源项不准确加载对源项法模型仿真精度的影响

针对平板多孔气膜冷却结构开展了真实模型和源项法模型数值仿真,在同实验数据对比取得较高精度的基础上探究了源项不准确加载对源项法模型仿真精度的影响,分析了加载方式、流量系数、网格参数等影响因素。结果表明:源项法模型可以代替建立带气膜孔真实模型对气膜冷却结构进行数值计算。网格准确定位的源项加载方式在粗细网格条件下均能取得较高的精度,点源项加载方式对网格较为敏感。因流量系数公式不准确导致的流量计算误差会影响源项法模型的计算精度,低吹风比下影响更为显著。气膜孔进出口处网格面密度应不少于4个/mm2,第一层网格高度的选取应符合所选用的湍流模型,以保证较高的计算精度。     

Experiments on film cooling with sonic injection into a supersonic flow

Film cooling experiments with sonic injection were conducted to investigate the effects of the number of the injection holes, the mass flow ratio, and the hole spacing on the film cooling effectiveness. The mainstream was obtained by the hydrogen-oxygen combustion, entering the experimental section at a Mach number of 2.0. The nitrogen with ambient temperature was injected into the experimental section at a sonic speed. The measured mainstream recovery temperature was approximately 910K. The mass flow ratio was regulated by varying the nitrogen injection pressure. The experimental results show that for the investigated cooling surface, the cooling effectiveness increases with the increase in the number of the injection holes with other parameters held constant. For a fixed cooling configuration, the cooling effectiveness increases with the increase in the mass flow ratio. Different from the subsonic film cooling, the optimal mass flow ratio is not observed. When the hole spacing is less than 4, no obvious difference is observed on the cooling effectiveness and lateral uniformity. With the mass flow ratio increasing further, this difference becomes much smaller. The shock wave also has an effect on the cooling effectiveness. Downstream the incident point of the shock wave, the cooling effectiveness is lower than that in the case without the shock wave.     

Evaluation of simulation-based training for aircraft carrier marshalling with learning cubic and Kirkpatrick’s models

Simulation-based training is a promising way to train a carrier flight deck crew because of the complex and dangerous working environment. Quantitative evaluation of simulation-based training quality is vital to make simulation-based training practical for aircraft carrier marshalling.This paper develops a personal computer-based aircraft carrier marshalling simulation system and a cave automatic virtual environment(CAVE)-based immersive environment. In order to compare the training effectiveness of simulation-based training and paper-based training, a learning cubic model is proposed and a contrast experiment is carried out as well. The experimental data is analyzed based on a simplified Kirkpatrick’s model. The results show that simulation-based training is better than paper-based training by 26.80% after three rounds of testing, which prove the effectiveness of simulation-based aircraft carrier marshalling training.     

基于分层体系的现代作战飞机方案评估

针对目前作战飞机方案评估中体系与方法的不足,依据飞机发展的时序性和评估内容的细化程度,确定了现代作战飞机方案评估的5个层次,它们分别为综合作战能力层、综合作战效能层、综合使用效能层、综合使用效费层和方案评价决策层.在分析各评估层特性的基础上,建立了各评估层的细化指标体系,改进和完善了各评估层的理论模型和计算方法,通过现...     

Aircraft vulnerability modeling and computation methods based on product structure and CATIA

Survivability strengthening/vulnerability reduction designs have become one of the most important design disciplines of military aircraft now. Due to progressiveness and complexity of modern combat aircraft, the existing vulnerability modeling and computation methods cannot meet the current engineering application requirements. Therefore, a vulnerability modeling and computation method based on product structure and CATIA is proposed in sufficient consideration of the design characteristics of modern combat aircraft. This method directly constructs the aircraft vulnerability model by CATIA or the digital model database, and manages all the product components of the vulnerability model via aircraft product structure. Using CAA second development, the detailed operations and computation methods of vulnerability analysis are integrated into CATIA software environment. Comprehensive assessment data and visual kill probability Iso-contours can also be presented, which meet the vulnerability analysis requirements of modern combat aircraft effectively. The intact vulnerability model of one hypothetical aircraft is constructed, and the effects of redundant technology to the aircraft vulnerability are assessed, which validate the engineering practicality of the method.     

涡轮径向轮缘密封非定常燃气入侵和封严效率的数值研究

为防止燃气入侵涡轮盘腔,提高运行安全性,对盘腔和轮缘密封间隙内非定常流动机理进行了深入研究。采用数值求解三维URANS（Unsteady Reynolds Averaged Navier-Stokes）和SST湍流模型的方法,研究了涡轮径向轮缘密封的非定常燃气入侵和封严效率。数值计算的径向轮缘密封的封严效率和环量比与实验数据吻合一致,验证了数值方法的可靠性。分析了6种冷气流量下径向轮缘密封的非定常压力分布、封严效率和燃气入侵与冷气出流特性。研究表明：冷气流量的增加阻止了径向轮缘密封处的燃气入侵和强化了冷气出流,径向轮缘密封盘腔内的封严效率随着冷气流量的增加而增加;动盘附近的封严效率高于静盘;入侵燃气基本被限制在径向轮缘密封的间隙区域。径向轮缘密封间隙出口处的主流周向时均压力随着冷气流量的增加而增加,周向时均压力最大值与最小值的差值随着冷气流量的增加而减小。当动叶前缘与静叶尾缘距离较近且不断靠近的过程,主流周向压力最大值与最小值的差值增大,动静叶相分离的过程周向压力最大值和最小值的差值减小。在静叶和动叶间非定常干涉作用下,轮缘密封间隙出口区域主流周向压力最大值与最小值差值较大时刻的主流低压区域具有优良的封严效率,同时高压区域的燃气入侵导致封严效率降低。     

基于 ABMS的无人机编队协同制空任务效能评估

无人机是海空作战的重要力量,制空作战是未来无人机的重要任务之一。为研究无人机编队协同制空作战的制胜机理,评估无人机编队协同制空作战效能:首先,对无人机编队协同制空任务进行分析,明确典型作战过程;然后,采用基于 Agent的建模与仿真(Agent-basedmodelingandsimulation,ABMS)方法,构建攻击型无人机、预警型无人机和空空导弹的 Agent模型,开展多无人机协同制空作战仿真和效能分析。结果表明,无人机探测距离、编队内攻击型无人机的数量,以及编队内有无预警型无人机,这些都将对作战效能产生重要影响,该结论可为无人机协同作战运用提供参考。     

RNP运行在蓉-拉航线上的优势研究

由于拉萨地区特殊的地理环境和恶劣的天气条件，大大增加了航空公司在成都一拉萨的运行难度。传统程序受地基导航设备的限制，而RNP程序基于星基导航源，不受地基导航设备限制，提高了运行的灵活性以及安全余度。RNP程序在蓉一拉航线的推广，降低了航线运行难度，保障了游客的出行，降低了运营成本，增加了经济效益，增加了航班时刻容量，提高了机场利用率，更好地保证飞行安全。     

空间信息网络对抗效能评估指标体系研究

定义了空间信息网络对抗综合效能评估概念，提出了建立空间信息网络对抗效能评估指标的原则和方法，给出了可信实用的评估指标体系，为空间信息网络对抗效能综合评估奠定基础。     

隐身技术对飞机作战效能影响研究

采用较完善的飞机，火控和武器系统模型以及详实的数据，应用分布式仿真原理的可视化仿真平台，进行了隐身飞机对实规第三代战斗机作战效能的仿真研究以及常规第三代战斗机采用隐身技术降低RCS指标后对作战效能的影响研究，仿真结果表明，未来的隐身飞机较常规第三代战斗机在 超视距作战中具有相当大的优势，第三代战斗机采用隐身技术降低RCS指标后可以提高其超视距作战能力。