PARAMETER ANALYSIS ON CIRCULATION CONTROLLED CIRCULAR CYLINDER FOR NOTARTM TAIL BOOM

Lift on circulation control （CC） circular cylinder is calculated via numerical simulations based on 2D real- izable k-e epsilon viscous model and compared with experimental data. The simulation result shows an acceptable agreement with tested data. With the proved grid and simulation method, series of simulations are conducted to study the effect of parameters on lift. Single slotted tail booms under different clown wash velocities are optimized with the principle of generating maximum total moment around the main rotor shaft with same total power con- sumption. The results show that larger jet flow velocity, or smaller blow angle, or larger diameter of the cross section can help generating larger lift while enhancing the attachment of both the jet flow and down wash flow. Multiple slotted tail boom is better because it increases lift with same total slot width, and can increase lift by in- creasing total slot width without causing separation, also it helps generating high steady lift at a big rank of slot at- tack angles. To mount a guide vane （GV） at the exit of the slot, or shape the upper slot wall like a smooth-GV, or design the slot with an edge fillet is not recommended because it reduces the velocity of both the jet flow and the upstream of the attached downwash flow. Compared with other shapes of the slots, arcs-profiled slot performs better because of larger jet flow velocity and smaller blow angle. In order to generate the largest moment with same total power consumed by the entire NOTARTM system, total width of the slots and slot attack angle should be optimized according to velocity of down wash flow.     

艺无定法 融古铸今 现代工笔花鸟画画家罗仁琳

作者简介罗仁琳,1948年生于成都市,师承著名工笔画家王申勇,现为中国美术家协会会员,四川省美术家协会会员。作品《母子情》,参加《2004年全国中国画作品展》获优秀奖;     

涡轮试验台燃烧装置建模与仿真(Ⅱ)仿真结果与分析

为了实现计算机虚拟试验,在所建立基于混合物分数的分区模型和早期针对某涡轮试验台主体试验系统开展的三十八组件系统数值研究的基础上,结合调台试验开展了算法改进和仿真研究.对燃烧装置及影响燃烧过程元件仿真结果的分析表明,仿真全面揭示了空气流量主控调节阀、放气旁路调节阀、涡轮进口调节阀以及燃油流量对燃烧装置状态参数的动态影响过程,所获得的规律性结论为实际的调台试验提供了指导,显示了有限体积模型体系在管路系统仿真领域的工程应用价值和数值拓展潜力.     

航天器空间数据链路标准简析

空间数据链路协议是建立统一技术体制,促进航天机构合作,实现航天信息高效共享和充分利用的有效手段,因此研究并构建清晰合理的空间数据链路标准体系具有重大的现实意义。国外标准化组织构建了较为成熟的空间数据链路标准体系并编制了相关标准协议,文章介绍CCSDS （空间数据系统咨询委员会）、 ECSS （欧洲空间标准化合作组织）标准架构及标准内容,按照应用层、传输层、网络层、数据链路层、物理层的不同层次,简要介绍国外的空间数据链路协议标准,并对我国开展空间数据链路标准的研究提出相关建议。     

基于AK-IS法的航空齿轮泵滑动轴承可靠性分析

为研究高转速、低介质黏度运行的航空齿轮泵滑动轴承动压润滑可靠性，通过将Reylonds润滑方程与影响矩阵耦合，建立了考虑轴瓦弹性变形的航空齿轮泵滑动轴承弹流润滑(EHL)模型。考虑滑动轴承尺寸公差和运行工况等引起的不确定性，将与滑动轴承润滑特性密切相关的动压润滑的压力峰值作为可靠性判据，采用自适应Kriging和重要抽样法相结合的AK-IS法对滑动轴承动压润滑特性进行了可靠性及灵敏度计算。研究结果表明:考虑轴瓦弹性变形的压力峰值比刚性轴瓦压力峰值降低15.04%，表明滑动轴承弹流润滑对轴承动压润滑的影响不能忽略；基于AK-IS法的航空齿轮泵滑动轴承动压润滑可靠性分析具有准确性和高效性；各不确定因素对动压润滑可靠性的影响程度不同，其中轴承的半径间隙对可靠性最敏感，转速对可靠性最不敏感。