scholarly journals Design, simulation, and adjustment of the longitudinal–torsional composite integrated ultrasonic variable amplitude system

2018 ◽  
Vol 10 (10) ◽  
pp. 168781401880473
Author(s):  
Cunying Zhang ◽  
Bo Zhao ◽  
Ying Niu
Keyword(s):  
Natural Frequency ◽  
Structural Characteristics ◽  
Actual System ◽  
Variable Amplitude ◽  
Theoretical Design ◽  
Element Simulation ◽  
Helical Angle ◽  
Uniform Medium ◽  
Design Value ◽  
Amplitude System

For the longitudinal–torsional composite integrated ultrasonic variable amplitude system with the longitudinal–torsional resonance produced by helical slots in the cone of the launch section, the theoretical design, finite element simulation, and experimental study are carried out. The performed analysis of the helical slot structural characteristics revealed that slot depth, helical angle, and slot width have a strong effect on the natural frequency and ratio of the torsional–longitudinal amplitude. A credible technique for adjusting the deviation of the actual system natural frequency from the theoretical design value by traditional method is proposed based on the adjustment theory of non-uniform medium adopted. The experimentally proved reduction of the above deviation strongly suggests that the approach proposed in this article provides effective theoretical guidance and experimental basis for the study of longitudinal–torsional composite integral ultrasonic variable amplitude system.

scholarly journals An Improved Analytical Method for Vibration Analysis of Variable Section Beam

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Jingjing Feng ◽  
Zhengneng Chen ◽  
Shuying Hao ◽  
Kunpeng Zhang
Keyword(s):  
Natural Frequency ◽  
Analytical Method ◽  
Adomian Decomposition Method ◽  
Theoretical Method ◽  
Element Simulation ◽  
Adomian Decomposition ◽  
Variable Section ◽  
Vibration Problems ◽  
Section Structure ◽  
Section Function

The variable section structure could be the physical model of many vibration problems, and its analysis becomes more complicated either. It is very important to know how to obtain the exact solution of the modal function and the natural frequency effectively. In this paper, a general analytical method, based on segmentation view and iteration calculation, is proposed to obtain the modal function and natural frequency of the beam with an arbitrary variable section. In the calculation, the section function of the beam is considered as an arbitrary function directly, and then the result is obtained by the proposed method that could have high precision. In addition, the total amount of calculation caused by high-order Taylor expansion is reduced greatly by comparing with the original Adomian decomposition method (ADM). Several examples of the typical beam with different variable sections are calculated to show the excellent calculation accuracy and convergence of the proposed method. The correctness and effectiveness of the proposed method are verified also by comparing the results of the several kinds of the theoretical method, finite element simulation, and experimental method.

Influencing Factors Analysis on Comfort of New-Type Precast Assembly Diaphragm

2014 ◽  
Vol 578-579 ◽  
pp. 711-716
Author(s):  
Chong Fang Sun ◽  
Shu Ting Liang ◽  
Xiao Jun Zhu
Keyword(s):  
Finite Element ◽  
Natural Frequency ◽  
Influencing Factors ◽  
Evaluation Criteria ◽  
Simulation Method ◽  
Factors Analysis ◽  
Comfort Evaluation ◽  
Element Simulation ◽  
New Type ◽  
Design Proposal

The paper selected natural frequency and peak acceleration as comfort evaluation criteria. The author tested the new floor comfort under the human-induced loads. The author analyzed new floor comfort by selecting the worst possible scenarioes. The result indicates that the new floor satisfies the comfort requirement. The comparison of test value, theoretical value and finite element value of natural frequency proved that the finite element simulation was reasonable. The author analyzed comfort influencing factors of 7m×7m floor with the same simulation method and proposed a design proposal.

Design and Simulation Analysis of Ultrasonic Rolling Horn

2015 ◽  
Vol 741 ◽  
pp. 15-18
Author(s):  
Le Ping Liu ◽  
Yu An Peng ◽  
Ya Jun Yan ◽  
Qun Qun Gao
Keyword(s):  
3D Model ◽  
Simulation Analysis ◽  
Longitudinal Vibration ◽  
Rolling Process ◽  
Response Analysis ◽  
Experimental Basis ◽  
Harmonic Response ◽  
Theoretical Design ◽  
Design Value ◽  
Harmonic Response Analysis

Considering its important influence on ultrasonic burnishing, ultrasonic horn is the research object in this paper. Take theoretical design of it firstly, then build 3d model by ANSYS11.0 and carry out modal analysis and harmonic response analysis of it. The results show that the longitudinal vibration frequency and the amplitude of transducer are similar to the design value. This validates the feasibility of the design and provides a certain experimental basis for the application of horn in ultrasonic rolling process.

Sensitivity Analysis of Natural Frequency to Structural Parameters of Helical Gear Shaft for Wind Turbine Gearbox

2011 ◽  
Vol 86 ◽  
pp. 380-383 ◽  
Author(s):  
Jun Gang Wang ◽  
Yong Wang ◽  
Yan Tao An ◽  
Qi Lin Huang
Keyword(s):  
Sensitivity Analysis ◽  
Natural Frequency ◽  
Natural Frequencies ◽  
Structural Parameters ◽  
Helical Gear ◽  
Research Subject ◽  
Wind Turbine Gearbox ◽  
Frequency Sensitivity ◽  
Helical Angle ◽  
The Relationship

This paper takes a helical gear shaft as research subject and discusses the main structural parameters to see how it would affect natural frequency sensitivity. The parametrical model of helical gear shaft is created by using software PROE3.0. The natural frequencies and vibration shapes are calculated by the modal analysis. The relationship between the structural parameters and the natural frequency sensitivity can be obtained by means of ANSYS. The result shows that the structural parameters can affect the natural frequency sensitivity. The variation in low order natural frequency is similar to that in high order natural frequency. The effect of module on the natural frequency sensitivity is more remarkable comparing with pressure angle, modification coefficient and helical angle. Selecting structural parameters reasonably may reduce vibration and noise of the helical gear shaft effectively.

Parameter Sensitivities Affecting the Flutter Speed of a MW-Sized Blade

2005 ◽  
Vol 127 (4) ◽  
pp. 538-543 ◽  
Author(s):  
Don W. Lobitz
Keyword(s):  
Natural Frequency ◽  
Structural Characteristics ◽  
Common Knowledge ◽  
Center Of Mass ◽  
Current Trend ◽  
Critical Issue ◽  
Design Parameters ◽  
Blade Design ◽  
Torsional Mode ◽  
Flutter Speed

With the current trend toward larger and larger horizontal axis wind turbines, classical flutter is becoming a more critical issue. Recent studies have indicated that for a single blade turning in still air the flutter speed for a modern 35 m blade occurs at approximately twice its operating speed (2 per rev), whereas for smaller blades (5–9 m), both modern and early designs, the flutter speeds are in the range of 3.5–6 per rev. Scaling studies demonstrate that the per rev flutter speed should not change with scale. Thus, design requirements that change with increasing blade size are producing the concurrent reduction in per rev flutter speeds. In comparison with an early small blade design (5 m blade), flutter computations indicate that the non rotating modes which combine to create the flutter mode change as the blade becomes larger (i.e., for the larger blade the second flapwise mode, as opposed to the first flapwise mode for the smaller blade, combines with the first torsional mode to produce the flutter mode). For the more modern smaller blade design (9 m blade), results show that the non rotating modes that couple are similar to those of the larger blade. For the wings of fixed-wing aircraft, it is common knowledge that judicious selection of certain design parameters can increase the airspeed associated with the onset of flutter. Two parameters, the chordwise location of the center of mass and the ratio of the flapwise natural frequency to the torsional natural frequency, are especially significant. In this paper studies are performed to determine the sensitivity of the per rev flutter speed to these parameters for a 35 m wind turbine blade. Additional studies are performed to determine which structural characteristics of the blade are most significant in explaining the previously mentioned per rev flutter speed differences. As a point of interest, flutter results are also reported for two recently designed 9 m twist/coupled blades.

A Novel Parallel Decoupled Tri-Axis Force Sensor

2014 ◽  
Vol 487 ◽  
pp. 643-648
Author(s):  
Yu Lei Hou ◽  
Zhan Ye Zhang ◽  
Xin Zhe Hu ◽  
Da Xing Zeng
Keyword(s):  
Performance Analysis ◽  
Force Measurement ◽  
Structural Characteristics ◽  
Force Sensor ◽  
Structure Type ◽  
Element Simulation ◽  
Static Performance ◽  
And Performance ◽  
Elastic Sensitive Element ◽  
Component Force

This paper presents a novel parallel tri-axis force sensor with decoupled feature, and performs its performance analysis. Firstly, the structural characteristics of the parallel tri-axis force sensor are introduced and the stress distribution of each limb elastomer is analyzed. To measure the transformation relationship between the force and strain, the electric bridge is formed by pasting strain on the elastic-sensitive element. Then, the finite element simulation of the elastomer is conducted and performance analysis of the sensor is carried out, which shows that the parallel tri-axis force sensor is decoupled, linear and fully-isotropy. The sensor possesses good static performance and can meet the requirements of tri-axis force measurement in general industrial production. The contents of this paper riches the structure type of the multi-component force sensor and will be useful for the research and development of the parallel force sensor.

scholarly journals Research on Radial Vibration of a Circular Plate

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wei Liu ◽  
Donghua Wang ◽  
Hanfeng Lu ◽  
Yumeng Cao ◽  
Pengrong Zhang
Keyword(s):  
Wave Propagation ◽  
Natural Frequency ◽  
Circular Plate ◽  
Classical Method ◽  
Phononic Crystal ◽  
Radial Vibration ◽  
Element Simulation ◽  
Cylindrical Coordinate ◽  
Piezoelectric Effects ◽  
Theoretical Results

Radial vibration of the circular plate is presented using wave propagation approach and classical method containing Bessel solution and Hankel solution for calculating the natural frequency theoretically. In cylindrical coordinate system, in order to obtain natural frequency, propagation and reflection matrices are deduced at the boundaries of free-free, fixed-fixed, and fixed-free using wave propagation approach. Furthermore, radial phononic crystal is constructed by connecting two materials periodically for the analysis of band phenomenon. Also, Finite Element Simulation (FEM) is adopted to verify the theoretical results. Finally, the radial and piezoelectric effects on the band are also discussed.

Dynamics Simulation Analysis of Column for NC Bevel Gear Grinder

2016 ◽  
Vol 693 ◽  
pp. 101-108
Author(s):  
Yong Wang ◽  
Qing Jian Liu ◽  
Tai Yong Wang ◽  
Yu Long Wang ◽  
Zhi Qiang Yu ◽  
...  
Keyword(s):  
Natural Frequency ◽  
Simulation Analysis ◽  
Structural Characteristics ◽  
Dynamic Stiffness ◽  
Element Model ◽  
Weighting Factor ◽  
Dynamics Simulation ◽  
Response Analysis ◽  
Quadratic Programming Method ◽  
Grinding Machine

To avoid the influence of column vibration on machining precision, it is necessary to simulate the stiffness characteristics of the columns for CNC grinding machine, and to optimize the structure of the column by using sensitivity method. Based on structural characteristics of the grinding machine and structural characteristics of the columns, a finite element model is established to simulate and calculate the first-four models of the columns. In order to optimize the structure of the column, a sensitivity analysis is made to calculate the sensitivity of natural frequencies and mass of the column to each panel and ribbed plate. Considering a weighting factor and taking integrated natural frequency of the column as an optimization objective, the mass of the column as a constraint, an optimization equation is established. By a quadratic programming method, the parameter optimization of the column is got as follows: the mass decreased by 4%, integrated natural frequency increased by 2%. Dynamic stiffness of the column has been optimized by harmonic response analysis, the results showed that the largest column in the Z resonance peak reduced by 8.44%.

The Research of Straight Bevel Gear Face-Hobbing Method on General Five-Axis Machine Tool

2016 ◽  
Vol 693 ◽  
pp. 1169-1176
Author(s):  
Yong Wang ◽  
Qing Jian Liu ◽  
Zhi Qiang Yu ◽  
Yu Long Wang ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Natural Frequency ◽  
Structural Characteristics ◽  
Dynamic Stiffness ◽  
Element Model ◽  
Weighting Factor ◽  
Response Analysis ◽  
Harmonic Response Analysis ◽  
Quadratic Programming Method ◽  
Grinding Machine ◽  
Five Axis

To avoid the influence of column vibration on machining precision, it is necessary to simulate the stiffness characteristics of the columns for CNC grinding machine, and to optimize the structure of the column by using sensitivity method. Based on structural characteristics of the grinding machine and structural characteristics of the columns, a finite element model is established to simulate and calculate the first-four models of the columns. In order to optimize the structure of the column, a sensitivity analysis is made to calculate the sensitivity of natural frequencies and mass of the column to each panel and ribbed plate. Considering a weighting factor and taking integrated natural frequency of the column as an optimization objective, the mass of the column as a constraint, an optimization equation is established. By a quadratic programming method, the parameter optimization of the column is got as follows: the mass decreased by 4%, integrated natural frequency increased by 2%. Dynamic stiffness of the column has been optimized by harmonic response analysis, the results showed that the largest column in the Z resonance peak reduced by 8.44%.

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