Enhanced Performance Prediction of Hydrogen Fuel Cell Powered eVTOL UAV

View Video Presentation: https://doi.org/10.2514/6.2022-3382.vid The purpose of this paper is to increase the accuracy of eVTOL UAV performance prediction at steady-level-flight conditions. eVTOL UAV is powered by hydrogen fuel cell and battery. Inhouse program ADSP, which is capable of analyzing and optimizing fuel powered aircraft such as VLA, UAV, and UCAV is used as a baseline analysis program. Since ADPS can only perform for fuel powered aircraft, ADSP is upgraded for the battery and hydrogen fuel cell powered eVTOL UAV. However, applied methods in the ADSP are based on statical equations and numerical methods, as a result, the performance cannot be accurately predicted. Therefore, surrogate models for each discipline are developed by collecting high-fidelity data including experimental data and CFD results, and according to the analysis code framework. The aerodynamics analysis fidelity is improved by CFD data, propulsion analysis fidelity is increased by conducting experimental data, in addition, the hydrogen fuel cell experimental data are also used to correct the efficiency to predict the fuel consumption. The high accuracy performance is predicted by integrating the fidelity enhanced model of each discipline, physically. This paper shows an effective integration method for predicting the enhanced performance of eVTOL UAVs in a practical approach. Not only the performance of different flight modes but also the whole flight mission can be predicted. Inhouse program ADSP analysis is used as a baseline, and improved fidelity analysis is used as enhanced analysis, which is compared for performance and mission analysis. The analysis results show that the enhanced analysis prediction results of drag, power, and energy required at forwarding flight are almost 2 times higher than the baseline analysis resulting in lower maximum endurance and lower maximum range which is more realistic to actual flight.