15 July 2023, Volume 42 Issue 13
    

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  • Debonding damage recognition of bonding interface based on local internal resonance of defects
    LI Zhihang, XIAO Li, QU Wenzhong
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 1-9.
    Abstract ( 355 ) Download PDF ( 232 )   Knowledge map   Save
    The interface debonding of bonded structures will lead to the destruction of structural integrity, so it is of great significance to effectively detect and evaluate the interface debonding. In this paper, a debonding recognition method for bonding interface based on internal resonance of local defect is proposed. Based on a two degree of freedom (2-DOF) nonlinear model of local defects in the bonding interface, the mechanism of the local internal resonance of the interface debonding defects was analyzed by using the multi-scale method, and the specific excitation conditions were determined for the identification method of the internal resonance damage. Experiments were performed on a bonding aluminum beam. Two surface-bonded piezoelectric transducers were used to generate continuous sinusoidal excitation, and receive corresponding wave signals, and the spectral analysis of the response signals was conducted. The adhesive interface debonding identification was carried out by analyzing the saturation phenomenon the two-to-one internal resonance of local defects in the spectrum. The results of numerical simulation and experiment demonstrated that the internal resonance would appear when bonding structure was subject to specific excitation conditions. The internal resonance of local defect can amplify the nonlinear characteristics of the defect, improve the signal-to-noise ratio, gain the detection ability under noise, and effectively identify the debonding damage of the bonding interface.
  • Equivalent mechanical properties of spiral skeleton composite flexible low-temperature pipeline based on NIAH
    YING Xipeng1, GENG Dongling1, CAO Huixin1, ZHANG Kailun1, BU Yufeng1, YANG Zhixun2, YAN Jun1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 10-16.
    Abstract ( 339 ) Download PDF ( 99 )   Knowledge map   Save
    FLNG (Floating Liquefied Natural Gas) is a new offshore floating production system that liquefies, stores, and unloads Liquefied Natural Gas (LNG). Helical framework cryogenic pipe is one piece of the most important equipment in the system. However, the structure of the helical framework cryogenic pipe is complex. There are a lot of nonlinear problems such as contact and friction between structural layers. As a result, it is quite difficult for theoretical modeling and numerical analysis. The obvious one-dimensional periodicity of helical framework cryogenic pipe is focused on in this paper. Based on the Novel Implementation of Homogenization method (NIAH), the microcell model of helical framework cryogenic pipe is established and the periodic boundary conditions are applied to solve the equivalent mechanical properties of the macro structure. The equivalent method based on NIAH is validated by comparing with the calculated results of fine finite element model. It is found that the relative error is within 3.60% and the calculation cost is reduced by 32 times approximately. In addition, for the structure characteristics of spiral wound hose, a new method of applying double symmetric boundary conditions is proposed, which reduces the error by 78.00%, compared with the traditional single symmetric boundary conditions. Finally, the different equivalent stiffness results based on different periodic boundary conditions are compared and the structural characteristics of the different periodic boundary conditions are summarized. It provides a reliable and fast equivalent calculation method for structure design and analysis of the helical framework cryogenic pipe.
  • Anti-penetration performance of graphene oxide/ceramic ball reinforced polyurethane SPS composite plate
    ZOU Guangping1, WU Songyang1, YANG Liu2, CHANG Zhongliang1, WANG Xuan1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 17-24.
    Abstract ( 262 ) Download PDF ( 171 )   Knowledge map   Save
    The addition of inorganic filler can greatly enhance the performance of polyurethane, so that the performance of the composite structure with polyurethane as the core layer can be improved. In order to obtain SPS composite plates with better penetration resistance, graphene oxide reinforced polyurethane elastomers were obtained by in-situ polymerization and tested under uniaxial tension and compression. On this basis, ceramic balls were added as a new reinforcing phase, and SPS composite structures with graphene reinforced polyurethane and graphene / ceramic balls reinforced polyurethane as the core layer were prepared with Q235 steel as the panel, Through the penetration experiment of steel ball projectile and LS-DYNA numerical simulation, the ballistic limit velocities of the two composite plates are obtained, and their energy absorption characteristics and damage mechanism are analyzed. The results show that when the mass fraction of graphene is 0.4wt%, the compressive modulus of graphene reinforced polyurethane is increased by 32.4% and the tensile strength is increased by 42.6% compared with pure polyurethane. After adding ceramic balls, the ballistic limit velocity of the composite plate increased by 20.8%. The fragmentation and offset of ceramic balls interrupted the propagation of radial stress, and the ceramic balls beyond the size of bullets were relatively complete.
  • Nonlinear fuzzy MPC control for vehicles under extreme conditions
    SUN Chuanbin1,2, DENG Shuchao1, YIN Guodong2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 25-35.
    Abstract ( 417 ) Download PDF ( 97 )   Knowledge map   Save
    Aiming at yaw stability and roll stability of vehicle under emergency steering, nonlinear model predictive (MPC) integrated control of active front wheel steering (AFS) and direct yaw moment (DYC) was studied. Considering nonlinear variation of vehicle lateral stiffness, four linear yaw- roll subsystems of vehicle were established with Takagi-Sugeon theory (T-S), and dynamic parameters of tire were obtained with fuzzy observer in real time. In order to eliminate yaw stability constraint, an improved yaw ideal reference model was established under T-S framework, and a yaw stability index was introduced to constrain ideal yaw motion. Building optimal target in infinite prediction time domain with quadratic evaluation function of tracking deviation for yaw angular velocity, side-slip Angle, as roll motion and control input, model predictive fuzzy controller (MPC-TS) was designed based on distributed compensation scheme, with driver steering inputs as disturbance, and adaptive active steering constraints according to cornering characteristics. The nonlinear MPC control in infinite time domain was transformed into a convex optimization process with LMIS, and linear inequality of minimum value problem was derived under steering disturbance. Finally, simulation test was carried out with Trucksim-Simulink software, with Sine with Dwell curve and Fishhook curve as driver inputs to simulate emergency steering. Results show that despite in strongly nonlinear process under emergency steering disturbance, MPC-TS controller enhances yaw - roll stability of vehicle on both low adhesion and high adhesion road friction.
  • Vibration prediction of oil and gas pipeline plugging robot in plugging process
    MIAO Xingyuan, ZHAO Hong
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 36-49.
    Abstract ( 231 ) Download PDF ( 77 )   Knowledge map   Save
    Pipeline maintenance technology based on the pipeline isolation plugging robot (PIPR) is an important means to ensure the safe transportation of pipelines. Aiming at the shock vibration of PIPR during plugging operation, the vibration analysis was carried out from two aspects of motion process and plugging operation. The PIPR’s dynamic model based on fluid-solid coupling was established to analyze the axial, radial and pitch vibrations of the PIPR during the movement. The plugging experiment for different spoiler models of PIPR was carried out to observe the change of flow field during the plugging process. And the pressure gradient during the plugging process was used to measure the vibration of PIPR. The Kernel Extreme Learning Machine (KELM) optimized by Improved Seagull Optimization Algorithm (ISOA) was proposed to establish the pressure gradient proxy model for each spoiler model respectively, to realize the vibration prediction of PIPR. The results showed that the proposed proxy models could achieve accurate prediction of pressure gradient during the plugging process for different spoiler models. This had guiding significance for ensuring the stability of the plugging operation.
  • Oscillation criteria of second order Emden-Fowler time-delay differential equations with a sub-linear neutral term
    ZENG Yunhui1, LUO Huihui2, WANG Yilin1, LUO Liping1, YU Yuanhong3
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 50-57.
    Abstract ( 217 ) Download PDF ( 146 )   Knowledge map   Save
    The paper is devoted to the study of oscillation of solutions to second-order Emden-Fowler delay differential equations containing a sub-linear neutral term of the form  where  are quotient of odd positive integers, and  By using the Riccati substitution , integral averaging and inequality techniques, three new oscillation criteria for the equation are established. which extend classical Leighton and Kneser  oscillation criteria to super-linear Emden-Fowler delay differential equation. And, we not only extend but also improve several results about the cases of   or in the literature, recently. The effectiveness of the obtained criteria are illustrated via examples.
  • Effects of crossflow thermal buoyancy on flow-induced vibration of side-by-side cylinders
    YU Huafeng1,2, SUN Zhenzhou1,2, WANG Yixuan3, JI Chunning1,3
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 58-65.
    Abstract ( 180 ) Download PDF ( 104 )   Knowledge map   Save
    In this paper, the flow-induced vibration of two side-by-side cylinders under the action of cross-flow thermal buoyancy is numerically simulated by using the immersed boundary method. The maximum vibration amplitude, time-mean displacement, lift and drag coefficients, frequency characteristics and the wake patterns of the cylinders varying with the spacing ratio and the reduced velocity are studied in detail with the Richardson number of Ri = 3. It is found that the amplitude, lift and drag coefficients of the side-by-side cylinders are non-identical under the action of thermal buoyancy. Besides the vortex-induced vibration, galloping appears at higher reduced velocities. The balanced position of the cylinders is inversely offset with regard to the direction of the thermal buoyancy, relative to its initial position, and the offset increases with the increase of reduced velocity. In the vortex-induced vibration, the wake shows the stable wide-narrow pattern, with the vortex shedding of the two cylinders being anti-phase synchronized. In the galloping, the wake displays the in-phase synchronized pattern while the vibration response of the cylinders shows the superharmonic lock-in phenomenon.
  • Dynamic characteristics analysis and optimization of safety valve based on improved NSGA-Ⅱ algorithm
    LI Shuxun1,2, LIAN Chao1,2, PAN Weiliang3, HOU Jianjun1,2, WANG Zhihui1,2, LIU Jinwei1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 66-74.
    Abstract ( 208 ) Download PDF ( 114 )   Knowledge map   Save
    Aiming at the lack of high-precision prediction models and optimization methods for the dynamic performance of safety valves, a dynamic response system model considering damping factors and gas diffusion factors and an optimization method based on the improved NSGA-Ⅱ algorithm are proposed. The simulation model is established through the dynamic response system model of the safety valve, and the dynamic characteristics of the opening and closing process of the safety valve are simulated. Compared with the dynamic characteristics test results, the accuracy of the dynamic response system model is verified; a weight vector setting is introduced into the NSGA-II algorithm. method and self-adaptive mutation operator for multi-objective optimization of safety valve structural parameters. After optimization, the response time, vibration amplitude and stability value of the evaluation indexes of the dynamic characteristics of the safety valve are shortened by 5.95%, 68.29% and 1.98% respectively compared with those before optimization. The results show that the optimization method can improve the dynamic performance of the safety valve.
  • Viscous-adhesive motion transition mechanism of vibration system with collision and friction
    WU Shaopei, HE Bo, LI Guofang, LI Deyang, DING Wangcai
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 75-81.
    Abstract ( 258 ) Download PDF ( 137 )   Knowledge map   Save
    Aiming at a single-degree-of-freedom vibration system with friction and impact, the periodic motion of the four different types of motions including free sliding, collision, adhesion and viscous in the phase space is analyzed . Identify and study the distribution of periodic motion of the system in the parameter domain combined with four different Poincaré mapping sections. Using the parameter continuation algorithm and the cell mapping algorithm, combined with the system stability judgment conditions, the system's periodic viscous-adhesive motion distribution and transition law are revealed. The research results show that the periodic viscous-adhesive motion is mainly concentrated in the low-frequency small gap area. During the transition of the system to the periodic viscous-adhesive motion, the number of collisions increases and the collision speed gradually decreases under the induction of the grazing bifurcation (GR). At the same time, the periodic band of periodic motion gradually narrows. The transition process of adjacent periodic motions is mainly induced by rubbing bifurcation (GR), saddle knot bifurcation (SN) and sliding bifurcation (SL). Due to the mutual irreversibility of transitions, GR-SN and (GR- SL)-SN and other different forms of polymorphic coexistence areas. The system gap and recovery coefficient are reduced, the viscous-adhesive movement frequency band becomes wider, and the starting point extends in the direction of high frequency.
  • Effects of trapezoidal cutting at blade outlet on flow-induced noise of centrifugal pump volute
    GUO Rong1,2, LI Xiaobing1, LIU Xiang1, LI Tianpeng1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 82-91.
    Abstract ( 228 ) Download PDF ( 83 )   Knowledge map   Save
    In order to explore the influence of trapezoidal cutting at the blade outlet on the flow induced noise of centrifugal pump volute, a single-stage single suction centrifugal pump with specific speed of 66 was taken as the object, the cutting width coefficient and radial height coefficient were defined δ and γ,nine cutting schemes were designed. Based on RNG k-ε turbulence model, the three-dimensional unsteady numerical simulation of centrifugal pump was carried out. On this basis, the boundary element method (BEM) was used to calculate the internal field noise, and the structural finite element (FEM) coupled acoustic boundary element method was used to calculate the external field flow induced noise. The hydraulic characteristics and noise radiation characteristics of centrifugal pump under different cutting schemes were analyzed, and the accuracy of numerical calculation was verified by experimental method. The research shows that the rotor-stator interaction was the main cause of the flow induced noise of the volute of the centrifugal pump. The reasonable trapezoidal cutting of the blade outlet can basically stabilize the hydraulic performance of the centrifugal pump and effectively reduce the rotor-stator interaction intensity and the flow induced noise level of the volute. The sound pressure level at the inlet and outlet monitoring points at the blade frequency decreased by 13% and 7.5% respectively, and the sound pressure level at the field noise monitoring points decreased by 2.4%.
  • Numerical investigation of transverse anti-impact performance of API 5L X56 pipe-in-pipe
    GAO Xudong1, SHI Jian1, SHAO Yongbo2, LI Kangshuai2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 92-102.
    Abstract ( 216 ) Download PDF ( 65 )   Knowledge map   Save
    With the vigorous development of the offshore oil industry, the exploitation of oil and gas fields is gradually moving into the deep sea, and the requirements for the performance of submarine pipelines are also continuously improved. Pipe-in-pipe has good thermal insulation properties and is gradually being used. To systematically study the lateral impact resistance of the pipe-in-pipe, a numerical model was established using a nonlinear finite element code and verified with experimental data. The parametric study found that under certain impact energy, the energy absorbed by the polyurethane foam accounts for a smaller proportion than the sum of the energy absorbed by the inner tube and the outer tube of pipe-in-pipe. With the increase of the wall thickness and the steel grade of the pipe-in-pipe, the degree of local indentation of the pipe decreases, and the ability of submarine pipe-in-pipes to resist impact deformation is stronger. As the overhang length of the pipe-in-pipe increases, the residual displacement of the mid-span section of the pipe-in-pipe gradually increases, while the residual deformation of the cross-section and the depth of local indentation gradually decrease, and the proportion of the global bending deformation increases gradually, while the proportion of local indentation decreases.
  • Structural contact-collision behavior analysis based on bar system discrete element method
    XU Qiang1,2, YE Jihong1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 103-110.
    Abstract ( 311 ) Download PDF ( 176 )   Knowledge map   Save
    This paper presents the structural connect-impact analysis using the member discrete element method(MDEM), and the collision response between the members is simulated by correcting the particle motion trajectory. Firstly, a point-line contact model is established based on the possible contact modes between the members, and then the concept of virtual contact point pairs is introduced into the critical contact constraint conditions, also, the formulations of the contact force are deduced in detail. The program based on the MDEM is also develop by Fortran Language to analyze structural contact-impact behaviors. The correctness and effectiveness of the algorithm are quantitatively verified through the simulation and analysis of typical numerical examples. The results show that the point-line contact model can make timely judgments on contact-impact between members and accurately calculate the normal repulsive force and tangential friction force, meanwhile, there is energy dissipation in the process of contact-impact.
  • Effects of strength ratio on energy dissipation of quasi-composite rock samples under impact load
    WEN Sen1,2, WU Fei1, LI Sheng1, SHENG Guilin1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 111-118.
    Abstract ( 220 ) Download PDF ( 221 )   Knowledge map   Save
    The dynamic impact test of composite rock samples was carried out by using the split Hopkinson pressure bar test device with a diameter of 50 mm. The effects of different strain rates, different incident sequences of incident waves, different strength ratios and different incident angles on the energy dissipation of rock mass were studied. The test results show that the incident energy, absorption energy and energy utilization rate of composite rock samples increase with the increase of strain rate. Different incident order has different influence on absorption energy and energy utilization rate, and with the increase of intensity ratio, the influence of different incident order decreases gradually. When the strain rate is about 270s−1, the energy utilization rates of composite rocks samples with different strength ratios decrease first and then increase with the increase of incident angle. When the incident angle is 30°, the energy utilization rate is the smallest, and when the incident angle is 90°, the energy utilization rate is the largest.
  • Non-destructive testing method of anchor rod axial force based on vibration response characteristics of anchor rod components
    WANG Yusai1, ZHANG Kai2, XIAO Fangyuan1, CAO Heng1, ZHANG Mengyu1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 119-126.
    Abstract ( 268 ) Download PDF ( 99 )   Knowledge map   Save
    Measuring the anchor rod's axial force helps determine surrounding rock stability. The relationship model between bolt vibration frequency and axial force was constructed based on contact mechanics theory, and a vibration test of the anchor anchoring system was conducted. By collecting vibration signals from nuts and pallets, bolts and pallets' nonlinear vibration properties under various force conditions were analyzed, and a relationship between their vibration frequencies and axial forces was obtained; a real-time nondestructive testing (NDT) method for axial force was proposed based on the bolts and pallet's nonlinear vibration. The test results show that nut and pallet vibration frequency increases non-linearly with increasing anchor axial force, nut's frequency is not lower than pallet's, and pallet's growth rate is higher than nut; the growth of both vibration frequency and axial force is a single-value mapping connection, and nut and pallet vibration can be used to detect anchor axial force non-destructively.
  • A method of DOA estimation of acoustic vector sensor array based on sparse reconstruction under non-uniform noise
    WANG Weidong1, LI Xiangshui1, LI Hui1, SHI Wentao2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 127-136.
    Abstract ( 238 ) Download PDF ( 107 )   Knowledge map   Save
    To improve the direction of arrival (DOA) estimation performance of the acoustic vector sensor array in the presence of non-uniform noise, the sparse signal reconstruction methods based on weighted least squares (WLS) and weighted covariance matrix fitting (WCMF) are proposed in this paper. Firstly, a virtual manifold matrix of acoustic vector sensor array is defined, and the covariance matrix containing the sparse signal power and the noise power is reconstructed. To estimate the sparse signal power and the output noise power of each channel for the acoustic vector sensor array, a cost function via the sparse signal power and the noise power is then formulated based on the WLS method and the sparse signal weighted minimization method. On this basis, to further improve the estimation accuracy of sparse signal power and noise power, the formulated cost function is improved based on the WCMF criterion. Finally, the nonlinear cost function is transformed into a linear function by using the Taylor series expansion, then the sparse signal power and the noise power are estimated by loop iterative algorithm. Furthermore, the spectral peak search is performed on the sparse signal power to achieve the DOA estimation of sources when the iteration is terminated. Simulation results show that the proposed methods achieve a more accurate DOA estimation compared to the existing non-uniform noise power estimation methods.
  • Single-channel de-correlation, separation and correction of train bearing fault sound signals
    ZHAO Xinhang1, LIU Fang1,2, HUANG Mingtao1, ZHU Zihao1, HOU Chaoqiang1, LIU Yongbin1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 137-146.
    Abstract ( 405 ) Download PDF ( 56 )   Knowledge map   Save
    A single channel de-correlation source separation time-domain interpolation resampling method (SCDBSS-TIR) is proposed for the wheel-track contact noise interference and Doppler aberration problems in track-side acoustic detection system. A single microphone directly opposite the wheelset bearing is used to acquire noisy single-channel observation signals, which are firstly converted into two-channel observation signals using singular spectrum analysis; then multiple time-delay correlation matrix eigenvalue decomposition is used for sound source separation; finally, Doppler aberration correction is performed using the time-domain interpolation resampling method. Simulations and experiments show that the proposed method outperforms the classical determined blind source separation method under the influence of Doppler effect, and also has a good effect on in-band noise cancellation. It is expected to be applied in TADS.
  • Effects of large cantilever on seismic response of transfer-cleaning room structure in nuclear power plant
    LI Xiaojun1， LIU Xuchen1,2， WANG Xiaohui3， WANG Yushi1， HE Qiumei3， WANG Ning3
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 147-154.
    Abstract ( 153 ) Download PDF ( 69 )   Knowledge map   Save
    Based on the prototype of transfer and purging rooms in nuclear power plants, the finite element models of transfer and purging rooms without a cantilever and with a cantilever were established. Based on the modal analysis and dynamic time history analysis of the two models, the influence of the cantilever on the seismic performance of the transfer and purging rooms was analyzed, and the dynamic characteristics and seismic performance of the transfer and purging rooms were discussed. The results show that the structural stiffness of the transfer and purging rooms is great, the natural vibration period is short, the seismic response is small under the excitation of ground motions beyond the design standard, and the whole structure is still in an elastic state. The large cantilever in the structure obviously reduces the stiffness of the transfer and purging rooms, prolongs the natural vibration period of the structure, and increases the overall seismic response of the structure, but the amplification is not significant. And the transfer and purging rooms with a cantilever fully meet the requirements of seismic performance.
  • Damage recognition and safety evaluation of retaining wall structure under environmental excitation
    XU Qian
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 155-162.
    Abstract ( 183 ) Download PDF ( 48 )   Knowledge map   Save
    The damages will appear within retaining wall structures in service under many factors, the damage may decrease the safety of retaining wall structures. To evaluate the safety of retaining wall structures in service, the Hilbert marginal energy ratio spectrum analysis was performed via the Hilbert-Huang Transformation of a virtual impulse response function of responses to the retaining wall structure under ambient excitation. Based on the damage sensitivity analysis of bands obtained via the Hilbert-Huang Transform, the Hilbert damage feature vector and damage index, which were used to reflected damage information of the retaining wall, were created. Tests on a pile plate retaining wall structure in service were performed. The vibration caused by vehicles was regarded as excitations. Multiple field tests on the retaining wall were performed under ambient excitations with considering the influences of environmental temperature and humidity. The damage index was used to identify the damage within the retaining wall and evaluate the safety of the wall. The tests results indicate that the value of the damage index increases continuously and the safety of the wall decreases under the persistent effects of ambient excitations. It is shown that damages appear within the wall continuously, the damage intensity of the wall increases continuously, and the stability of the wall decreases gradually. The safety of the can be evaluated via establishing quantitative relationship between the stability coefficient and damage index. In addition, the temperature and humidity have larger influences on damage accumulation. Especially, high temperature and heavy rainfall will accelerate appearance of the damage within the retaining wall. Thus, the damage index can be used to identify damages within the wall and evaluate the safety of the wall.
  • Multi-objective optimization design of new median guardrail
    LU Jijian, LEI Zhengbao
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 163-169.
    Abstract ( 216 ) Download PDF ( 75 )   Knowledge map   Save
    In view of the tire snagging phenomenon of the widely used median guardrail, a new median guardrail is designed. The crash safety of the new median guardrail is evaluated by explicit nonlinear finite element simulation. The dynamic responses of the barrier after collision, such as occupant impact velocity (v), occupant impact velocity (a), exit angle (EA), vehicle departure distance (d) and maximum lateral displacement (MD), are analyzed. Considering comprehensively, the acceleration in y direction of occupant impact (a_y) and vehicle departure distance (d) are selected as the objective functions, and the RBF surrogate model is constructed to reduce the calculation cost. Finally, multi-objective genetic algorithm is used to optimize and obtain the best design parameters of guardrail. Under the impact of small bus, medium bus and large truck, the new median guardrail shows good guidance ability. The finite element simulation results show that the guardrail can effectively prevent the tire snagging phenomenon, the departure distance only 2.06m, and the acceleration in the y direction of occupant collision is 118.2 m/s2, meeting the SB level protection requirements.
  • Free transverse vibration of composite laminated beam restrained by torsion springs
    CHEN Qingyuan, LI Jing, FANG Pengya, PEI Shixun, LIU Shuangyan, SU Yi
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 170-176.
    Abstract ( 239 ) Download PDF ( 586 )   Knowledge map   Save
    Based on the Galerkin method, an explicit analytical solution for free vibration of laminated composite beams with the boundary ends elastically-restrained against rotation is presented. In order to avoid the numerical instability of the classical vibration eigenfunction of higher order (≥11) modes, the transverse deflection functions of the rotationally-restrained laminated composite beams are constructed through a unique weighting combination of (modified) vibration eigenfunctions of hinged-hinged, fixed-fixed, hinged-fixed and fixed-hinged beams. The validity study shows that the present explicit analytical solution is effective in performing free vibration analyses of laminated composite beams with ends elastically-restrained against rotation.
  • Dynamic calibration method of digital angular vibration sensor based on machine vision
    LIU Wenfeng1, YANG Ming1, CAI Chenguang2, LIU Zhihua2, YANG Jing1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 177-182.
    Abstract ( 440 ) Download PDF ( 65 )   Knowledge map   Save
    Low-frequency angular vibration sensors are widely used in the applications of inertial navigation, attitude estimation, precision control, and their sensitivity calibration accuracy are the key to determine the performance of these applications. At present, the most commonly used calibration methods are the laser interferometry and circular grating method. However, the former usually needs an expensive and complex system, and the latter only has the limited calibration frequency range and application scope, they are difficult to meet the increasing calibration demand of high-performance angular vibration sensors. The machine vision method with sub-pixel edge extraction accuracy is adopted to accurately measure the input angular excitation of low-frequency angular vibration sensors so as to achieve the reliable sensitivity calibration in a wide low-frequency range, which can ensure the accuracy and efficiency simultaneously. Compared with the laser interferometry and circular grating method, the machine vision has the similar calibration results with the laser interferometry and circular grating method in the range of 0.01-5 Hz, and their maximum relative deviations are about 0.6% and 0.4%, respectively. In addition, the maximum relative standard deviation of the calibrated sensitivity by the machine vision method in this whole range is about 0.5%.
  • Mechanical properties of star-shaped auxetic honeycomb material under compression-shear composite loading
    LUO Geng1,2, MO Duanyu1, LIU Junzhe1, CHAI Chengpeng1, CHEN Yisong1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 183-192.
    Abstract ( 223 ) Download PDF ( 79 )   Knowledge map   Save
    Auxetic honeycomb materials are widely used in various protective structures due to their good mechanical properties and stable energy absorption properties. In this paper, the finite element technology is used to establish the numerical model of the star auxetic honeycomb material, and the verification experiment is carried out based on the additive manufacturing technology and the universal testing machine. Furthermore, the simulation investigation of star-shaped auxetic honeycomb material under different compression-shear composite loading angles and speeds was carried out, and the yield surface of star-shaped auxetic honeycomb material was established. The results show that the star-shaped auxetic honeycomb material undergoes overall deformation under low-speed composite loading relying on the rotation of the cells, and produces oblique deformation belt crushing. More fully, the material deformation mode changes from overall deformation to local deformation, forming stress waves. The initial yield stress of the material was fitted by the ellipse equation, and the yield surface of the star-shaped auxetic honeycomb material was established. With the increase of the speed, the initial yield surface of the material showed obvious strengthening. The total energy absorption in the tangential and tangential directions showed a decreasing and increasing trend, respectively, and the tangential energy absorption characteristics were more sensitive to the change of the angle than the normal direction.
  • Dynamic response of beam on Winkler foundation with finite depth under moving load
    WANG Ju1, MA Jianjun1, 2, HAN Shujuan1, LI Da1, GUO Ying2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 193-198.
    Abstract ( 252 ) Download PDF ( 93 )   Knowledge map   Save
    Based on the theory of beam on Winkler foundation considering finite depth soil mass motions, the lateral motion equation of the finite-length beam on elastic foundation subjected to moving load is derived. The modal superposition method is used to obtain the analytical solution of the dynamic response of the finite-length beam subjected to the moving load. The separation variable method is used to get the first-order approximate answer of the finite-length beam vibration after the moving load. Using the numerical calculation and parameter analysis, the dynamic characteristics of beams with simply supported boundary conditions on the Winkler foundation with finite depth subjected to moving load are revealed. The effects of the mass of the foundation, the viscous damping coefficient of the foundation, and the moving speed of load on the dynamic response of the finite length beam in the forced vibration stage and the free vibration stage are analyzed, and it fully reveals the effect of the soil movement on the critical velocity. The results show that the depth of the foundation significantly reduces the critical speed; Moreover, the viscous damping of the elastic foundation significantly prolongs the decay time of the free vibration; the moving speed of the load intensifies the interaction effect between the finite depth elastic foundation and its supporting beam, the amplitude and response period of the system vibration are significantly changed.
  • Denoising of rolling bearing vibration signals based on CEEMDAN-IAWT method
    REN Haijun, WEI Chong, TAN Zhiqiang, LUO Liang, DING Xianfei
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 199-207.
    Abstract ( ) Download PDF ( 119 )   Knowledge map   Save
    To solve the problem of mixing noise into rolling bearing vibration signals, a joint noise reduction method is designed, which combines the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and the improved adaptive wavelet threshold (IAWT). First, use CEEMDAN to modal decomposition of the signal to obtain intrinsic mode functions (IMFs); Then the obtained IMFs and the original signal were analyzed to identify the effective component. Aiming at the problem that wavelet threshold denoising algorithm(WT) can not adaptively select wavelet base and decomposition layer and threshold function has defects, IAWT algorithm is designed, IAWT algorithm is used to filter noise in IMFs. Finally, the processed IMFs signal is reconstructed. The designed joint denoising algorithm is used to process simulation signals and experimental signals. Compared with WT, the signal-to-noise ratio of the signal processed by IAWT is improved by about 0.5dB, the correlation coefficient with the original signal is increased by about 0.03, and the root mean square error is reduced by about 0.01. By comparing the proposed method with CEEMDAN-WT and other methods, the signal-to-noise ratio of signal processed by the proposed method is improved by at least 1.37dB, and the signal characteristics are well preserved.
  • Mechanical properties of molecular spring vibration isolator based on metal organic skeleton material
    JIN Yang, CHEN Weidong, CHEN Qian, TENG Handong
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 208-213.
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    The mixture of metal organic framework material and water was placed in a closed container as the working medium to form molecular spring isolator based on metal organic framework material. When the isolator is subjected to external load, water invades and escapes from the hydrophobic micropores of the metal-organic framework material under external pressure, realizing the storage and release of energy. The process of water molecules invading micropores of metal-organic framework material was simulated by the relationship between micromechanical equilibrium and macroscopic volume change. The force displacement relationship of vibration isolator was deduced during the loading process. The mechanical model was verified by quasi-static test, The influence factors of the performance of the isolator were analyzed by simulation and experiment. The results show that the theoretical and experimental results are in good agreement, and the molecular spring isolator based on metal-organic framework material shows the characteristics of high-low-high segmental stiffness, The minimum contact angle, maximum pore diameter, cobalt ratio and pore volume of the metal organic framework material will have an impact on the stage II of the vibration isolator. Adjusting these parameters can flexibly adjust the performance of the vibration isolator.
  • Prediction of bearing performance degradation trend based on CAE and TCN
    LIU Yuanbo, CHEN Xiang, LIU Yu
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 214-225.
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    Aiming at the shortcomings of existing performance degradation prediction research, such as information loss when building health indicator, poor parallel computing performance and small receptive field when building prediction models, combined with the timing characteristics of performance degradation of monitored objects, a performance degradation prediction method based on Convolutional Auto-Encoder (CAE) and Temporal Convolutional Network (TCN) is proposed. Firstly, construct a high-dimensional feature set in the multi-domain of vibration signals, and use comprehensive evaluation indicators to preliminarily screen performance degradation indicators with good sensitivity and strong trend. Secondly, the Kernel Principal Component Analysis (KPCA) method is adopted to eliminate redundant information between multi-domain features and realize the construction of health indicator based on CAE network. On this basis, a performance degradation prediction model based on TCN is constructed, and direct multi-step prediction is used to achieve performance degradation trend prediction, and the effectiveness of the method is verified by using the bearing public data set. The results show that the feature set can be reduced from 14 dimensions to 4 dimensions by using KPCA, while 97.63% of the information of the original feature set is retained. Furthermore, the method of constructing health indicator based on CAE network is effective. The change process of the constructed health indicator truly reflects the performance degradation process of the bearing. Compared with the two commonly used health index construction methods, Auto-Encoding (AE) network and Gaussian Mixture Model (GMM), this method has obvious advantages. At the same time, the prediction model based on the TCN algorithm can accurately predict the performance degradation of the bearing, which has better performance and higher prediction accuracy than the prediction model based on the Long Short-Term Memory (LSTM) network and the Gated Recurrent Unit (GRU). The root mean square error and mean absolute error when the prediction step size is 3 are 0.0257 and 0.0187, respectively. This method has general significance and may be extended to predict the performance degradation trend of other mechanical equipment/components.
  • Fault diagnosis of water supply pump in industrial circulating water system based on DTCNN-SVM
    WU Jia, LI Mingchen, TANG Wenyan
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 226-234.
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    The working state of the water supply pump in the industrial circulating water system is an important factor affecting the safe production of the industrial process. In order to identify the working state of the water supply pump timely and accurately, a fault diagnosis method based on deep transfer convolutional neural network and support vector machine (DTCNN-SVM) was proposed. Firstly, the vibration signal which is strongly related to the working state is preprocessed to realize the two-dimensional grayscale image of the vibration time series signal. On this basis, the deep transfer convolutional neural network model which combined transfer learning and residual neural network is used to extract the grayscale image features of the vibration signal, and the deep learning features are reduced based on the fuzzy inconsistency measurement. Finally, the support vector machine method is used to establish the fault diagnosis model of water supply pump. The experimental results show that the proposed method can effectively identify the working state of the water supply pump with a small amount of sample data and model parameters.
  • Vulnerability and probabilistic seismic loss of highway tunnel considering two parameters
    SU Qi, FAN Jin
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 235-241.
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    The research on the fragility analysis and probabilistic seismic economic loss of highway tunnel based on double intensity measures is significant for pre-earthquake earthquake prevention and post-earthquake emergency repair. In this paper, the evaluation framework of probabilistic seismic economic loss in the whole life cycle of highway tunnel is established, the double intensity measures are introduced, the fragility analysis is carried out by incremental dynamic analysis method. The comparison between the analytical fragility surface and the empirical fragility curve verifies the rationality of the model and the fragility surface established in this paper. On this basis, the probabilistic seismic economic losses in the whole life cycle of tunnel are evaluated. The results show that the fragility surface based on double intensity measures can reflect the structural damage more accurately, and the probabilistic economic loss caused by slight damage is the largest during the whole life cycle of highway tunnel, followed by moderate damage. The framework of tunnel probabilistic seismic economic loss assessment proposed in this paper can provide reference for highway tunnel seismic economic loss assessment.
  • Test study on vibration behavior and bearing load characteristics of high-speed train gearbox under internal excitation
    ZHOU Yue1, WANG Xi1, HOU Yu1, QUE Hongbo1,2, GUO Rubing2, LIN Xinhai2,JIN Siqin2, WU Chengpan2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 242-250.
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    Internal excitation is an important factor affecting the vibration of high-speed EMU gearbox and the dynamic load of gearbox bearing. Based on the gearbox transmission system test rig, the vibration response of the gearbox body and the bearing load of the gearbox were tested under various torque and speed conditions for high-speed EMU. The vibration signals of different parts of the gearbox under various operating conditions are analyzed, and it is found that the gear meshing frequency at specific rotation speeds can excite the modal resonance of the gearbox, while the torque can affect the frequency response characteristics of the system. Order tracking are performed on the gearbox vibration acceleration responses under increased rotation speed, and modal parameters of the gearbox are obtained through the order-based operational modal identification method, it is found that the operating mode vibration pattern of the gearbox cause the difference in vibration behavior at different rotation speeds. By comparing the root mean square of gearbox vibration acceleration and the measured bearing load coefficient of variation under different operating conditions, the correspondence between the dynamic characteristics of gearbox bearing load and gearbox vibration behavior is established.
  • Tests and numerical analysis for effects of polyurea coating on anti-knock performance of armor steel plate
    HE Jiahao1, WU Mengyang1, LI Gaowei1, SHI Wen2, SUN Xiaowang1, WANG Xianhui1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 251-258.
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    In order to study the influence of polyurea coating spraying position and coating thickness on the explosion resistance of steel plate, 2 kg TNT explosive explosion tests were carried out on four different types of spraying structures and pure steel plate structures, and the test conditions were numerically simulated by LS-DYNA simulation software. The reliability of numerical calculation was verified by comparing the test results. At the same time, the stress wave attenuation characteristics in the front and back spraying structures were calculated and analyzed theoretically. On this basis, the influence of coating thickness on the explosion resistance of back sprayed structure is further studied. The results show that compared with the non-spraying, face-to-face and double-sided spraying structures, the back spraying shows more significant explosion resistance potential, and the large impedance ratio structure formed by it is an important reason for the effective attenuation of the peak value of stress wave; Under the condition of equal steel plate thickness, increasing the coating thickness can effectively improve the structural resistance, but the degree of improvement decreases with the increase of polyurea / steel plate thickness ratio; Under the condition of equal surface density, increasing the thickness of the coating will aggravate the damage of the structure.
  • Dynamic optimization of two-stage reducer considering design and layout parameters
    JIN Pengcheng, ZHOU Jianxing, QI Le, WANG Shengnan, ZHOU Hengyu, SONG Lirui
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 259-268.
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    In order to study the dynamic performance optimization method of multistage fixed-axle gear train,a parametric dynamics model including gear design parameters (number of teeth,modulus,tooth width) and system layout parameters (gear installation position,interstage phase Angle) was established by using the generalized finite element method. Newmark-β time domain integral method was used to solve the dynamic equation at rated speed,and the influence of each parameter on the dynamic characteristics of the system was analyzed. On this basis,the multistage fixed axis gear system dynamic optimization method is proposed,taking design and layout parameters as variables,reducer gear ratio,the diameter of axle width as constraint conditions,such as dynamic load amplitude and minimum on bearing load difference as the main target,multi-objective hybrid discrete optimization model is established, and obtain the optimal design variables based on bayesian algorithm programming model. The results show that the amplitude of the first stage meshing force of the optimized reducer is reduced by 18.9%,the amplitude of the second stage meshing force is reduced by 17.2%,and the load difference of bearings on both sides of shafting is reduced by 36%,40% and 45% respectively. The mass decrease by 8.7%,the volume of boundary box decrease by 27%,and the optimization effect is obvious.
  • Longitudinal-transverse-torsional coupled nonlinear vibration model of drill string in deepwater riser-free drilling
    LIU Jun1,2, LIANG Shuang1, CAI Mengqi2, CHEN Yili1, YUAN Mingjian1, ZENG Linlin1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 269-277.
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    Riserless drilling is a promising deepwater drilling technology. In view of the fact that there is no effective dynamic analysis model for deepwater riserless drilling, taking into account the displacement of the drilling ship, wind and ocean current, tidal current, wave load, wellbore contact, bit-rock interaction and seawater formation interaction, a longitudinal- lateral -torsional coupling nonlinear vibration model of the whole drillstring system of deepwater riserless drilling is established, through the energy method, micro element method and Hamilton principle. The governing equations are discretized by Lagrange and cubic Hermite function, and are solved numerically by Newmark-β method. Using the existing marine riser simulation experimental data, Moharrami’s torsional vibration model results and Kyllingstad’s field test data, the model is compared and verified in detail from the qualitative and quantitative point of view. The results show that the model has good accuracy and can be used for the coupling vibration analysis of deepwater riserless drill string.
  • Diesel engine fault data augmentation method based on artificial data fusion
    HUANG Meng1, BI Xiaoyang2, YANG Xiao1, LI Xin1, TANG Daijie1, BI Fengrong1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 278-286.
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    Aiming at the problems of over-fitting and low accuracy of the data-driven diesel engine fault diagnosis method caused by the lack of data, a data augmentation method based on artificial data fusion was proposed to augment the training set. This method introduced the Wasserstein distance and gradient penalty into the auxiliary classifier generative adversarial network (ACGAN) in order to overcome the training instability of the original ACGAN. Two kinds of artificial data generated by the ACGANs before and after optimization were introduced into the original training set in proportion, and the training set was augmented from two perspectives: enhancement of the original data and optimization of the judgment range of diagnostic network. The analysis results of the measured vibration signals of the diesel engine show that the diagnosis accuracy under different fault types is improved by this data augmentation method, and the optimization effect is better than the other comparison method in this article.  
  • Random vibration damage and fatigue life prediction of automobile logistics equipment
    QI Chang1,2， GAO Jian1,2， MIAO Tingting3
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 287-295.
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    Auto parts products are often transported by logistics equipment in the form of stacking to avoid damage. In this paper, the random vibration experiment method is used to analyze the vibration damage of stacking steel logistics bins under three different vibration levels. Then, based on the interaction relationship between logistics bins, load and fixture, the explicit finite element model of panoramic skylight transportation equipment is established. The fatigue response of the equipment under stationary Gaussian random vibration is studied. The deformation and equivalent stress at the key position are obtained, and the fatigue life of the equipment is predicted. The results show that the resonance frequency obtained by finite element analysis is 3.4% different from that of random vibration experiment; The vibration response of the bin is mainly affected by the low-order resonance frequency, and the maximum stress is concentrated at the connection between the stacking column and the pallet; The response acceleration of the upper load 1.42g is significantly higher than that of the lower load 0.79g, while the difference between the response acceleration of the same upper load is less than 1.7%; The response accelerations of the upper and lower stacking columns are 0.82g and 0.79g respectively, and the difference is not obvious. The above method can simulate the vibration fatigue of automobile logistics equipment and the vulnerable points of loads in the process of transportation, and can provide a certain reference for the design of automobile logistics equipment.
  • Deep learning modeling analysis method of frequency-domain data of shock wind tunnel force measurement signals
    NIE Shaojun1,2, WANG Yunpeng1,2, WANG Chun1,2, JIANG Zonglin1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 296-302.
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    High-accuracy force measurement is the key technology in shock tunnel tests. When a force test is conducted, the vibration of force measurement system is excited under the impact flow during the starting process of shock tunnel, and it cannot be attenuated rapidly during extremely short-duration (millisecond level). The balance output signal is coupled with aerodynamic force and inertial vibration. To eliminate inertial vibration, the balance signal was processed and the characteristics of dynamic samples were analyzed in frequency-domain based on deep learning. The results show that the most inertial vibration in output signal is removed and the expected results are obtained, verifying the validity and reliability of the modelling method in frequency-domain. In addition, error of processed results was analyzed, which further verifies that the modelling method in frequency-domain has great engineering application value in data processing of shock tunnel balance.
  • Attitude disturbance analysis for complex spacecraft based on variational mode decomposition
    LIN Xiaodong1,2, ZHANG Rui1,2, LIU Fang1, LAN Qing2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 303-309.
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    Attitude control system of complex spacecraft is taken as the research object. Considering the complex situation of the flexible panel and liquid storage tank of spacecraft, the characteristics of the interference torques caused by the flexible panel and liquid sloshiness in the closed loop of the attitude control system are analyzed. Firstly, the dynamic equations of the complex spacecraft were established based on the virtual power method, and the dynamics equations of the vibration and liquid sloshiness of the spacecraft were also established. Then, the phase plane control law is used to complete the closed-loop control simulation of complex spacecraft attitude, and the interference torques generated by the flexibility and liquid sloshiness are collected. Finally, based on the variational mode decomposition method, the time-frequency analysis of the time domain data of the disturbance torque is carried out to obtain its disturbance characteristics, which provides a theoretical basis for the design of the subsequent disturbance suppression algorithm. Simulation results show the applicability and accuracy of the proposed method.
  • Simulation analysis and tests of rotating damper for spacecraft deployment mechanism
    WANG Jiadeng1,2, LIU Chong3, XUE Jingsai1,2, DENG Zehua1,2, YANG Mingbo1,2, LIU Xingtian1,2
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 310-315.
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    With the increasing demand for the driving torque of large antennas of spacecraft, the problem of shock load control when the antenna is deployed in place has gradually attracted the attention of the engineering community. This paper introduces a large-stroke, large-damping rotational damper for spacecraft deployment mechanism, which can effectively suppress the impact load when the deployment mechanism is deployed. Firstly, the working principle of the rotary damper is briefly introduced, the mechanical model of the rotary damper is established, and the damping characteristics of the rotary damper are analyzed. Then, MSC.ADAMS software was used to simulate the dynamic numerical simulation of the expansion process of the antenna from the closed state to the fully expanded state, and the influence of the rotating damper on the unfolding speed and the locking impact force when it was deployed in place was analyzed. Finally, the damping performance test platform of the rotary damper was built and the damping performance test was carried out. The results show that the error between the simulated value of damping torque and the experimental value is within 2%, and the amplitude of the locking shock load decreases by 91% when the antenna is deployed in place after the rotating damper is installed, and the unfolding speed at the end of the deployment decreases by 81%, which verifies the effectiveness of the rotating damper for impact load control.
  • An active control method for profile accuracy of membrane reflector antenna
    GU Yongzhen1, DUAN Baoyan2, ZHANG Shunji2, ZHONG Wang2, ZHANG Qinggang1
    JOURNAL OF VIBRATION AND SHOCK. 2023, 42(13): 316-322.
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    Aiming at the problem of how to effectively control the shape accuracy of the membrane reflector antenna, a bidirectional control method combining with electrostatic forces and boundary cable forces is proposed. Firstly, the electrostatic forces calculation formulas are derived when the distance between the membrane reflector surface and the membrane control surface changes, and the electrostatic forces update process is given. Then, with the electrode voltages and boundary cable forces as the design variables, and the membrane reflector surface accuracy as the optimization objective, an active control model for the membrane reflector antenna surface accuracy is established. Finally, the effectiveness of the control method is verified by two simulation examples of active control of membrane reflector antenna shape accuracy under two forms of temperature load.
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