UAV Power Plant Performance Evaluation

Abstract

UAV's are proven to be cost effective when compared to manned aircraft and minimize the risk related to a pilot's life. The primary focus of my research was on identifying and evaluating state of the art propulsion technologies for Tiger-Shark class UAV. This would help us in identify areas of future improvement in Power, Weight & Efficiency. For this purpose, a detailed survey of all the propulsion technologies in the 5-100HP range was conducted and a dynamometer was built to perform a firsthand comparison and evaluation of engine performance. Based on the survey, it was observed that 2-stroke engines are superior in terms of their high energy density P/W ratio. Since, the survey results were based on manufacturer data which were obtained using different methods and under varying test conditions, it is highly mandatory to validate these data to support any conclusion obtained from it. The dynamometer that we built is capable of testing any IC engine in the range of 5-30 HP. With the limited time frame available, two engines were chosen for the preliminary test runs on the dynamometer namely, "BME 150 LT", "BME 116 Xtreme"- two-stroke carburetor engine. Later on, the BME116 engine was retro-fitted with EFI system and results from all three engine configurations were compared. There is not a significant difference observed between the EFI & Carburetor type of BME116, the BME 116 EFI is more suitable for the target UAV class power range. Future work include, testing of wide range of engines, with & without EFI.