Computational fluid dynamics (CFD) based propeller design improvement for high altitude long endurance (HALE) UAV

PurposeHigh Altitude Long Endurance Unmanned Aerial Vehicle (HALE UAV) driven by a hybrid power between battery and solar panel have attracted many researchers. The HALE UAV which develops at Bandung Institute of Technology has design requirements of a 63 kg MTOW with a cruise velocity of 22.1 m/s at an altitude of 60,000 ft propelled by two propellers. The main problems that arise with the propellers gained from the market are these propellers cannot operate properly at the cruise phase due to inadequate thrust and high drag value. This paper aims to design a propeller that solves those problems.Design/methodology/approachThe Larrabee method is used to design this propeller geometry with an output in the form of a chord and twist distribution. The CFD approach method is used to improve the design resulting from the Larrabee method.FindingsThis study shows that the inputted thrust value of the propeller designed using the Larrabee method is always higher than the thrust value resulting from the CFD simulation with a difference of around 20% so a design improvement process using CFD is required.Originality/valueThe analysis of propeller implementation in various mission profiles shows that this propeller can operate fully from climbing at sea level to cruising flight at an altitude of 60,000 ft. The same procedure can be applied in other HALE UAV cases to generate a propeller design with different objectives.