Table of Content

30 July 2016, Volume 37 Issue 7

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Paper

Research on Digitized Modeling Method of Riding Road of Vehicle

WANG Hong-yan， WANG Qin-long， RUI Qiang， LI Rong-li， ZHANG Jing， LUO Tao

2016, 37(7):  1153-1160.  doi:10.3969/j.issn.1000-1093.2016.07.001

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Digitized modeling method of riding road of vehicle is researched for improving the accuracy of vehicle virtual test results. Dual-track real profilometer is used to measure the periodic medium wave and long wave roads. The credibility and veracity of measuring method are verified by comparing actual measuring data with wave curves which are built based on the design parameters of road outline. Then two kinds of random roads, i.e., residue road and gravel road, are measured by using a dual-track real profilometer, and the actual road roughness data is obtained. Power spectral density (PSD) of actual measuring data is estimated by Welch algorithm based on modified periodogram method, and the rank of measuring random road is assessed according to GB/T 7031—2005 national standard. The 3D random road models are built by means of harmony superposition method, of which PSD is consistent with actually measured data, and its credibility is verified consequently.

Path Following of Incomplete Symmetric Unmanned Amphibious Platform

SUN Wei, HUA Yu-long, CHI Bao-shan, LIU Guo-qiang

2016, 37(7):  1161-1169.  doi:10.3969/j.issn.1000-1093.2016.07.002

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The path following of incomplete symmetric unmanned amphibious platform in shallow water is discussed in order to improve its reliability and maneuverability. The influence of water depth on hydrodynamic derivatives is analyzed, the hydrodynamic derivatives is corrected, and a more accurate model is established. The path following errors are described in Serret-Frenet coordinate after the transformation of model and reference path, and then two cascade subsystems are obtained, namely the position following subsystem and the course and surge velocity following subsystem. The velocity following subsystem is proved to be equivalent to the whole system based on cascade theory. A global stable controller of the velocity following subsystem is designed based on backstepping method. The mathematic simulations and lake trial were carried out, which illustrate that the global stable controller is available for the incomplete symmetric unmanned amphibious platform to track a straight-line and a circle paths.

Rapid Scheme Design of Firearms Based on Case-based Reasoning

WANG Guo-xin， SHI Xue-hai， YAN Yan， MING Zhen-jun， HAO Jia

2016, 37(7):  1170-1179.  doi:10.3969/j.issn.1000-1093.2016.07.003

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To improve the design knowledge reuse level and retrieval precision of case-based reasoning method in firearm scheme design, a design scheme and a revise method are proposed based on case-based reasoning for variant design process. A case-based reasoning framework is firstly established, including knowledge base, main reasoning engine, case retrieval module and rule-based revise module. For three different design requirements, a corresponding similarity calculation method is then proposed to improve the case retrieval accuracy. Similarity cases obtained in retrieval phase are quantifiably and adaptively revised to get the final design scheme by introducing the concept of rule knowledge. A firearm rapid scheme design prototype system is developed, and a barrel design example is presented to verify the accuracy of retrieval process and the effectiveness and practicality of the proposed method.

Trans-scale Polycrystalline Finite Element Simulation of Radial Forging Process for Barrel and Prediction of Texture

XU Xiao, FAN Li-xia, WANG Ya-ping, DONG Xiao-bin

2016, 37(7):  1180-1186.  doi:10.3969/j.issn.1000-1093.2016.07.004

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Radial forging is an advanced manufacturing method for barrel. After the polycrystalline material of barrel is forged, the preferred orientation of the materials grain forms texture which presents the anisotropy phenomenon macroscopically. This phenomenon can not be simulated using the common finite element analysis (FEA) method. A macroscopic barrel radial forging FEA model and a microscopic polycrystalline plasticity FEA model are established based on ABAQUS code, the mathematical software Matlab and the programming language Python. The multi-scale method is used to program the boundary conditions inheriting from macro-mechanics state to meso-mechanics state which make the size of grain as reality. The pole figures of forged polycrystalline material and the orientation distribution function (ODF) figures are drawn by Matlab, which are used to analyze the orientation change of grain in the microscopic polycrystalline plasticity FEA model. The XRD experiment is used to validate the accuracy of the simulated results. A research method to connect macroscopic forging process and microscopic texture is presented, which provides a new way to predict the mechanical property of barrel after forging.

Multi-objective Optimization on Aerodynamic Shape of Projectile with Twisted Empennages

CHEN Liang， LIU Rong-zhong， GUO Rui， ZHAO Bo-bo， LIU Lei， YANG Yong-liang

2016, 37(7):  1187-1193.  doi:10.3969/j.issn.1000-1093.2016.07.005

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The twisted empennage structure is applied to the aerodynamic configuration design of hedgehopping terminal sensitive projectile for improving its performance. In order to obtain higher balance rotational speed and lower drag coefficient, a multi-objective optimization design of the aerodynamic shape of projectile with twisted empennages is developed based on the wind tunnel tests. The computational fluid dynamics, orthogonal experiment design, stepwise regression analysis and genetic algorithm are applied, and the Pareto solutions of the empennage shape are provided. The results indicate that the twisted empennage structure can significantly improve the aerodynamic performance of projectile. An aerodynamic parameter surrogate model is established accurately to predict the projectile drag coefficient and balance rotational speed, and the influences of empennage structural parameters on the proposed model can be further obtained. The Pareto solutions based on the multi-objective genetic algorithm display a good performance on the increase in rotational speed and the reduction in drag.

H_∞ Guidance Law Accounting for Dynamics of Missile Autopilot

MENG Ke-zi, ZHOU Di

2016, 37(7):  1194-1202.  doi:10.3969/j.issn.1000-1093.2016.07.006

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In order to intercept the maneuvering targets and overcome the adverse effect of the missile autopilot’s dynamics on the guidance performance, this paper aims to propose a H_∞ robust guidance law with the dynamics of the autopilot considered. The third-order linear time-varying state equation for the integrated guidance and second-order dynamics of autopilot is expressed as a polytopic LPV system. A novel H_∞ robust guidance law, in the form of linear state-feedback with parameter-dependent gain, is designed using LMI method. The coefficients in the parameter-dependent gain are obtained by solving a convex optimization problem with LMI constraints. Simulation results indicate that, even if the target’s acceleration is not known, the H_∞ guidance law can still achieve strong robustness and obtain high guidance precision.

Online Calibration of IMU errors of Inertial Navigation System Based on Innovation-based Adaptive Filtering

WANG Jie， XIONG Zhi， XING Li， DAI Yi-jie, HUA Bing, LIU Jian-ye

2016, 37(7):  1203-1213.  doi:10.3969/j.issn.1000-1093.2016.07.007

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Considering the flight environment and motion characteristics of aerospace vehicle, the noise statistical characteristics of the navigation sensors’ errors can’t be completely known, which may seriously degrade the filtering precision or even cause filtering divergence if the conventional Kalman Filter is used. An online calibration method for IMU errors of SINS based on the innovation-based adaptive filtering is proposed, which can overcome the weakness of that the conventional Kalman filter should know the statistical characteristics of the system noise and measurement noise in advance. An error calibration model of 27-D high-order state variables is established, including the installation error, scale factor error and random constant error of IMU, and an online calibration algorithm based on the innovation-based adaptive filtering is proposed, which can adjust the covariance matrices of system noise and measurement noise dynamically. Simulation shows that the proposed method performs higher calibration accuracy and better navigation performance compared to the conventional Kalman filter and Salychev O adaptive filtering algorithm. It is proved by the field test that this method could calibrate the IMU residual errors effectively, improve the navigation accuracy and bring a great convenience for engineering application.

Measuring and Numerical Simulation of Attenuation of Planar Shock Wave in PMMA

ZHANG Shi-wen, LONG Jian-hua, JIA Hong-zhi, JIN Shan

2016, 37(7):  1214-1219.  doi:10.3969/j.issn.1000-1093.2016.07.008

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The attenuation rule of shock wave in the materials is studied. A polyvinylidene fluoride (PVDF) film pressure sensor is used to obtain the attenuation data of shock wave driven by plane-wave lens-driven explosives in PMMA material. The plane-wave lens-driven explosive with high and low detonation velocities is numerically modeled, and the calculation termination due to the reversal of largely deformed explosive grid overflowing the metal cylinder is dealt with. Comparative analysis of simulated and experimental results shows that the shock wave traveling through 50 mm thick PMMA is attenuated from 7.4 GPa to 4.02 GPa. The research provide the experimental data for the attenuation of shock wave in PMMA, and the matters needing attention to the installation of PVDF film pressure sensor are presented.

Study of Beam Scheduling for Battlefield Surveillance Phased Array Radar

SHI Xiao-bin, GU Hong, LIU Yan-hua, HUANG Jin-jie

2016, 37(7):  1220-1228.  doi:10.3969/j.issn.1000-1093.2016.07.009

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Beam scheduling strategy of maneuvering target track and track-and-search (TAS) in strong clutter environment for battlefield surveillance phased array radar is the hot spot in current research. The ground interacting multiple model joint probability data association tracking algorithm based on the prior information about target path and ground clutter is established. The dynamic TAS beam scheduling is achieved based on the target threat level and tracking accuracy of threat target. The TAS beam scheduling strategy based on the GIMMJPDA tracking algorithm, high threaten priority and target tracking accuracy for battlefield surveillance phased array radar has high efficiency of time utilization, which can be used in engineering application.

SINS/DVL Integrated Navigation Algorithm Based on Transversal Coordinate Frame in Polar Region

ZHANG Fu-bin, MA Peng, WANG Zhi-hui

2016, 37(7):  1229-1235.  doi:10.3969/j.issn.1000-1093.2016.07.010

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The traditional north-pointing inertial navigation mechanics arrangement of inertial navigation system is not suitable for using in the polar region due to the rapid convergence of geographical longitude at high latitudes so the establishment of the heading relative to the longitude is more and more difficult, and the singular value in geographic poles exists. Focusing on the above problem and the autonomy and navigation accuracy requirements of autonomous underwater vehicle (AUV) during navigation, a SINS/DVL integrated navigation scheme based on transversal frame in polar region is proposed. The definition of the transverse earth/geographic coordinate frame and its conversion with conventional navigation frame are presented. The mechanizations of inertial navigation based on transversal frame in polar region are derived by analogy with the traditional north-pointing navigation mechanizations. A SINS/DVL integrated navigation algorithm based on Kalman filter in polar region is designed. The simulation is carried out to analyze the proposed integrated navigation system. The results indicate that the navigation method can restrain effectively the increase in azimuth misalignment angle, and the navigation accuracy can satisfy the navigation requirement of AUV in polar region.

The Multi-body System Dynamics Modeling of Wave-driven Underwater Vehicle Based on Kane Method

DU Xiao-xu, CUI Hang, XIANG Zhen-hui

2016, 37(7):  1236-1244.  doi:10.3969/j.issn.1000-1093.2016.07.011

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A coordinate system for wave-driven underwater vehicle is defined based on multi-body system dynamics theory. The kinematics analysis of the whole system is performed by choosing the appropriate generalized coordinates, while the velocities and acceleration are deduced, and the expressions of partial velocities and partial angular velocities are deduced based on Kane’s method according to the dynamic analysis of the whole system. The generalized inertial force and generalized active force of the whole system are calculated. A multi-body system dynamics model of wave-driven underwater vehicle is established by taking the calculated results into the Kane’s equations. The force analysis of the proposed model focuses on the wave force and the additional mass force of multi-body system besides inertia force, inertia moment, gravity, buoyancy and hydrodynamic forces. The wave-driven underwater vehicle is simulated. The simulated results show that the proposed modeling method is valid.

Improved Test Method for Shielding Effectiveness of Enclosures in Reverberation Chamber

LIU Yi-fei, CHEN Yong-guang, CHENG Er-wei

2016, 37(7):  1245-1251.  doi:10.3969/j.issn.1000-1093.2016.07.012

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The principle of testing the shielding effectiveness (SE) of enclosures in reverberation chamber (RC) using frequency-stirred method is introduced briefly. Based on this, the shielding effectiveness of a slotted enclosure is measured. As to the low metering accuracy exposed in test, a combined stirring test technology is proposed, which can significantly increase the sample size in stirring bandwidth, thus reducing the uncertainty of test result. A new method based on digital low-pass filtering is presented to get the mean curves of electric field. The proposed method can effectively retain the peak information and obtain the desired smooth of electric field, so it enhances the accuracy of data processing. Compared with the two method, the combined stirring test method needs to combine mechanical stirring with frequency stirring, which is more suitable for large cavity test. The digital low-pass filtering is careless of the sample size and does not need additional test equipment.

Effects of Electroforming Parameters on Fatigue Properties of Cu-based Planar Micro-spring

CAO Quoc Dinh, XU Ning, LI Cheng-yuan, ZHANG Xin-ping

2016, 37(7):  1252-1257.  doi:10.3969/j.issn.1000-1093.2016.07.013

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Micro-spring is an important actuating component used widely in microelectromechanical systems. It is important to develop micro-forming techniques for manufacture of micro-springs with high-fatigue life. The effects of duty cycle, current density, and power properties on the quality of micro-electroforming planar micro-springs are studied. The process is optimized using an orthogonal experiment in order to achieve the high dimensional accuracy and fatigue properties of the planar micro-springs and meet the demand of microelectromechanical systems. The result shows that the fatigue property of micro-spring decreases as the duty cycle increases. Fatigue property of planar micro-spring prepared by double pulse power is superior to the one that prepared by direct current power and single pulse power. The optimal process is to use double pulse power, 3 A/dm² current density, 10% positive duty cycle, and 10% negative duty cycle. The fatigue life of planar micro-spring can reach 517 times under the constant displacement of 0.2 mm.

Research on the Calculation Methods of Fluid Force in Pilot Stage of Jet Deflector Servo Valve

YAN Hao， KANG Shuo， WANG Feng-ju， LI Chang-chun， HUANG Jing

2016, 37(7):  1258-1265.  doi:10.3969/j.issn.1000-1093.2016.07.014

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In order to analyze the fluid force in the pilot stage of jet deflector servo valve, an orifice model based on the rectangular nozzle and receiver of jet plate in pilot stage is established, and a simplified formula of fluid force is obtained. From the perspective of jet flow field, a two-dimensional internal flow field model of jet deflector pilot stage is established. And the momentum theorem method and the differential pressure method are presented to calculate the steady-state fluid force based on the simulated discrete data. An automatic test system for measuring the fluid force in pilot stage is designed. The results show that the calculated results based on simulated discrete data are basically consistent with the theoretically calculated and experimental results.

Research on Thermal Fatigue Failure Mechanism of Aviation Electrical Connectors

LUO Yan-yan, LIU Xu-yang, HAO Jie, WANG Zhen, LIU Lei, LIN Xiao-ming

2016, 37(7):  1266-1274.  doi:10.3969/j.issn.1000-1093.2016.07.015

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Jack of electrical connectors is an elastic element. It is easy to show thermal fatigue and stress relaxation phenomenon under the effect of alternating thermal stress, which affects the contact reliability of electrical connectors. A thermal fatigue test scheme is proposed, and a test circuit is designed for experiment. The thermal fatigue failure mechanism of electrical connectors is analyzed. The test result shows that the value of contact resistance increases slowly with the increase in the number of thermal cycles. The macroscopic reason is that the aperture of jack increases and the contact pressure between contacts decreases. During test, the temperature difference or temperature change rate will accelerate the growth of contact resistance. Based on the metallographic analysis of jack after experiment, it is found that the change of microstructure (the crystal size and slip line density increase, the difference of slip direction is enhanced) is the fundamental reason to lead to the stress relaxation phenomenon of jacks and the contact reliability degradation of electrical connectors. The comprehensive effect of the temperature difference and temperature change rate on the performance degradation of electrical connectors depends on the “confrontation” between slip line density and slip direction number.

Complex Modal Evaluation of NVH Characteristics of Disc Brake

HUANG Ze-hao, LIU Tong, LEI Wei, WAN Xin

2016, 37(7):  1275-1281.  doi:10.3969/j.issn.1000-1093.2016.07.016

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A disc brake nonlinear finite element model is established. Noise vibration and harshness (NVH) characteristics of disc brake are evaluated by the complex mode analysis from the multiple dimensions of negative mode, frequency, damping ratio, modal coupling, modal strain energy and so on. The results show that the different parameters can reflect the instability of modal model. The model exists an instability mode in the range of 1~15 kHz frequencies. Big complex eigenvalue real part, high negative damping ratio, and poor modal stability exist in the ranges of 1~3 kHz and 12~13 kHz. Unstable modal could couple with adjacent modal easily, which increases the incidence of brake noise.

Virtual Sliding Mode Control-based Attitude Estimation for Non-cooperative Spacecraft

YU Xiao-ting， YU Feng， HE Zhen， XIONG Zhi， WANG Zhen-yu

2016, 37(7):  1282-1290.  doi:10.3969/j.issn.1000-1093.2016.07.017

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A virtual sliding mode control design method is proposed for the nonlinear attitude estimation of non-cooperative spacecraft. The real-time observations outputted by the stereo vision system are used as the inputs of the virtual sliding mode controller, and the spacecraft attitude dynamics mathematical model is taken as a control object of the virtual controller. The virtual control torque is calculated by using the sliding mode variable structure controller. The virtual spacecraft attitude and the observed attitude are synchronous, and the virtual spacecraft attitude is the estimated value of attitude parameter of the non-cooperative spacecraft. Simulation result shows that the proposed estimation algorithm based on virtual sliding mode controller performs better than the extended Kalman filtering algorithm. The application of sliding mode boundary layer control achieves a good balance between the robustness of variable structure control and the smooth control chattering.

Comprehensive Review

The Corrosion Status of Amphibious Vehicles along the Coast and Integrated Corrosion Control Technology

HUANG Yan-bin， ZHOU Ke-ke, BA Guo-zhao, SHI Xiao-jun, LIU Qian

2016, 37(7):  1291-1298.  doi:10.3969/j.issn.1000-1093.2016.07.018

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The corrosion status of amphibious vehicles is comprehensively introduced for the usage of amphibious vehicle in marine environment. The integrated corrosion control theories and anti-corrosion design principles of amphibious vehicles are proposed according to corrosion problems and laws. This paper highlights Al-Zn-In-Mg-Ga-Mn sacrificial anode materials for amphibious vehicle, abrasion resistant ceramic coating, composite anticorrosion coating technology, potential matching technology of dissimilar metals, polymer sealing anti-corrosion technology, and special corrosion protection technology. The whole process of system-wide corrosion control ideas is set up, and a technological procedure of prevention, control and governance is developed. The supporting technology for corrosion control and maintenance support is established, and the theoretical system of corrosion control is improved from the top-level.

Progress and Key Points for Guidance of Multiple Launch Rocket Systems

YANG Shu-xing

2016, 37(7):  1299-1305.  doi:10.3969/j.issn.1000-1093.2016.07.019

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The development process of multiple launch rocket systems (MLRSs) is reviewed, and the three development phases of extended range, improved firing dispersion and guidance implementation of MLRS since World WarⅡ are introduced intensively. The features of MLRS are summarized as well, including multiple launch tubes, spinning of projectile body, large length-diameter ratio, short-time and high thrust motor , curved trajectory and static stability design. The advantages and challenges for guided rocket projectiles are discussed. Several issues, such as strapdowninertia navigation, dynamic stability, trajectory programming and control, advanced solid rocket motor and single conductor wire launch control, which should be focused on and solved in the future investigation, are proposed.

Research Notes

An Approach of Characterizing the Degree of Spatial Color Mixture

CHU Miao， TIAN Shao-hui， YU Jun， HU Zhi-yi

2016, 37(7):  1306-1311.  doi:10.3969/j.issn.1000-1093.2016.07.020

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The digital camouflage technology is a new form of camouflage technology, which is convenient for automated design and construction. It converts the backgrounds of targets to mosaic pictures by means of computer technology. The new camouflage pattern arranges the mosaic blocks with different colors on a camouflage surface according to certain rules, which breaks down the smoothed edges of traditional camouflage pattern. The digital camouflage technology has more remarkable camouflage effect compared with traditional technology. Spatial color mixture is one of the main features of digital camouflage distinguishing from other forms，and is also a key approach to improve disguise effect for digital camouflage. However, the spatial color mixture research on digital camouflage is relatively lack at home and abroad, and cannot provide enough support for the research on digital camouflage design. An effective parameter, spatial-color-mixture ratio, is proposed to characterize the degree of spatial color mixture through the analysis of spatial color mixture progress of digital camouflage. The characterization method was proved to be feasible and effective in practice, which could provide theoretical support for the subsequent work of digital camouflage design.

Research on Measuring Method of Nutation Angle of Projectile Based on Trajectory Tracking with High Speed Photography

WANG Bao-yuan, SHAO Xiao-jun, LIU Peng-ke, HENG Gang, CHAO Hong-xiao, LIU Jun

2016, 37(7):  1312-1316.  doi:10.3969/j.issn.1000-1093.2016.07.021

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The nutation angle of projectile is one of the important factors which influence the firing dispersion, and has been a hot issue in the gun research field. In order to get the measurement result of nutation angle near the exit position of projectile, the trajectory tracking method with high speed photography is used to research the nutation angle of projectile. A trajectory tracking system is presented with the high speed photography and the trajectory tracking mount. The image of the projectile flight trajectory is recorded, and the nutation angle of the up-and-down nutation of projectile is got by means of the image analysis software. An example of a gun projectile is demonstrated with the trajectory tracking system, and the rule of up-and-down nutation of projectile near exit position is obtained. The data dispersity of nutation angles for different projectiles is large, and the maximum nutation angle of the first projectile is -5.2°. It is shown that the trajectory tracking method is a perfect method for getting the measurement result of the nutation angle.

Reliability Evaluation Based on Hierarchical Bootstrap Maximum Entropy Method

XIA Xin-tao, YE Liang, LI Yun-fei, CHANG Zhen

2016, 37(7):  1317-1329.  doi:10.3969/j.issn.1000-1093.2016.07.022

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A hierarchical bootstrap maximum entropy evaluation model is proposed to analyze the life reliability of mechanical products under the condition of small samples without any prior information. Adequate sample data is obtained by using bootstrap method to re-sample the current zero-failure data samples. Based on maximum entropy method, the different Lagrange multipliers can be obtained by changing the number of samples. In order to get the interval estimation values of Lagrange multipliers, the bootstrap method is used again to re-sample the small sample data of Lagrange multipliers. The probability density functions and reliability functions are achieved by carrying on permutation and combination for the upper and lower limit values of each Lagrange multiplier, so the interval estimation values of reliability functions can be gained using minimum uncertainty principle. Experimental investigation shows that the hierarchical bootstrap maximum entropy evaluation model can effectively solve the reliability evaluation problem for zero-failure data of small samples with known or unknown probability distributions.

Research on Operational Safety of Driving System of Continuous Transonic Wind Tunnel

ZHANG Wen, ZHOU En-min, LIU Kai, CHENG Song, LIU Feng

2016, 37(7):  1330-1336.  doi:10.3969/j.issn.1000-1093.2016.07.023

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In order to enhance the operational safety of driving system in continuous transonic wind tunnel, the effects of closed-circuit configuration on airflow temperature rise and wind tunnel tube pressure loss is analyzed based on construction, debugging and operation of 0.6 m×0.6 m continuous transonic wind tunnel. The safety features of shafting, surge and Mach number control for axial compressor used in wind tunnel are researched. The test results show that the performance of heat exchanger meets the requirement of axial compressor operation and total temperature in wind tunnel. The experimental basis of operation parameter alarm threshold values of axial compressor shafting and setting of anti-surge curves is achieved, and the critical speeds of torsional vibration are measured. The flow rate and pressure ratio at 100 kPa total pressure are used for the anti-surge curves of axial compressor, and Mach number can be controlled by the rotational speed of axial compressor and the position of mechanical central part.

The Influence of Constrained Layer Damping on Modal Parameters of Thin Cylindrical Shell

LI Hui， ZHANG Lin-lin， CHANG Yong-le， WEN Bang-chun

2016, 37(7):  1337-1344.  doi:10.3969/j.issn.1000-1093.2016.07.024

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The influence of constrained layer damping (CLD) on the modal parameters of thin cylindrical shell (TCS) is investigated. In order to fully understand the vibration characteristics of TCS, the natural frequencies and modal shapes of TCS are roughly obtained by finite element method. An experiment system is established to measure the modal parameters of the shell with constrained layer with high accuracy and efficiency, and the corresponding test methods and procedures which are suitable for measuring the modal parameters of the shell with or without constrained layer are also proposed. CLD material is made into the annular slices with different sizes, and the modal parameters of TCS with or without constrained layer are accurately obtained. Based on the measured results, the influences of varied dimensional parameters of such constrained layer on natural frequency, mode shape and damping of the shell structure are analyzed in details. It is discovered that CLD may reduce the natural frequency of TCS, but it can effectively improve its damping characteristics.