一种面向电力终端的北斗定位模块研究

基于电力系统对卫星导航定位的自主安全性要求，研究用于电力终端的北斗定位技术，设计了一款用于电力行业终端的北斗定位导航模块，主要包括模块的模拟前端设计、数字信号处理及分析，重点对低功耗小型化设计、提高接收灵敏度设计等进行研究，并对所设计的北斗模块实物进行了实际测试和分析，成果已开始在电力行业试点应用。     

超音速流动中侧向喷流干扰特性的数值模拟

通过与实验结果的比较验证Fluent软件可以用于超音速流动中侧向喷流干扰特性数值研究.使用Fluent软件对超音速流动中不同喷流压力和攻角下侧向喷流干扰特性进行的数值研究表明,超音速流动中,随喷流压力和负攻角增大,喷流前的高压区明显增大,喷流的控制效果更好.喷流包裹作用的影响范围在90°弹面内.喷流压力增大,喷流包裹作用加强,影响范围增大.     

某型飞机座舱盖玻璃后弧花槽裂纹问题的解决方法

分析我军某型现役主力战机飞机座舱盖有机玻璃后弧花槽裂纹产生的原因,提出修理中的解决方法,确定改装后的主要技术参数及装配方法。     

Three-dimensional analysis of relationship between relative orientation and motion modes

Target motion modes have a close relationship with the relative orientation of missile-totarget in three-dimensional highly maneuvering target interception. From the perspective of relationship between the sensor coordinate system and the target body coordinate system, a basic model of sensor is stated and the definition of relative angular velocity between the two coordinate systems is introduced firstly. Then, the three-dimensional analytic expressions of relative angular velocity for different motion modes are derived and simplified by analyzing the influences of target centroid motion, rotation around centroid and relative motion. Finally, the relationships of the relative angular velocity directions and values with motion modes are discussed. Simulation results validate the rationality of the theoretical analysis. It is demonstrated that there are significant differences of the relative orientation in different motion modes which include luxuriant information about motion modes. The conclusions are significant for the research of motion mode identification,maneuver detection, maneuvering target tracking and interception using target signatures.     

Prediction of Group Delay Distribution Around Receiving Point Using Modified IRI Model and IGRF Model

The international reference ionosphere (IRI) model is generally accepted standard ionosphere model. It describes the ionosphere environment in quiet state and predicts the ionosphere parameters within a certain precision. In this paper, we have made a breakthrough in the application of the IRI model by modifying the model for regions of China. The main objectives of this modification are to construct the ionosphere parameters foF2 and M (3000) F2 by using the Chinese reference ionosphere (CRI) coefficients, appropriately increase hmE and hmF2 height, reduce the thickness of F layer, validate the parameter by the measured values, and solve the electron concentration distribution with quasi-parabolic segment (QPS). In this paper, 3D ray tracing algorithm is constructed based on the modified IRI model and international geomagnetic reference field (IGRF) model. In short-wave propagation, it can be used to predict the electromagnetic parameters of the receiving point, such as the receiving area, maximum useable frequency (MUF) and the distribution of the group delay etc., which can help to determine the suitability of the communication. As an example, we estimate the group delay distributions around Changchun in the detection from Qingdao to Changchun using the modified IRI model and IGRF model, and provide technical support for the short-wave communication between the two cities.     

跨声速涡轮静子端壁气膜冷却数值研究

对跨声速涡轮静子端壁气膜冷却进行了数值研究。研究发现涡轮静子端壁存在几个强换热区域：叶片前缘马蹄涡及前缘马蹄涡区域、吸力面马蹄涡分支覆盖区域、通道中靠近压力面侧和尾缘附近及尾缘后区域。针对端壁区域复杂的换热分布,设计了1种新型端壁全气膜冷却布置。通过数值研究对比了在不同进口吹风比情况下的壁面Nu、壁面气膜冷却效果和壁面热负荷。结果表明：存在最佳的进口吹风比,即在前缘Minlet=1.0时,尾缘Minlet=4.0时,端壁区域冷却效果最好。     

高光谱观测卫星高精时间同步方案设计与应用

为了满足星上高光谱相机、全谱段光谱成像仪、星敏感器等时间精度敏感仪器的高精度时间同步需求,高光谱观测卫星上设计了可适应多种精度需求的时间同步方案。对于系统时间,综合通过星地时差集中校时、均匀校时、GPS总线校时、GPS硬件秒脉冲校时等校时方法进行时间修正;对于终端用户,分别给出直接采用广播的进行本地时间修正的时间同步方法、采用广播及内部秒脉冲的时间同步方法、采用广播授时和不同秒脉冲校时方案的地面时间重建算法。利用在轨数据,对卫星星敏感器、全谱段光谱成像仪及可见短波红外高光谱相机的曝光时刻时间重建方法进行了应用说明,并对不同方法的时统误差进行了分析。     

航空发动机试验多系统数据融合设计

航空发动机试验在其研制过程中占比很大。在试验时,各专业系统将相关信息资源共享,协同工作。为了满足航空发 动机地面试验时多系统试验信息共享的需求,对与发动机试验相关的台架测试、台架电气、发动机控制、试验流程管理、试验数据 管理、远程监视、音视频等系统等进行了数据融合设计。该设计以试验数据管理技术和网络通讯技术为核心,针对各系统通讯协 议、格式、速率各不相同的数据流传输特点,采用Winsock、DataSocket、OPC、音视频流媒体及数据库通讯等多种数据通讯技术,实 现了发动机试验多系统数据融合统一管理。结果表明：该设计具有系统适用性强、搜集试验信息全、易于数据管理等特点,可满足 试验技术要求,已保障多种型号发动机完成试验。     

航空圆弧端齿的齿根双圆弧结构设计及优化

针对航空发动机圆弧端齿结构齿根单圆弧连接区域存在比较严重的应力集中问题,提出一种圆弧端齿结构齿根双圆弧设计方法,以改善齿根附近的应力集中现象。文中推导建立了双圆弧设计的基本公式,算例对比分析表明双圆弧设计的齿根最大等效应力比单圆弧设计降低了5.5%。在此基础上,根据EGD-3应力标准和格里森圆弧端齿设计准则,建立圆弧端齿结构的优化模型,采用精英保留遗传算法的优化方法对圆弧端齿进行了优化设计分析,优化结果表明双圆弧优化设计的齿根最大等效应力比单圆弧设计降低了12.3%,同时改善了齿根附近的应力分布状态。