the design and testing were the many support components necessary to drive the cycle, notably a small can type combustor. Using a NASA developed quasi one dimensional CFD code, the wave rotor cycle was designed to power a kilowatt sized Class 2 UAVs. After the CFD modeling, hardware design and manufacture began on the various components. After manufacture, the various components were tested including the venturis, the combustor, and the wave rotor itself. The component testing showed great promise for the full rig testing. Hardware build up and the test plan is ongoing but expected to show e ciency gains when compared to similar sized combustion engines. Improved e ciency gains will significantly decrease the operating costs of small drones while improving range and altitude performance to all operators.