An improved energy management strategy for the solar powered unmanned aerial vehicle at the extreme condition

Solar powered unmanned aerial vehicle (UAV), achieving a long time flight, has been drawn attention. The energy management is a dominate role to determine the comprehensive performance of the solar powered UAV. In this work, a three dimensional numerical model is built to study the heat and mass transfer in the solar powered UAV at the extreme condition. The effects of flight velocity, flight attitude, day and light on the heat and mass transfer in the solar powered UAV are investigated in details. Then, an improved energy management strategy is proposed to improve the efficiency of the energy utilization for UAV. Results show that the temperature in the solar powered UAV is affected by the flight altitude. When the flight altitude varies from 11 km to 20 km, the temperature of the battery has approximately decreased by 5 K. The improved thermal management system can keep the battery temperature at about 220 K. The minimum temperature of the battery approximately increases by 50 K compared with the traditional structure. The heat transfer in the solar powered UAV is strengthened with the improved structure. Besides, the outer surfaces of the UAV are also influenced by the improved structure with the minimum temperature of the solar panel increased by 3 K. The data obtained from the analysis of the simulation results are helpful to the optimal design of global energy management.