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    2024,22(9):1-15, DOI: 10.6052/1672-6553-2024-043
    Abstract:
    Structures and mechanisms in the engineering field possess characteristics such as high dimensions, nonlinearity, and strong coupling, leading to complex dynamic behaviors. In the related research field, the dimensionality reduction method is of great significance for the study of high-dimensional complex nonlinear dynamical systems. These methods can reduce the complexity of data, overcome the "curse of dimensionality" in dynamical systems, and improve computational efficiency. They can also compress and reconstruct the characteristics of high-dimensional data, extracting core characteristics to better reveal its inherent laws and features. Furthermore, they can simplify models, reduce model complexity, and improve model stability and interpretability. In recent years, the dimension reduction method system has gradually developed and improved, with many scholars utilizing them to achieve theoretical research on high-dimensional complex systems. Based on this, this paper summarizes the dimension reduction theory for nonlinear high-dimensional systems. It focuses on introducing the basic ideas, application status, and advantages and disadvantages of dimension reduction methods such as Central Manifold Theorem dimension reduction method, Lyapunov-Schmidt method, Proper Orthogonal Decomposition method (POD), and nonlinear Galerkin method. Additionally, it briefly introduces the application of other dimension reduction methods in practical problems. Finally, aiming at the problems existing in current dimension reduction methods, it proposes possible improvement plans and prospects for future research directions.
    2024,22(9):16-23, DOI: 10.6052/1672-6553-2023-111
    Abstract:
    The Herglotz-type Noether theorems for the Vacco dynamics of second-order nonholonomic systems are studied.Firstly, based on the Herglotz generalized variational principle, the Herglotz-type differential equations of motion for Vacco dynamics of second-order nonholonomic systems are established.Secondly, according to the non-isochronous variation formulas of Hamilton-Herglotz action, the concepts of Herglotz-type Noether symmetry and quasi-symmetry and their criterion equations for Vacco dynamics of second-order nonholonomic systems are given, and the Herglotz-type Noether theorems and their inverse theorems are further derived.Finally, an example is given to illustrate the application of the results.
    2024,22(9):24-28, DOI: 10.6052/1672-6553-2024-031
    Abstract:
    Korteweg-de Vries (mKdV) equation modified by two-component five-order coupled extension is proposed. By means of generalized Darboux transformation and Taylor’s expansion, obtain the iterative expression of soliton solution of the order of the equation. Discussed the real and imaginary sectors of the spectrum parameters, the free parameters are given appropriate values. The interaction graphs between solitons are drawn by numerical simulation, and the effects of different parameters on the elastic and inelastic collisions between solitons are further analyzed. The obtained results have a certain theoretical significance for the study of higher-order solitons.
    2024,22(9):29-36, DOI: 10.6052/1672-6553-2024-022
    Abstract:
    The primary resonance of Rayleigh-Duffing system with fractional time-delay feedback under parametric excitation and external excitation is studied by the averaging method. Firstly, the approximate analytical solution of the system is obtained by the averaging method, and the accuracy of the analytical solution is verified by numerical method. The amplitude-frequency equation of steady-state response is established, and the stability condition of steady-state solution is obtained based on Lyapunov stability theory. Finally, the influence of system parameters on the dynamic behavior of the system is analyzed by numerical simulation and amplitude-frequency curve. The results show that the multiple solutions caused by parametric excitation amplitude and external excitation amplitude are not the same. The effect of time-delay on the amplitude-frequency curve of the system is periodic.
    2024,22(9):37-44, DOI: 10.6052/1672-6553-2024-045
    Abstract:
    The mechanical model of super-thin elastic rod is applied to describe the nonlinear vibration behavior of the cable of long-span cable-stayed bridge.Firstly, considering the geometric nonlinearity, sag and flexural stiffness of the cable, the multimodal nonlinear vibration equation of the cable under axial excitation is derived on the basis of assuming that the static configuration of the cable is catenary.Secondly, the vibration equation is solved by multiscale method, and the existence conditions of the constant solutions of main resonance, main parameter resonance and 3:1 resonance are obtained. The sufficient conditions for the existence of the asymptotic steady solution are further obtained according to the Lyapunov’s first approximate stability criterion. Finally, the effects of frequency ratio, excitation amplitude and cable damping on cable vibration characteristics are studied by comparing the approximate solution with the numerical solution.The results show that the amplitude of the cable based on the elastic rod model is slightly larger than that of the elastic beam model, and the minimum amplitude of the main parameter resonance of the cable is reduced.Increasing damping can reduce the vibration of the cable to some extent, but the suppression effect is limited, so controlling the excitation amplitude is an effective method to reduce the vibration of the cable.
    2024,22(9):45-54, DOI: 10.6052/1672-6553-2024-029
    Abstract:
    In order to explore the partial mechanical properties of functionally graded beams under thermal conditions, the axial deformation field of functionally graded beams was established by using Gauss-Lobatoo node and Chebyshev polynomial. The discrete governing equation of the axial deformation field under thermal conditions was derived by Chebyshev spectrum method and Lagrange equation. By applying boundary conditions to the model with projection matrix method and using the comparison results of uniform Timoshenko materials for auxiliary verification, the changes of the natural frequency of the system under different temperature fields, material gradient index and anchorage conditions were analyzed. At the same time, the thermal buckling temperature of the structure was studied. The results show that under the same conditions, the natural frequencies of each order of the system decrease with the increase of temperature, and the first-order frequency decreases the most. The fourth order natural frequency decreases the least. The variation trend of natural frequency of cantilever beam is the same as that of material softening, and the decrease of the third-order frequency is more obvious than that of the first-order frequency. The natural frequencies of each order of the structure can be optimized by adjusting the material gradient index. With the increase of material gradient index, the thermal buckling temperature of the material increases continuously, but for different functionally graded materials, the thermal buckling temperature changes show different trends. This study can provide support for the research and engineering application of functionally graded materials.
    2024,22(9):55-61, DOI: 10.6052/1672-6553-2024-039
    Abstract:
    In response to the issue of violation in trajectory tracking of single leg dynamics for quadruped robots due to the incompatibility between initial conditions and constraint equations, as well as the violation caused by numerical integration on low-order constraints, a trajectory tracking control method based on the Udwadia-Kalaba method is proposed. This method utilizes the Lagrangian equation to establish unconstrained dynamic equations, considers the predetermined trajectory of the system as a constraint relationship, and establishes constraint equations based on the end position obtained from direct kinematics. Firstly, to address the problem of initial value violation, non-zero initial angular velocities of each joint are set. It is found that the trajectory tracking error based on the Udwadia-Kalaba method is relatively large. To mitigate this issue, the Baumgarte stability method is employed to reduce system errors, and a comparison with the end trajectory obtained under PID control is conducted, validating the superiority of the Baumgarte stability method in correcting initial value violations. Subsequently, considering the violation caused by numerical integration on low-order constraints, one of the constraint trajectories is set as a time-dependent linear equation. Trajectory tracking control is performed using the Udwadia-Kalaba method, which results in significant trajectory deviation. Then, the Baumgarte stability method is utilized to correct the end trajectory, achieving the goal of aligning the end trajectory with the trajectory planning.
    2024,22(9):62-71, DOI: 10.6052/1672-6553-2024-073
    Abstract:
    Because of its simple structure, high power density and good reliability, the Contact-separation mode triboelectric nanogenerator (CS-TENG) shows a good development potential in the field of ambient vibration energy harvesting. Considering the contact and collision force between the moving electrode and the fixed electrode, the piecewise-linear motion differential equation of the moving electrode is derived. Combined with the equivalent circuit differential equation of CS-TENG, an electromechanical coupling model considering the nonlinear variation of electrode spacing is established. Harmonic balance method and arc length extension technique are used to solve the dynamic output characteristics of CS-TENG and judge the stability of the system. Both numerical integration and dynamic tests are applied for verifying the accuracy of harmonic balance results. The effects of excitation amplitude, contact stiffness and structural damping parameters on the dynamic output characteristics of the system are discussed. The results are useful for the structural optimization design and practical development of CS-TENG.
    2024,22(9):72-80, DOI: 10.6052/1672-6553-2024-013
    Abstract:
    In order to deal with the problem of severe vibration of pantograph and catenary system under high-speed train operation and improve the current collection quality of pantograph-catenary, a composite controller based on model predictive control ( MPC ) and disturbance feedforward compensation is proposed to reduce the fluctuation of pantograph-catenary contact force. Firstly, based on the linearized pantograph-catenary system, a model predictive controller based on particle swarm optimization ( PSO ) is designed to optimize the fluctuation of pantograph-catenary contact force. Secondly, a generalized extended state observer ( GESO ) is constructed to estimate the unmeasurable state in the pantograph-catenary system and compensate the model uncertainty. Finally, the simulation verifies that the designed controller can effectively reduce the fluctuation of the contact force under the condition of considering the model uncertainty.
    2024,22(9):81-88, DOI: 10.6052/1672-6553-2024-046
    Abstract:
    The coupler is an important component of the heavy-haul train, and the coupler force has a significant impact on the running safety of the heavy-haul train. In order to analyse the coupler force of 20,000-ton heavy-haul train under different working conditions, based on the train longitudinal dynamics theory, train control method and the dynamic modelling method of the hook retarder, the longitudinal dynamics model of 20,000-ton heavy-haul train assembled by HXD1 locomotive and C80 coal haulage converters was established to analyse the coupler force distribution law of heavy-haul trains running though different traction force, slave control locomotive lag and different coupler clearance. The results show that: under traction conditions, The lifting speed of traction force has no obvious effect on the steady-state coupler force, while the increase of traction gear significantly increases the steady-state maximum coupler force. The traction gear should be reduced while ensuring the normal traction and starting of the train. With the increase of starting time difference between the master locomotive and the slave locomotive, the pull force in the middle and tail of the marshelling vehicle increases, so the simultaneous operation of the train should be guaranteed as much as possible. The clearance of coupler has obvious influence on the tension of coupler during the start of heavy duty train. Attention should be paid to the maintenance of coupler clearance, and the coupler force can be reduced with the use of traction bar.
    2024,22(9):89-94, DOI: 10.6052/1672-6553-2024-015
    Abstract:
    The development of remote sensing satellites has made Spaceborne cryocooler used more widely, the cryocooler provides the required temperature environment for the detector, but also brings micro-vibration interference which will affect the performance of detector. Therefore, it is necessary to suppress the micro-vibration of cryocooler. In this paper, a passive vibration isolation device for cryocooler is designed based on relaxation damper and layout of three-point uniform support, the isolation performance of the device is analyzed. The transfer characteristics of dynamic model and finite element model are compared. The result shows that the vibration isolation efficiency of the designed passive vibration isolation device for the main frequency, double frequency and triple frequency can achieve 90%,95% and 97%. This paper can provide significant reference for designing such kind of passive vibration isolation device for sapceborne cryocooler.
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    2014,12(3):193-200, DOI: 10.6052/1672-6553-2014-046
    [Abstract] (3125) [HTML] (0) [PDF 748.46 K] (17524)
    Abstract:
    The spacecraft's ability to adapt to the harsh dynamics environment is critical for the whole space mission. Vibration test control technology is the key part of the dynamic environment test. The current progress, fundamental principles and key techniques development level of the spacecraft and vibration control algorithms overseas were analyzed. The basic ideas, effective ways and suggestions were given to domestic following research.
    2017,15(5):385-405, DOI: 10.6052/1672-6553-2017-039
    [Abstract] (1908) [HTML] (0) [PDF 1.91 M] (17327)
    Abstract:
    In this review article, the growth and related academic communications in the dynamics of multibody systems are firstly surveyed. Then, the recent advances in the numerical algorithms for solving the dynamic equations of flexible multibody systems, the contact/impact dynamics of flexible multibody systems and the deployment of flexible space structures are systematically reviewed, together with several open problems of concern. Finally, some suggestions are made for the prospective researches on the dynamics of flexible multibody systems.
    2014,12(1):18-23, DOI: 10.6052/1672-6553-2013-068
    [Abstract] (3060) [HTML] (0) [PDF 1.13 M] (17079)
    Abstract:
    The electromechanical coupling model of cantilevered piezoelectric harvester was developed by considering the nonlinearities of piezoelectric material, based on Hamilton theory, Rayleigh-Ritz method, Euler-Bernoulli beam theory and constant electrical field across the piezoelectric element. The response characteristics of the system were investigated numerically, and the influences of piezoelectric material nonlinear coefficient on the system response were analyzed. By exploring the nonlinear characteristics of the piezoelectric vibrator near the resonant frequency, the nature of the multi-solutions and jump phenomena in the resonance region was revealed. The results were verified experimentally. which provides a theoretical basis for the study of nonlinear mechanism of piezoelectric power generation system.
    2014,12(3):243-247, DOI: 10.6052/1672-6553-2014-054
    [Abstract] (2466) [HTML] (0) [PDF 1.07 M] (16675)
    Abstract:
    Random vibration test is very important to the aerospace equipment. The windage of ASD outside the frequency bandwidth was analyzed. The reason, premonition, affection and effective way were given. And the commonly used random vibration test and vibration test metrology standard for the ASD outside the frequency bandwidth were analyzed.
    2015,13(5):361-366, DOI: 10.6052/1672-6553-2014-064
    [Abstract] (1256) [HTML] (0) [PDF 826.19 K] (16491)
    Abstract:
    Dynamic and control systems often contain uncertain parameters that may result in uncertain predictions. In the interest of quantifying the effects of parameter uncertainties on response variability, this paper develops a stochastic response surface based method for the sensitivity analysis of uncertain parameters. Stochastic response surfaces were firstly constructed to describe the explicit relationships between uncertain parameters and responses. Then partial derivations were performed on the mathematical expressions of stochastic response surfaces in order to obtain sensitivity indices that simultaneously embody the effects of parameter means and standard deviations. Lastly, the developed method has been verified against a numerical cantilever beam containing uncertain geometric and material parameters. The sensitivity analysis results were compared with those given by the analysis of variance method.
    2016,14(2):97-108, DOI: 10.6052/1672-6553-2015-009
    [Abstract] (2449) [HTML] (0) [PDF 1.87 M] (16449)
    Abstract:
    Based on the current research status of multi agents system control theory and technology, the paper makes a detailed overview for unmanned ground systems. From two aspects of behaviour and task cooperative control for multi agents, the relevant theory and application problem is discussed. Moreover, some existed open problems are presented and a possible future development is proposed. For unmanned ground systems, cooperative control will be of great importance in promoting social and military benefits and maximizing the executive function of ground mission.
    2014,12(3):225-229, DOI: 10.6052/1672-6553-2014-051
    [Abstract] (2432) [HTML] (0) [PDF 1.38 M] (16279)
    Abstract:
    Based on the staggered solution procedure of ANSYS and CFX software, the fluid structure coupling response of projectile during tail slapping has been researched. Structural response was simulated by using FEM and flow field was simulated by using inhomogeneous model and SST turbulence model. Finally, the influences of fluid structure coupling effect have been analyzed and the change law of body stress has been given.
    2013,11(1):12-19, DOI: 10.6052/1672-6553-2013-003
    [Abstract] (2406) [HTML] (0) [PDF 530.95 K] (16128)
    Abstract:
    The dynamics of the whole aero-engine system has always been the important part that cannot be neglected in the research and design of the engine, as the framework of the engine, the vibration of the casing directly reflects the level of the whole aero engine vibration. In this paper, an analysis was made on the research of the problems and fault classification of aero-engine casing dynamics, and an overview was made on the research of present situation, development trend, problems and solutions of the domestic and foreign of casing dynamics, which expanded the present situation of the Inclusiveness problems of aero-engine casing dynamics. Finally, some proposals were put forward for the development of the casing dynamics suitable for our country aero-engine technology level.
    2014,12(3):269-273, DOI: 10.6052/1672-6553-2014-043
    [Abstract] (3326) [HTML] (0) [PDF 336.30 K] (16071)
    Abstract:
    Aiming at the problem that the longitudinal modes of structural system of rocket need to be identified from its integral modes in engineering, a method that automatically identifies the longitudinal modes of structural system of rocket was proposed according to the theory of modal effective mass. Taking the vibration characteristics of system with lumped mass as a computing example, applying the finite element software, the beam model of system with lumped mass was established, and the longitudinal modes of the system were automatically identified based on the method. Compared with the system modal information calculated by the method of modal analysis, this automatic identification method not only can accurately identify the longitudinal modes of vibrating system, but also has automatic and high efficiency identification feature. It provides a theoretical basis for the dynamic model of POGO vibrating system in liquid rockets and other model of engineering systems to be accurately and promptly established.
    2012,10(1):21-26, DOI:
    [Abstract] (853) [HTML] (0) [PDF 567.09 K] (15906)
    Abstract:
    A discrete finite dimensional dynamical model was built to describe the space large overall motion of tethered satellite system with an infinite dimensional viscoelastic tether in a long time. The tethered satellite system is a complex nolinear dynamic system. Considering the tether’s viscoelasticity, distributed mass and space form, the established improved bead model can meticulously describe the tether’s vertical and horizontal vibration. According to tether’s characteristic of tensile and not compressive, the slack tether unit model was set up to accurately reflect real stress of tether. The determination of the number of degrees of freedom of the system was studied. Based on numerical integral calculation, the dynamic response was obtained via numerical simulation of the deployment, retrievement and retainment process of tethered satellite system in a long time. The result is convergent. The simulation proves the important role of the stable equilibrium position in the dynamics of tethered space system.
    2008,6(4):301-306, DOI:
    [Abstract] (1241) [HTML] (0) [PDF 0.00 Byte] (15845)
    Abstract:
    The problem of P and PI feedback control to a time delay system was investigated,with the emphasis on the determination of the feedback gains that ensured the asymptotical stability of the delayed system. By means of Lambert W function,the feedback gain of P control can be expressed explicitly,so that the optimal feedback gain can be easily obtained. For the system under a PI control,the stable region of the feedback gains was determined on the basis of stability switches and D subdivision,and the optimal feedback gains that enabled the system to admit maximal stable margin were figured out numerically by using Lambert W function. From the viewpoint of computation,the present method is much simpler than the available methods.
    2014,12(2):183-187, DOI: 10.6052/1672-6553-2014-025
    [Abstract] (1378) [HTML] (0) [PDF 811.52 K] (15658)
    Abstract:
    PMSM due to little harmonic, high precision torque, commonly is used in the servo system and the high performance speed control system. In this paper,the physical model of PMSM is simplified and the mathematical model of the motor is established in order to facilitate research.Thispaper uses id=0 control manner which is the simplest manner is vector control methods,motor electromagnetic torque equation is established based on rotor field oriented vector control.The system model, speed and current control block are build and simulated with MATLAB/Simulink.Simulation results shows that the waveform is consistent with thoretical analysis,the model has fast response and small overshoot.The system runs stably with good dynamic and static characteristics. The simulation makes full use of modularization design. All the parameters and their influence on the system can be changed and observed.It also can easily validate the control strategies and select the most suitable one. So this kind of simulation is good for system design and adjusting and validating.
    2014,12(3):205-209, DOI: 10.6052/1672-6553-2014-059
    [Abstract] (2060) [HTML] (0) [PDF 467.15 K] (13375)
    Abstract:
    This paper investigated the passive nonlinear vibration control method used for energy absorbing in structures of spacecrafts. The structure and the dynamic model of the nonlinear energy sink which could adapt to the space environment were proposed. As nonlinear spring could not be acquired easily in reality, we proposed a new design for the NES based on employing an asymmetric NES force which was generated by two pairs of aligned permanent magnets. Then, the dynamic model for a cantilever beam structure coupled with nonlinear energy sink had been built theoretically. In addition, the passive vibration suppression effect of the nonlinear energy sink on the cantilever beam structure under transient excitation had been analyzed through Galerkin method and numerical analysis method. The results showed that the NES acquired up to 92% dissipation of the system energy imposed by shock excitation, hence the NES could adapt to the space environment and improve the reliability of space system.
    2014,12(3):283-288, DOI: 10.6052/1672-6553-2014-061
    [Abstract] (3013) [HTML] (0) [PDF 479.50 K] (12550)
    Abstract:
    A method was presented to analyze the nonlinear flutter. Based on this method, the flutter characteristics of the high aspect wing were illustrated. The numerical results show that the flutter speed is decreased when the first horizontal bending mode involved. Secondly, this study discussed how the main direction of the composite influenced the character of the nonlinear vibration and flutter, and established the method of the flutter clipping to the high aspect wing. And the result shows that the stiffness of structure can be changed by changing the main direction of the composite. It mainly changes the horizontal bending mode, makes the main direction tend to the trailing edge, and then makes the section line move to the leading edge. Further analyzing the nonlinear flutter reveals that it is the changing of the horizontal bending mode that causes the flutter speed change obviously. And by the section line of this mode moves ahead, the flutter speed will become larger. In the study, two examples were illustrated to validate its truthiness.
    2013,11(4):357-362, DOI: 10.6052/1672-6553-2013-041
    [Abstract] (1432) [HTML] (0) [PDF 350.50 K] (10813)
    Abstract:
    At present, the main task of designing a mounting system of automotive engine powertrain is to select appropriate stiffness, position and angle of mounting components so that free-vibration modal frequency of the mounting system can avert from the exciting-force frequency at the idle speed of the engine and the natural frequency of vibration of the vehicle body and that the decoupling degree of each mode shape is increased as far as possible, so as to improve the vibration-isolation effect of the mounting system. The design of a mounting system based on strict decoupling at predetermined frequencies is to make the modal frequencies of the designed mounting system completely equal to the frequencies predetermined in accordance with the frequency planning of automotive design, and to enable strict decoupling of each mode shape of each mode, i.e., the decoupling degree of vibration energy in every direction equals to 1. Based on a free-vibration equation for a mounting system, this paper presents an equation system for designing a mounting system with strict decoupling at predetermined frequencies, provides a solving method for this equation system by using the theory of generalized inverse matrix or method of constructing function, so as to provide an optimal design method more efficient and simpler than the current modal optimization method of mounting system. Relevant example has validated the correctness of equations and solving method of the strict-decoupling design at predetermined frequencies.
    2016,14(3):247-252, DOI: 10.6052/1672-6553-2015-052
    [Abstract] (1823) [HTML] (0) [PDF 2.18 M] (7982)
    Abstract:
    Tires are the only carrier of the contact between the vehicle and road surface. Their mechanical property is important for analysis and control on the vehicle dynamic response. At present, the tire simulation mostly focuses on the steady state model. But it can not describe the dynamic characteristic of the tire accurately. Therefore, it plays a significant role to add the dynamic tire model in the vehicle dynamics simulation. The tire friction model in the multi body dynamical software ADAMS is static, where the friction is regarded as a static value. However, in actual, the friction between the tire and road surface is dynamic, and it should be a dynamic function of the relative velocity and displacement. To this end, in this paper, the dynamic tire LuGre model using the Matlab/Simulink software is constructed. Through connecting the interface with Adams/Car, co simulation between the vehicle model and the simulink tire model is carried out in order to achieve the dynamic contact between tire and road and improve the accuracy of vehicle system analysis.
    2014,12(1):36-43, DOI: 10.6052/1672-6553-2013-110
    [Abstract] (2156) [HTML] (0) [PDF 2.22 M] (6507)
    Abstract:
    The coupling nonlinear dynamic model of dual rotor system was established by using finite element method, and then the critical speed of revolution and mode shape were calculated by using the software MATLAB. In addition, the unbalance responses of dual rotor system were studied, and the vibration performances in different speeds of dual rotor casing systems were obtained. The research provides a theoretical basis for the design of the dual rotors system in engineering.
    2014,12(3):253-258, DOI: 10.6052/1672-6553-2014-056
    [Abstract] (2047) [HTML] (0) [PDF 1.00 M] (5104)
    Abstract:
    Taking account of the structural stiffness and the low order vibration frequencies, two schemes of multi-objective topology optimization were proposed to obtain the best aircraft lifting-surface structural design. Based on penalized density theory, the scheme one (named as constrain method) is to convert the multi-objective optimization to single-objective optimization by considering the minimum structural mass as the objective with constraints of reference points displacements and the low order vibration frequencies. The scheme two (named as the combination of constrain method and criterion function method) settles the multi-objective optimization by defining combined compliance index (CCI) as the objective, with the constraints of volume fraction and the low order vibration frequencies. The CCI is the function of structural compliance and low order vibration frequencies. Numerical results demonstrate the proposed schemes not only realize reducing the structural mass but also raise the first and second order frequencies.
    2014,12(3):201-204, DOI: 10.6052/1672-6553-2014-048
    [Abstract] (2126) [HTML] (0) [PDF 296.79 K] (4544)
    Abstract:
    Non-linear factors cannot be avoided in the design of aircraft structures. In this paper, a two-degree-of-freedom airfoil and cubic stiffness nonlinearities in pitching degree-of-freedom operating in supersonic flight speed regimes has been analyzed. The averaging method and the theory of flutter were used to analyze the nonlinear dynamic system of the dualistic airfoil in the supersonic flow. Then the correctness of the theoretical calculation was verified by numerical calculation, and the analysis result was given.
    2014,12(1):62-66, DOI: 10.6052/1672-6553-2013-097
    [Abstract] (1544) [HTML] (0) [PDF 832.87 K] (4360)
    Abstract:
    A spline finite point method was presented to study the natural frequency of arch. The displacement mode shape function of the arch free vibration was simulated with a linear combination of cubic B spline. The free vibration frequency equation of arch structures was derived according to Hamilton principle, in which the effect of the dead load was considered. Meanwhile, the effect of the dead load on the natural frequency of arch structures was analyzed. The results show that the natural frequency of arch is reduced. The effect of influence depends on the stiffness of the arch itself. When the arch stiffness is certain, the bigger the rise span ration and the radius to thickness ration, the higher the effect of the dead load on the natural frequency of arch structures.

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