The Design and build of a pulsejet UAV

The Design and build of a pulsejet UAV

Maziar Arjomandi

Ryan Mark M. Anderson, Nicholas Alexander A. Lukacs, Mitchell Leigh O'Callaghan, Karn Lee L. Schumacher, Michael Janis J. Sipols

and Terry John J. Walladge

(Commenced: 01-Jan-2008, Concluded: 30-Nov-2008 )

Maziar Arjomandi

Ryan Mark M. Anderson

Nicholas Alexander A. Lukacs

Mitchell Leigh O'Callaghan

Karn Lee L. Schumacher

Michael Janis J. Sipols

Terry John J. Walladge

The pulsejet powered Unmanned Aerial Vehicle (UAV) was designed and manufactured by a group of six undergraduate engineering students from the School of Mechanical Engineering at the University of Adelaide. The students, studying a mix of mechanical and aerospace engineering, aimed to design and build a UAV powered by a valveless pulsejet engine, which was also developed throughout the year. The use of pulsejets in aviation history has been almost non-existent since the end of World War II. However, interest in pulsejet technology has increased in recent years, as they offer a cheap and viable alternative from turbojet and ducted fan engines. The design of the aircraft was based around the pulsejet engine and is ultimately intended for use as a high speed target drone or decoy aircraft.

The development of the valveless pulsejet engines followed of from work completed by Coombes et al in 2007, with the aim to produce an engine and fuel system capable for use in flight. A wide range of development was undertaken on three different engines throughout the year, with over 100 static tests performed by the students. Significant improvements were achieved in the areas of engine thrust, thrust specific fuel consumption, engine weight and engine fuelling; most notably achieving successful operation using liquid fuels.

The allowance for pulsejet engine installation meant that a conventional airframe design was not suitable. A classical approach was taken to determine the performance and stability of the airframe. This design incorporated low swept wings, dual vertical stabilizers and an elevated swept tail, to produce an airframe that is capable of pulsejet powered flight. The airframe was manufactured by the students under the supervision and assistance of the Mechanical Engineering Workshop staff, and was constructed primarily from composite materials.

Successful flight of the aircraft was achieved on a ducted fan as it was seen as a more conventional power source, which has similar operational characteristics to the pulsejet engines. The flight tests showed that the airframe was stable, controllable and maneuverable. A cruise speed of 150km/hr was achieved during a four minute flight. The aircraft performed all handling requirements during the test flight.

The project goals set by the students at the beginning of the project reflected the ambitious nature of the project. The extension goals were particularly ambitious and related primarily towards the performance of the aircraft and engine. While some goals were not completely achieved, most were well within the performance capabilities of the aircraft.