Abstract:This paper focuses on the research on the status of adaptive wing and summarizes from the adaptive compliant leading edge, the adaptive compliant trailing edge and the variable thickness wing, respectively. And the key technology that adaptive wing needs to be solved urgently is put forward, which can provide some technical reference for the design and implementation of adaptive wing structure.

Abstract:The accurate measurement of air data is critical to the navigation and flight control of vehicles. Comparing with the intrusive conventional air data measurement system, the flush air data sensing system could be applied to hypersonic vehicles, stealth vehicles and high angle of attacks vehicles. Based on the development of the flush air data sensing system, different pressure ports arrangements were presented in this paper. And then, advantages and disadvantages of different aerodynamic models and solution algorithms were analyzed. Finally, the failure detection and management of the measure system was summarized.

Abstract:The design of Least Risk Bomb Location (LRBL) is directly related to the flight safety of transport aircraft, and the research on airworthiness compliance verification of LRBL in our country is still in its infancy.According to LRBL airworthiness requirements and AC 25.795-6 ,based on design and layout of structures and systems around LRBL and the secondary effects and countermeasures after the explosion, the research progress of the aircraft structure response characteristics under internal explosive load, impact damage of human, explosion-proof container design and projectile damage caused by explosion fragments is reviewed. The related project studies to study the response of fuselage structures under internal explosive load are described briefly.

Abstract:Aiming at optimal airspace layout of electronic jamming during air fighter’s penetration operation, the range of radar detection under electronic jamming, route safety interval, and effective jamming time under electronic interference were described. In order to achieve the safety penetration of the penetration fighters, to ensure the safety of the jammer itself, and to achieve the purpose of efficient use of airspace resources, the optimal airspace layout model of the electronic jamming machine was established, and Improved Grey Wolf Optimization (IGWO) was used to find the optimal airspace reference point. In order to avoid falling into the local optimum, the linear adjustment parameter in original grey wolf optimization was changed to a non-linear one, and the memory function in the particle swarm optimization was added. The simulation results showed that Improved Grey Wolf Optimization (IGWO) was superior to the original grey wolf optimization algorithm and particle swarm optimization, could quickly find the optimal airspace reference point to complete a specific penetration task, and then designed the optimal airspace of the electronic jamming aircrafts. It also proved that the model was scientific and effective.

Abstract:The probability of our aircrafts being shot down is modeled to improve the safety of penetration flight, and to promote the probability of running task successfully. By improved genetic algorithm, with the probability of being shot down as the fitness function, and the distance between an individual and solution space as punishment function, the best plan can be found. Constrained optimal save strategy is being used to prevent the solution from early convergence. Variable arithmetic hybrid operator can limit the individual in solution space. As the result, after 150 times performance, the best flight can be gotten as O（120，550），A（226.2，495.7），B（345.8，364.3），T（330，180）, whose probability of being shot down is 0.0193.

Abstract:Electromagnetic stealth has an important impact on survivability of aircraft. According to different missions, the aircraft layouts need to be changed correspondingly. In order to study the influence of layout on electromagnetic scattering characteristics for aircraft, four kinds of typical layouts and electromagnetic models of aircrafts were established. And based on Physical Optics method, the RCS curves of different layout aircrafts were simulated numerically, and the distribution characteristics of RCS were also analyzed. Besides, the frequency response characteristics of electromagnetic scattering were studied for conventional and special layout aircraft models. The results show that the aircraft layout determines the distribution of RCS. In the angular domain of nose direction, the electromagnetic stealth performance of layouts A-1, A-2, B, C and D tended to increase oscillatorily, and RCS mean value dropped from 7.7700dBsm to -30.0673dBsm, the RCS mean value of layout B is -10.4347dBsm. While the electromagnetic stealth performance of rearward and circumferential direction of different layouts increase in turn. The RCS mean values in rearward direction are reduced from 22.7025dBsm of conventional layout to -25.0938dBsm, and RCS mean values in circumferential direction are reduced from 7.0391dBsm to -15.1373dBsm. In high frequency region, the increase of frequency has small effect on distribution of RCS curves, but oscillation of curves is more obvious, and RCS arithmetic mean decreases with the change of frequency.

Abstract:The matrix cracking along the fiber direction may take place at a tensile load near the hole edge.The matrix cracking can blunt the hole and alleviate the stress concentration. In order to accurately simulate this phenomenon,a three-dimensional finite element model was established based on CDM.A modeling method for different arrangement of grid in laminate was proposed.Surface-based cohesive contacts was established to simulate the inter-ply delamination characteristic.Simulate the open-hole tensile damage of composite laminates with stacking sequences of [0/902/0]S and [0/90/-45]S.The results indicate that the progressive damage process and ultimate tensile strength of the composite laminates with different material system and layer parameters at tensile load could be predicted by this model,The prediction accuracy of this method was satisfactory by comparison with known experimental data in literatures,which was proved the analysis method was valid..

Abstract:In order to improve the competitiveness, optimizing the fuel economy and competitiveness of civil turbofan engines is becoming the research highlights recently. In this paper, the comparison analysis of cycle parameters is carried out for different configurations such as advanced turbofan (ATF), geared turbofan (GTF) and intercooled recuperated aero-engine (IRA). The technical advantage of different configurations is determined. The research results show that the specific fuel consumption at the cruise uninstall condition of GTF configuration is decreased by 2.5% compared to that of ATF configuration. The specific fuel consumption at the cruise uninstall condition of IRA configuration is decreased by 11.97% compared to that of ATF configuration, and which is decreased by 9.7% compared to that of GTF configuration. Comparison to ATF and GTF configurations, the stage number of high pressure compressor and high pressure turbine can be reduced to shorten the core engine length, and this also diminish the design difficulties of high pressure compressor.

Abstract:A series of approaches have been developed to identify the short take-off performance of tilt-rotor aircrafts which tilt their nacelles to implement short take-off. The approaches include how to confirm the minimum tilt angle of the nacelles, and the formulas suitable to calculate lift-off speed and take-off length are also developed. These methods are adopted in the design of a certain tilt-rotor aircraft during the preliminary design stage, moreover, the effects of airport altitude and weather conditions on short take-off performance are also researched. The results are reasonable, which indicates that these approaches are useful and of great value in practice.

Abstract:Abstract： The features, advantages and exiting problems of autogyro are analyzed thoroughly in this paper. Based on the aerodynamics model of the variable speed main rotor, propeller and airframe, the flight dynamics model of autogyro is built. ELA-07AGRO is taken as the sample autogyro, which is modeled and trimmed; then the stability is analyzed. Besides, the manipulation variables, Euler angles and flight modes are calculated using the flight test data and compared with results of the model. The comparisons shows that in the regular speed range, the longitudinal control of the sample autogyro needs to be pushed forward monotonously; the lateral control needs to be mildly pushed left monotonously; the rudder is turn to left; the throttle first decrease and then increase. As for the stability of flight modes, the spiral and Dutch-roll model is slowly divergent, and the short period, phugoid, rotorspeed and roll subsidence modes are stable. In conclusion, it can be seen that the sample autogyro has good stability. The results of this paper can provide theoretical reference for the unmanned flight control of this kind of aircraft, and it can also be used for flight safe driving provides useful guidance.

Abstract:无人机地面滑跑起飞阶段是飞行过程中的危险阶段,其受力情况复杂,动力学特性与空中飞行时略有 不同。以某轮式起降无人机为研究对象,根据起落架的机械特性和几何关系将起落架等效为一个弹簧阻尼系 统,并在Matlab/Simulink中集成无人机本体、起落架、发动机、舵机、控制系统等模型,建立的仿真平台模拟无 人机滑跑起飞全过程。结果表明:该轮式起降无人机在滑跑起飞过程中压着机头滑跑,始终对准航向,滚转姿 态变化很小;在大油门推力作用下无人机增速较快,抬前轮后瞬间主轮离地,并以稳定的速度爬升,较短时间内 可以到达安全高度。

Abstract:The fuel injection ring is an important part of the micro-turbojet engine. The uniformity of fuel injection quantity determines the uniformity of the temperature field in the combustion chamber. At this stage for micro-turbojet injection ring uneven fuel injection problems，This paper intends to compensate for the influence of pressure loss through the use of unequal-diameter needle structure to ensure the uniformity of injection quantity. By using CFX software to simulate the experiment of three-dimensional flow field inside the fuel injection ring, And calculates the outlet flow rate, outlet velocity and the pressure change of the entire internal flow field of injection needle on the injection ring body, and finally compares with the experimental results; Based on this simulation method, the results show that the scheme of unequal injection nozzle can improve the problem of nonuniform injection of fuel injection ring. According to the calculated results, we can lay the foundation for the study of the internal flow field of the injection ring and make the analysis.

Abstract:There is eccentric error between the geometric center of the gear blank and the axis of the rotary table during the aero gear grinding process. The machining precision of grinding tooth accuracy is reduced. In order to improve the precision of gear grinding, according to the working principle of CNC grinding wheel grinding machine, the eccentric error of the installation is proportional to the deviation from the single pitch and the total cumulative deviation of the tooth distance by analysis. The compensation method of installation eccentricity error is put forward. The mathematical model of offset error compensation is established. The feed compensation increment of the grinding wheel in the two directions of X and Y is obtained through the mathematical model. Taking the YK73125 CNC grinding wheel grinding machine as an example, the eccentric error compensation experiment is carried out. The single pitch limit deviation is reduced by 0.9 and 1.6 on left and right tooth surfaces. The total cumulative pitch error is reduced by 49.6 and 43.3 on left and right tooth surfaces. The experimental results show that the installation eccentricity error compensation for gear grinding can effectively reduce the total deviation of the single pitch deviation and the cumulative tooth distance.

Abstract:In our country, the airworthiness certification and aviation technology are lagging far behind，the development of domestic onboard flame arrester has just been included into the agenda. Hence, based on the analysis of the reason of the pressure drop of the airborne flame arresters, a method suitable for calculating the pressure drop of the airborne flame arresters is proposed. Based on the comparison with the experimental results and the verification of the correctness of the method, according to arresters technical requirements, analyze the pressure drop of flame arrestor element with different characteristic dimension under air flow and fuel overflow, and discuss the influence of various factors on the pressure drop of airborne flame arresters. The results indicate that the proposed method can provide useful reference for engineering design, calculation and selection of airborne flame arresters.

Abstract:Taking aviation SMS as key words, related Literature periodical is searched form CNKI. First of all, the retrieval data are processed by STAI, and dissimilarity matrix is constructed. Then key words was analyzed by means of centrality, cluster multi-dimension and core-periphery analysis of Social Network Analysis, and the current status and trend of aviation safety management is studied, which gives a reference for the study of SMS realm in depth.

Abstract:With the mode of multi-breed and small batchis becoming popular in the aviation research and development enterprise, the traditional aviation development companies face new challenges in business management processes. We analyze the status quo of business management processes in aviation development enterprises. And study the relationship between the IDEF0’s function model and the business process optimization of the aviation development enterprise. By optimizing the IDEF0 functional model, we have designed a top-level model and a phased model for the business management of aviation development enterprise. Then the models have been applied combining the optimization of business management in engineering and technology department of an aviation development enterprise.

Abstract:Effectiveness evaluation of maintenance support system is one of the most important measures in the fine and standardized management of military aircraft. A scientific effectiveness evaluation of maintenance support system is the foundation of fine protection and the guarantee of improving the fighting capacity. Targeted at the issue of the maintenance support system effectiveness evaluation of the military aircraft, the thesis firstly summarized effectiveness evaluation systems of maintenance support system, and a effectiveness evaluation model was proposed based on PSO-ELM. Finally, the feasibility of the method was verified through analysis, which can provide reference for the effectiveness evaluation of maintenance support of military aircraft.

Abstract:The pulse signal is an important basic parameter in metrology support for aviation equipments,and the calibration device of oscilloscope calibrator is an important standard for measuring the rise time of pulse signal. This paper introduces the composition of the measurement standard for OsciIloscope calibrator,analyzes the measurement method of high speed pulse rise time,and evaluates the uncertainty of the measurement results. In this paper,the uncertainty analysis of the pulse rise time can be used as a reference for compiling the measurement standard report and uncertainty analysis of osciIloscope calibrator in aviation test and calibration.

Abstract:Generalization of support equipment is the very important way to reduce the scale of supportment and maximize the effectiveness of supportment. Selection of generalization support equipment is to select qualified suppliers and models from carrying out initial use and evaluation in the real use environment. This paper aims at the requirement of equipment system''s support capability .Firstly, establish the evaluation index system of general support equipment capacity. Secondly,design the experimental scheme and process suitable for evaluation from analysing the design requirements and principles of competitive test. At the same time,give the general process of how to convert of the evaluation. At last,establish the method to determine the weight of unified and bidding test based on relevance degree.

Abstract:The maintenance process greatly affects the maintenance support , and the influence of the air force’s combat effectiveness. Maintenance support process research can help us in our understanding of principles and methods making the maintenance support process under different environment, to achieve higher efficiency of maintenance reliability and economy. This paper use AHP to have quantitative research on the evaluation system whose core parameters is maintenance system at grass-roots level. As it analyzes the weight of each index of evaluation system, finally obtaining a result that in different maintenance system, the sortie generation rate and fleet of mission success have a huge weight on the system, and in the secondary indicators of evaluation system, planning guarantee has a huge weight on it, which shows that the planning guarantee ability at grass-roots level is a significant influence factor in maintenance operation system. And it establishes a strong basis to optimize maintenance operation system at grass-roots level.

Abstract:Condition-based maintenance (CBM) focuses on specific system operation condition to evaluate the real status of monitored equipment. CBM overcomes the blindness of maintenance, and is able to effectively reduce accidental failures caused by insufficient maintenance and waste of resources by the excess. This paper proposes a multi-unit system non-periodic preventive maintenance plan optimization method which is based on state. The concept of "opportunity maintenance threshold" is introduced, and the expression of different maintenance mode transition probability is optimized. We combine multiple maintenance work in accordance with the opportunity maintenance threshold and propose the expression of different maintenance mode transition probability and the objective function on the basis of Markov Decision Process Theory. Through the example analysis, the proposed optimization model can decrease the preventive maintenance activities, save maintenance time and funds, and provide reference for system preventive maintenance strategy decision.

Abstract:As an important part of aircraft power supply system, it is particularly important to realize cable fault online diagnosis and improve reliability. This paper designs a cable fault online detection and location device with the 500MHz board level rate based on FPGA by Spread Spectrum Time Domain Reflectometry (SSTDR), according to the characteristics of aircraft cable faults and the specification of aircraft cable detection. The instrument can realize the online detection and location of the open circuit, short circuit and intermittent arc of cables, and has the advantages of high positioning accuracy and good real-time performance. Using this device to monitor the health state of the cable fault on-line and realize the detection of the intermittent fault which is difficult to reappear, it can improve the efficiency of ground operation and afterwards maintenance to save a lot of manpower and material resources and has higher engineering value.