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691.
冯晨 《海军航空工程学院学报》2015,30(2):134-138
根据机载设备人机交互需求,设计了机载大屏幕显示器的红外触摸组件。采用了双向红外收发、动态地址扫描、环境光强扫描、多点触摸扫描等技术,组件具有高分辨率、高精度、高可靠性、抗强光直射干扰、支持多点触控等特点。测试结果表明,该组件性能指标完全满足机载大屏幕显示器的人机交互需求。 相似文献
692.
《中国航空学报》2020,33(1):88-101
Introducing flexibility into the design of a vertically flapping wing is an effective way to enhance its aerodynamic performance. As less previous studies on the aerodynamics of vertically flapping flexible wings focused on the lift generated in a wide range of angle of attack·a 2D numerical simulation of a purely plunging flexible airfoil is employed using a loose fluid–structure interaction method. The aerodynamics of a fully flexible airfoil are firstly studied with the flexibility and angle of attack. To verify whether an airfoil could get aerodynamic benefit from the change in structure, partially flexible airfoil with rigid leading edge and flexible trailing edge were further considered. Results show that flexibility could always reduce airfoil drag while lift and lift efficiency both peak at moderate flexibility. When freestream velocity is constant, lift is maximized at a high angle of attack about 40° while this optimal angle of attack reduces to 15° in drag-balanced status. The airfoil drag reduction, lift augmentation as well as efficiency enhancement mainly attribute to the passive pitching other than the camber deformation. Partially deformed airfoil with the longest length of moderate flexible trailing edge can achieve the highest lift. This study may provide some guidance in the wing design of Micro Air Vehicle (MAV). 相似文献
693.
倾转旋翼飞行器旋翼对机翼向下载荷计算模型 总被引:3,自引:2,他引:1
针对倾转旋翼飞行器悬停和小速度前飞的直升机飞行模式下旋翼下洗流对机翼的气动干扰影响,建立了一个机翼向下载荷的计算模型.该模型中,最关键的是建立旋翼对机翼的气动干扰面积模型.此模型考虑了倾转旋翼飞行器几何尺寸条件、发动机短舱倾转角和飞行状态等参数.最后将此模型集成到XV-15倾转旋翼飞行器飞行动力学模型中,进行配平计算,... 相似文献
694.
过渡区侧向喷流干扰的并行DSMC数值模拟研究 总被引:2,自引:0,他引:2
在高空低密度环境,空间飞行器的控制面效率下降较快,反作用控制系统(RCS)作为改变飞行姿态或轨道的直接力系得到大量应用,为了精确预测高空RCS喷流与稀薄大气的干扰效应,本文建立了直角与表面非结构网格混合结构的DSMC数值算法以及网格自适应算法,保证了碰撞分子是在自适应后的亚网格内选取,提高了计算精度.采用静态随机负载平衡技术构建了并行DSMC代码,计算分析了不同压比条件下的三维平板模型侧向喷流与稀薄大气的干扰流场.计算的复杂流场结构和表面流动特征、分离长度与低密度风洞试验有较好的一致性.在保持来流参数不变的情况下,喷流干扰区的分离长度及喷流透射高度随着喷流压比的增大而增大.随着来流稀薄度的增加,来流对喷流的影响越来越弱,而喷流自身的影响区域却越来越大. 相似文献
695.
The interaction of the solar wind with the Martian exosphere and ionosphere leads to significant loss of atmosphere from the
planet. Spacecraft data confirm that this is the case. However, the issue is how much is actually lost. Given that spacecraft
coverage is sparse, simulation is one of the few ways for these estimates to be made. In this paper the evolution of our attempts
to place bounds on this loss rate will be addressed. Using a hybrid particle code the loss rate with respect to solar EUV
flux is addressed as well as a variety of numerical and chemical issues. The progress made has been of an evolutionary nature,
with one approach tried and tested followed by another as the simulations are improved and better estimates are produced.
The results to be reported suggest that the ion loss rates are high enough to explain the loss of water from Mars during earlier
solar epochs. 相似文献
696.
Sketching is traditionally associated withdoodling simple strokes on a piece of paper.Only few professionals outside of design andthe fine arts have recognized the expressivepower of this intuitive modality. However,sketching seems particularly well suited tocapture objects and situations in a spatialenvironment, such as geographic space. To learnmore about the techniques and strategies peopleuse when sketching, a survey of sketching wasconducted. The study showed that paper andpencil sketches contain mostly simple andabstract objects that are composed of only fewstrokes. The spatial configuration of a sceneis primarily expressed through the topologicalordering of objects relative to each other.Metric relationships are used to refine spatialconfigurations. These and other findingssuggest that sketching is an appropriatemodality to interact with a computer where onewants to describe and capture objectconfigurations in a spatial environment, suchas a geographic information system (GIS). 相似文献
697.
The aerodynamic interaction effect of rotorwake on fuselage isan importantproblem in designof helicopter. It affects flight performance,equi-librium,control stabilization and vibrational level.The developing trend of modern helicopter is thatthe size is towards more compact and the load ofrotor disk is towards heavier. The load of rotordisk is about 2 0 kg/ m2 in the 5 0 s,but for modernhelicopter it is up to about 5 0 kg/ m2 . Therefore,the strong rotor wake impacting the closerfuselageand t… 相似文献
698.
人机交互风格及其发展趋势 总被引:12,自引:0,他引:12
人机交互的风格经历了命令界面、图形界面、多媒体界面等主要发展阶段,目前正向虚拟现实技术和多通道用户界面的方向发展。本文简要回顾人机交互技术的历史,并进而探讨什么是理想、自然的人机交互模式。 相似文献
699.
为了明晰S弯喷管的流固耦合特性,数值模拟了流固耦合作用下双S弯收敛喷管的结构变形特征及其内/外流特性。结果表明:S弯喷管的圆转方弯曲构型产生了非均匀的流场分布,并增强了结构的弹性特征,它们通过交换气动载荷与变形位移数据形成了S弯喷管流固耦合的作用机理。在气动载荷作用下,S弯喷管沿Y向的最大变形位移为25.3mm,它位于喷管出口上壁面的中心位置。当喷管的结构变形稳定时,第二弯转弯处下壁面的气流加速至局部超音速,壁面静压大幅降低;第一弯下游上壁面附近形成了气流分离区;喷管出口喷流沿轴向向上偏转。流固耦合作用导致S弯喷管的流量系数减小0.6%,推力系数降低1.8%。矩形截面与弯曲构型是影响S弯喷管流固耦合特性的主要几何特征,其中矩形截面能够显著增大喷管的变形位移;S形弯曲构型虽然能够有效抑制变形特征,但它导致喷管多个区域出现变形,喷管的结构变形分布变得更加复杂。 相似文献
700.