飞翼布局运输机气动设计方法研究

由于飞翼布局的运输机具有结构强度、气动效率、总体装载以及RCS隐身等方面的优良特性,它成为未来大型运输机的气动布局方案中最引人关注的一种布局形式.以0.85马赫为巡航设计点,设计了一架起飞总重在250吨左右,最大载重量在50吨,最大航程在8000公里以上的飞翼布局运输机.通过采用Euler方程数值解法进行气动特性评估,在初始设计方案的基础上进行进一步的改进设计,有效地提高了初始方案的升阻特性和力矩特性.最终设计结果表明提出的设计思路具有一定的可行性和适用性.     

Recent advances in film cooling enhancement: A review

Film cooling is an indispensable scheme in the design of highly-efficient cooling configurations to satisfy the thermal protection requirement of turbine hot section components. During the last few decades, vast efforts have been paid on the discrete-hole film cooling enhancement. In this paper, some of the recent literatures related to the passive strategies (such as shaped film cooling holes, upstream ramps, shallow trenches, mesh-fed slots) and the active strategies (such as the use of pulsation modulating device or plasma actuator) for film cooling enhancement are surveyed, with the aim at presenting an updated overview about the state of the art in advanced film cooling. In addition, some challenging issues are also outlined to motivate further investigations in such a broad topic.     

突出高职学生能力培养的语文教学改革研究

高职语文教学改革坚持“与专业相对接、以就业为导向、以能力为本位、以学生为中心、以教师为关键”等重要理念．是高职语文教学适应职业教育发展的需求，是高职语文教学服务于高职教育“高素质、高技术技能型”的总目标的重要体现，也是突出高职语文学生能力培养本位，摆脱高职语文被边缘化的基本途径。只有这样，才能真正发挥出高职语文学科的人文性和工具性特点。     

国际空间站有效载荷集成流程分析

国际空间站（ISS）针对有效载荷从论证、研制到随ISS飞行的过程建立了标准集成流程和精益集成流程两种模式,这两种模式互为补充,有效支持了ISS载荷随飞行任务的滚动实施。在有效载荷集成过程中,NASA采用多线并行的方式,其集成流程从理念上不完全等同于传统卫星有效载荷随飞行任务实施的研制流程,并设置有效载荷集成经理,架设有效载荷管理方、研制方和研究团队之间的桥梁。通过对国际空间站有效载荷集成过程的深入分析,提出可供我国空间站有效载荷集成借鉴的经验,如提供快速集成流程、加强有效载荷集成管理、强化有效载荷全寿命周期管理等。     

职业院校学生终身学习能力的培养策略研究

分析了终身学习的内涵与内容,提出培养职业院校学生终身学习能力的必要性,并提出了切实可行的提高职业院校学生终身学习能力的具体措施。     

基于蒙特卡洛仿真的平行双跑道容量评估方法

跑道容量评估是科学评价跑道规划方案、合理安排航班时刻、精准实施流量管理的重要基础性工作.针对平行双跑道容量评估问题,分析了跑道容量影响因素,考虑到跑道分配、机型分配、起降类型分配、进离港点分配、航班流队列顺序等随机性,采用蒙特卡洛方法模拟变量随机性,按照离散事件系统原理,递归计算每个航班的起降时刻,通过统计1h内的航班数量获得容量值.以西安机场双跑道为例,针对现行的相关进近、独立进近、隔离运行3种模式,分别计算了跑道容量值.仿真计算结果显示,相关进近模式容量60架次/h,独立进近模式跑道容量为78架次/h,隔离运行模式跑道容量为52架次/h,平均每次仿真时间仅为1 min,说明方法效率较高.与2015年高峰61架次/h相比仅相差1个架次,计算结果说明方法是有效的.     

基于受油能力的加油机效能分析

受油能力逐渐成为加油机设计的必备能力。然而现有的加油机效能分析方法没有考虑受油能力因素的影响。为了分析受油能力对加油机效能的影响,首先,通过对历史上典型加油机远程部署战例的分析,研究受油能力对加油机作战效能的影响。其次,对加油机机队加受油过程进行详细分析,并在此基础上建立基于受油能力的加油机机队能力模型。通过对单机种加油机机队的加油能力模型和基于受油能力的加油机机队加油能力模型进行分析,分析加油机具有受油能力对加油机机队加油效能的重大影响,从而为加油机设计提供参考。     

Impact of the thermal effect on the load-carrying capacity of a slipper pair for an aviation axial-piston pump

A thermal hydraulic model based on the lumped parameter method is presented to analyze the load-carrying capacity of a slipper pair in an aviation axial-piston pump under specified operating conditions. Both theoretical and experimental results are presented to demonstrate the validity of the thermal hydraulic model. The results illustrate that the squeezing force and thermal wedge bearing force are the main factors that affect the film thickness and load-carrying capacity. At high oil temperature and high load pressure, the film thickness decreases with increasing clamping force due to a combined action of the squeezing bearing force and the thermal wedge bearing force, but the load-carrying capacity will increase. An increase of the film thickness is proven to be beneficial under high shaft rotational speed but especially dangerous as it strongly increases the ripple amplitude of the film thickness, which leads to decreasing the load-carrying capacity. The structural parameters of the slipper can be optimized to achieve desired performance, such as the slipper radius ratio and orifice length diameter ratio. To satisfy the requirement of the load-carrying capacity, the slipper radius ratio should be selected from 1.4 to 1.8, and the orifice length diameter ratio should be selected from 4 to 5.     

Achieving the capacity of half-duplex degraded relay channels using polar coding

In this paper, a novel transmission protocol based on polar coding is proposed for the half-duplex degraded relay channel. In the proposed protocol, referred to as the partial message relaying, the relay only needs to forward a part of the decoded source message that the destination needs according to the exquisite nested structure of polar codes. Theoretically, it is proved that the scheme can achieve the capacity of the half-duplex relay channel under the decode-and-forward （DF） cooperation strategy while enjoying low encoding/decoding complexity. Practically, in order to minimize the global transmission power, the optimization of the power allocation is performed between the source and the relay by using information theoretic tools. Furthermore, a joint iterative soft parallel interference cancellation receiver structure is developed to suit to the proposed scheme. Simulation results show that the proposed scheme outperforms the conventional scheme designed by low-density parity-check （LDPC） codes.     

挠性高稳定度卫星载荷扰动力矩补偿研究

有效载荷或星上运动部件相对卫星平台转动引入的扰动力矩严重影响卫星平台的姿态稳定度和指向精度.为满足卫星姿态高稳定度要求,采用正余弦细分驱动原理对帆板驱动机构(SADA)细分,并利用力矩补偿机构补偿有效载荷运动所引入的扰动力矩.此外,针对补偿机构自身存在的摩擦力矩设计补偿控制律,以改善其力矩输出性能.仿真算例表明设计方案有效.