The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight conditions.The study is intended to support the design and developm...The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight conditions.The study is intended to support the design and development of aerospace vehicles where stability analysis,performance optimization,and aircraft design are of primary importance.The following parameters are considered:Mach numbers(M)of 1.3,1.8,2.3,2.8,3.3,and 3.8,angle of incidence(θ)in the range from 5°to 25°,pivot position from h=0.2 to 1.The results of the CFD numerical simulations match available analytical data,thereby providing evidence for the reliability of the used approach.The findings provide valuable insights into the relationship between the surface pressure distribution,the Mach number and the angle of incidence.展开更多
When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necess...When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function.展开更多
对大规模交直流网络下的高压直流控制保护系统进行参数优化设计,是保证灵活交流输电系统暂态性和稳定性良好的重要手段。目前由于实时仿真技术的网络节点受限、费用高等缺点,使其不适合此规模网络的试验和设计任务。文中基于ABB公司高...对大规模交直流网络下的高压直流控制保护系统进行参数优化设计,是保证灵活交流输电系统暂态性和稳定性良好的重要手段。目前由于实时仿真技术的网络节点受限、费用高等缺点,使其不适合此规模网络的试验和设计任务。文中基于ABB公司高压直流控制保护系统硬件结构特点和MACH2(modular advanced control for HVDC and SVC)系统运作机理,提出了等价实时离线仿真的实现原理和方法,使离线仿真达到实时仿真的效果;通过与实际工控机运行结果进行比对,验证了其有效性;同时对工程用高压直流控制中的电流控制功能进行了等价实时仿真。仿真结果分析表明,基于所提出的等价实时仿真原理和方法,利用商业通用的离线仿真软件,可高效地进行高压直流控制保护系统优化设计。展开更多
文摘The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight conditions.The study is intended to support the design and development of aerospace vehicles where stability analysis,performance optimization,and aircraft design are of primary importance.The following parameters are considered:Mach numbers(M)of 1.3,1.8,2.3,2.8,3.3,and 3.8,angle of incidence(θ)in the range from 5°to 25°,pivot position from h=0.2 to 1.The results of the CFD numerical simulations match available analytical data,thereby providing evidence for the reliability of the used approach.The findings provide valuable insights into the relationship between the surface pressure distribution,the Mach number and the angle of incidence.
基金supported by the Structures and Materials(S&M)Research Lab of Prince Sultan Universitysupport of Prince Sultan University in paying the article processing charges(APC)for this publication.
文摘When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function.
文摘对大规模交直流网络下的高压直流控制保护系统进行参数优化设计,是保证灵活交流输电系统暂态性和稳定性良好的重要手段。目前由于实时仿真技术的网络节点受限、费用高等缺点,使其不适合此规模网络的试验和设计任务。文中基于ABB公司高压直流控制保护系统硬件结构特点和MACH2(modular advanced control for HVDC and SVC)系统运作机理,提出了等价实时离线仿真的实现原理和方法,使离线仿真达到实时仿真的效果;通过与实际工控机运行结果进行比对,验证了其有效性;同时对工程用高压直流控制中的电流控制功能进行了等价实时仿真。仿真结果分析表明,基于所提出的等价实时仿真原理和方法,利用商业通用的离线仿真软件,可高效地进行高压直流控制保护系统优化设计。
