The conceptual design and optimization of a tilt-rotor Micro Air Vehicle(MAV) for a well-defined mission are performed. The objective of this design cycle is to decrease the design time in order to efficiently create ...The conceptual design and optimization of a tilt-rotor Micro Air Vehicle(MAV) for a well-defined mission are performed. The objective of this design cycle is to decrease the design time in order to efficiently create a functional tilt-rotor drone. A flight mission is firstly defined for a tiltrotor MAV performing hovering and cruise flight scenarios. Secondly, a complex wing shape is chosen and modeled in order to determine the final shape. The initial shape is scaled in order to acquire an arbitrary wingspan of one meter. For the specific area and wingspan, the aspect ratio of the designed wing shape is found to be equal to 2.32. Thirdly, a constraint analysis of the MAV is performed by using an energy balance analysis for six different flight scenarios. This analysis yields the required power loading and wing loading. Fourthly, the weight of the vehicle is estimated using both statistical and computational methods. After estimating the total weight and the wing loading of the MAV, the surface of the wing is determined, yielding a final wingspan of 0.76 m. Subsequently, considering the total weight of the designed MAV, the needed lift coefficient is determined.Fifthly, using the lift coefficient in conjunction with XLFR5, a batch of airfoils is selected and analyzed to evaluate the aerodynamic coefficients of the wing with each airfoil. This analysis ultimately leads to the optimum airfoil being selected. Finally, design of the fuselage and tail, internal components selection, and servo-mechanisms design are carried out prior to a stability analysis. All these proposed steps are needed to design efficient and functional tilt-rotor MAVs.展开更多
以投资费用最小和系统可用输电能力(available transfer capability,ATC)最大为目标,建立了多类型柔性交流输电系统(flexible AC transmission system,FACTS)的多目标优化模型,并考虑了多个约束条件。提出一种嵌套的多目标粒子群优化算...以投资费用最小和系统可用输电能力(available transfer capability,ATC)最大为目标,建立了多类型柔性交流输电系统(flexible AC transmission system,FACTS)的多目标优化模型,并考虑了多个约束条件。提出一种嵌套的多目标粒子群优化算法求解该多约束非线性N-P困难问题的Pareto解集,该算法的外层用于计算多目标优化问题,内层用于计算系统的可用输电能力和静态电压稳定指标。结果表明不考虑其他因素时,晶闸管控制串联电容器(thyristor controlled series capacitor,TCSC)是最合理的配置选择;当FACTS安装数量有限时,相比统一潮流控制器(unified power flow controller,UPFC)和静止同步补偿器(static synchronous compensator,STATCOM),多种FACTS设备混合安装可以在经济上和效果上取得较好的平衡;若电网在有限投资水平下需要较高的可用输电裕量,应首先考虑并联型和串联型FACTS混合安装的方案。在IEEE-14节点中对所提方法进行的验证表明该方法的正确性和有效性,该方法可以同时确定FACTS的安装类型、安装地点和补偿容量。展开更多
基金the financial support from New Mexico Space Grant Consortium
文摘The conceptual design and optimization of a tilt-rotor Micro Air Vehicle(MAV) for a well-defined mission are performed. The objective of this design cycle is to decrease the design time in order to efficiently create a functional tilt-rotor drone. A flight mission is firstly defined for a tiltrotor MAV performing hovering and cruise flight scenarios. Secondly, a complex wing shape is chosen and modeled in order to determine the final shape. The initial shape is scaled in order to acquire an arbitrary wingspan of one meter. For the specific area and wingspan, the aspect ratio of the designed wing shape is found to be equal to 2.32. Thirdly, a constraint analysis of the MAV is performed by using an energy balance analysis for six different flight scenarios. This analysis yields the required power loading and wing loading. Fourthly, the weight of the vehicle is estimated using both statistical and computational methods. After estimating the total weight and the wing loading of the MAV, the surface of the wing is determined, yielding a final wingspan of 0.76 m. Subsequently, considering the total weight of the designed MAV, the needed lift coefficient is determined.Fifthly, using the lift coefficient in conjunction with XLFR5, a batch of airfoils is selected and analyzed to evaluate the aerodynamic coefficients of the wing with each airfoil. This analysis ultimately leads to the optimum airfoil being selected. Finally, design of the fuselage and tail, internal components selection, and servo-mechanisms design are carried out prior to a stability analysis. All these proposed steps are needed to design efficient and functional tilt-rotor MAVs.
文摘以投资费用最小和系统可用输电能力(available transfer capability,ATC)最大为目标,建立了多类型柔性交流输电系统(flexible AC transmission system,FACTS)的多目标优化模型,并考虑了多个约束条件。提出一种嵌套的多目标粒子群优化算法求解该多约束非线性N-P困难问题的Pareto解集,该算法的外层用于计算多目标优化问题,内层用于计算系统的可用输电能力和静态电压稳定指标。结果表明不考虑其他因素时,晶闸管控制串联电容器(thyristor controlled series capacitor,TCSC)是最合理的配置选择;当FACTS安装数量有限时,相比统一潮流控制器(unified power flow controller,UPFC)和静止同步补偿器(static synchronous compensator,STATCOM),多种FACTS设备混合安装可以在经济上和效果上取得较好的平衡;若电网在有限投资水平下需要较高的可用输电裕量,应首先考虑并联型和串联型FACTS混合安装的方案。在IEEE-14节点中对所提方法进行的验证表明该方法的正确性和有效性,该方法可以同时确定FACTS的安装类型、安装地点和补偿容量。
