摘要
为优化设计森林防火小型无人机的机身,降低机身质量,减少空气阻力,以双尾撑固定翼无人机为基础,利用Solid Works建立机身模型进行结构设计,并利用ANSYS-FLUENT对机身进行数值模拟。采用ANSYS ICEM CFD网格生成器生成PRISM网格结构进行网格划分,对机身进行气动分析。通过FLUENT仿真对设计进行改进,分析改进前后的流体场、阻力和质量差异。结果表明:可以采用ANSYS-FLUENT软件对森林防火小型无人机机身进行气动外形优化。机身的气动外形优化对减少阻力有明显的影响,改进后机身所受空气阻力减少了45.9%,机身质量减轻了27.8%。
Based on the double tail fin and fixed wing UAV,the structure model of the fuselage was designed by using the Solid Works. In order to optimize the design of small UAV fuselage and reduce the body mass and air resistance for better application in the forest fire prevention,we used ANSYS-FLUENT to simulate the fuselage. The grid structure was generated by ICEM CFD ANSYS mesh generator to generate the PRISM mesh. The fuselage aerodynamic analysis was carried out. By FLUENT software simulation,we improved the design,and analyzed the difference of the fluid field,resistance and weight before and after improvement. Results showed that the optimization of fuselage aerodynamic shape had significant effect in reducing drag. The air resistance of improved fuselage was decreased by 45. 9%,and the fuselage quality was reduced by 27. 8%. Our research adds a new chapter in the field of fuselage optimization,and provides guidance for aerodynamic optimization.
引文
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