Xu Yang

Bio: Xu Yang is an academic researcher from Harbin Engineering University. The author has contributed to research in topics: Vibration isolation & Silencer. The author has an hindex of 4, co-authored 7 publications receiving 34 citations.

Three-dimensional vibration isolation device applicable to low-frequency vibration

Abstract: The invention aims at providing a three-dimensional vibration isolation device applicable to low-frequency vibration On a horizontal plane, a decoupling bracket, steel shafts, and an aluminum slide block realizes decoupling of vibration displacement in X and Y directions; a large circular permanent magnet and a small circular permanent magnet serve as negative stiffness elements, and springs serve as positive stiffness elements, thereby forming a low-frequency vibration isolation system of the horizontal plane; in a vertical direction, oblique springs serve as negative stiffness elements due to geometrical characteristics, and a support spring serves as a positive stiffness element to form a low-frequency vibration isolation system in Z direction; and a three-dimensional low-frequency vibration isolation system is formed by combining the two systems According to the device, the permanent magnets or the springs serve as the negative stiffness elements or positive stiffness elements, lower-frequency vibration isolation is achieved; displacement decoupling in the X, Y and Z directions is achieved; lower dynamic stiffness in the Z direction and an XY plane can be obtained, and a greater carrying capacity can be ensured at the same time; the input energy is not required; and a static balance position can be adjusted to ensure that the vibration occurs near zero stiffness

Double-layer active-passive electromechanical integrated type vibration isolation device

Abstract: The invention discloses a double-layer active-passive electromechanical integrated type vibration isolation device The double-layer active-passive electromechanical integrated type vibration isolation device comprises a passive upper rubber vibration isolator (a), an intermediate framework structure (c), a mounting bottom plate (d), four electromagnetic exciters (b), integrated type control signal conditioning equipment and acceleration signal conditioning equipment (f), the intermediate framework structure (c) is arranged between the upper rubber vibration isolator (a) and the mounting bottom plate (d), the four electromagnetic exciters (b) serve as active executing mechanisms symmetrically arranged at the left and right sides of the intermediate framework structure (c), and the integrated type control signal conditioning equipment and acceleration signal conditioning equipment (f) are symmetrically arranged in front and rear grooves of the intermediate framework structure (c) The double-layer active-passive electromechanical integrated type vibration isolation device can well inhibit the vibration due to wide-frequency band external disturbance excitation, and the double-layer active-passive electromechanical integrated type vibration isolation device is mainly used for controlling the vibration of different kinds of marine diesel engines, steam turbines, pumps, the like rotating and reciprocating mechanical equipment, nuclear emergency power generator sets and the like large power equipment

High-pressure liquid charging pipeline integrated active silencer

Abstract: The invention provides a high-pressure liquid charging pipeline integrated active silencer. The high-pressure liquid charging pipeline integrated active silencer mainly comprises a cylindrical housing, an actuator arranged in the middle of the housing and based on tubular piezoelectric ceramics, sensors on the inner side of upstream and downstream pipe sections, and a signal pick-up and conditioning system, a power amplifying system and a DSP-based high-speed signal processing system between the housing and the pipe section of the actuator. The high-pressure liquid charging pipeline integrated active silencer is usable for a high-pressure liquid charging pipeline, based on the tubular piezoelectric ceramic-based actuator, and highly integrated. The active pipeline silencer is capable of providing counter noise to counteract the original noise in the pipeline according to the frequency, the size and the phase of the internal flow noise in the pipeline measured in real time, and therefore, the silencer is capable of adapting to the change of the noise frequency, wide in silencing bandwidth and good in silencing effect.

Electromagnetic electromechanical coupling circuit tuning vibration absorber

Abstract: Disclosed is an electromagnetic electromechanical coupling circuit tuning vibration absorber. The electromagnetic power generation Faraday principle is adopted, a rotor magnetic field is cut through a coil for converting vibrating kinetic energy into electric energy, then, the coil is connected to a load circuit, and circuit current changes by adjusting impedance characteristics of the load circuit. Due to the fact that the current-carrying coil generates ampere force in a magnetic field, different currents generate ampere force of different magnitudes, different feedback effects can be generated on an existing mechanical system, and therefore different changes of the rigidity and damping of the existing mechanical system are caused through an electromechanical coupling effect. The impedance characteristics can be adjusted through the digital circuit. Compared with traditional mechanical adjustment, adjustment of the electromagnetic coupling mode is rapider and easier, the needed control system is relatively simple and stable, and integration, microminiaturization and low energy consumption of the adjustable vibration absorber can be better achieved.

The Fractional Complex Transform: a Novel Approach to the Time-Fractional SCHRÖDINGER Equation

Abstract: This paper presents a thorough study of a time-dependent nonlinear Schrodinger (NLS) differential equation with a time-fractional derivative. The fractional time complex transform is used to conver...

Advances in mechanical metamaterials for vibration isolation: A review

Abstract: The adverse effect of mechanical vibration is inevitable and can be observed in machine components either on the long- or short-term of machine life-span based on the severity of oscillation. This in turn motivates researchers to find solutions to the vibration and its harmful influences through developing and creating isolation structures. The isolation is of high importance in reducing and controlling the high-amplitude vibration. Over the years, porous materials have been explored for vibration damping and isolation. Due to the closed feature and the non-uniformity in the structure, the porous materials fail to predict the vibration energy absorption and the associated oscillation behavior, as well as other the mechanical properties. However, the advent of additive manufacturing technology opens more avenues for developing structures with a unique combination of open, uniform, and periodically distributed unit cells. These structures are called metamaterials, which are very useful in the real-life applications since they exhibit good competence for attenuating the oscillation waves and controlling the vibration behavior, along with offering good mechanical properties. This study provides a review of the fundamentals of vibration with an emphasis on the isolation structures, like the porous materials (PM) and mechanical metamaterials, specifically periodic cellular structures (PCS) or lattice cellular structure (LCS). An overview, modeling, mechanical properties, and vibration methods of each material are discussed. In this regard, thorough explanation for damping enhancement using metamaterials is provided. Besides, the paper presents separate sections to shed the light on single and 3D bandgap structures. This study also highlights the advantage of metamaterials over the porous ones, thereby showing the future of using the metamaterials as isolators. In addition, theoretical works and other aspects of metamaterials are illustrated. To this end, remarks are explained and farther studies are proposed for researchers as future investigations in the vibration field to cover the weaknesses and gaps left in the literature.

Vibration control of rotating sandwich cylindrical shell-reinforced nanocomposite face sheet and porous core integrated with functionally graded magneto-electro-elastic layers

Abstract: This article presents an analytical approach to study the vibration control of rotating sandwich cylindrical shell-reinforced nanocomposite face sheet and porous core integrated with functionally graded magneto-electro-elastic layers using first-order shear deformation theory of shells. By considering the Coriolis and centrifugal force and also using Hamilton’s principle and Maxwell equations, the governing equations of motion for rotating sandwich cylindrical shell are derived. The differential quadrature method is employed to determine the forward and backward linear frequency of rotation sandwich cylindrical shell for different boundary conditions. Detailed parametric studies are carried out to investigate influences of volume fraction of carbon nanotube in face sheet layers, temperature, distribution types of porosity, different boundary conditions, angular velocity and electrical and magnetic control coefficients on vibration control of sandwich cylindrical shell. The results of the necessary parameters can be used as benchmarks for design in important industries such as low- or high-speed rotor and turbine manufacturing.