scholarly journals Influence of Shaft Torsional Stiffness on Dynamic Response of Four-Stage Main Transmission System

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yuan Chen ◽  
Rupeng Zhu ◽  
Guanghu Jin ◽  
Yeping Xiong
Keyword(s):  
Differential Equation ◽  
Fatigue Life ◽  
Dynamic Response ◽  
Fourier Method ◽  
Calculated Data ◽  
Transmission System ◽  
Torsional Stiffness ◽  
Response Analysis ◽  
Lumped Mass ◽  
Lumped Mass Method

Dynamic response analysis has potential for increasing fatigue life of the components in the transmission of a multistage main transmission system. The calculated data can demonstrate the influence of shaft torsional stiffness on dynamic characteristics of the system. Detecting key shafts of the system and analyzing their sensitivity are important for the design of four-stage helicopter gear box. Lumped mass method is applied for dynamic modeling and Fourier method is used to solve differential equation of the system. Results of the analysis indicate that key shafts can be designed carefully to improve the performance of the transmission system.

Seismic Response Analysis on Pile-Soil Couple System by Lumped Mass Method

2011 ◽  
Vol 94-96 ◽  
pp. 1420-1423
Author(s):  
Li Qiang Wang ◽  
Yuan Zhan Wang
Keyword(s):  
Differential Equation ◽  
Seismic Response ◽  
Soil Structure ◽  
Couple System ◽  
Response Analysis ◽  
Lumped Mass ◽  
Deep Foundation ◽  
Lumped Mass Method ◽  
Model Pile ◽  
Mechanical Characters

Pile is widely used as deep foundation in civil engineering. The dynamic interaction between pile and soil is an important problem in the field of soil-structure interaction. This paper established a model to calculate the seismic response of pile-soil couple system. In this model, pile and soil are regarded as lumped mass, soil was divided into two parts: the far region soil and near pile region soil. These two parts are simulated by different mechanical characters. A differential equation of motion of pile-soil couple system was established in the paper, this differential equation can be solved by Wilson-θ method. An example was introduced to study the behavior of pile-soil couple system.

scholarly journals Modeling and Analysis of Amplitude-Frequency Characteristics of Torsional Vibration for Automotive Powertrain

2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Jinli Xu ◽  
Jiwei Zhu ◽  
Feifan Xia
Keyword(s):  
Torsional Vibration ◽  
Transmission Error ◽  
Frequency Characteristics ◽  
Response Analysis ◽  
Lumped Mass ◽  
Modeling And Analysis ◽  
Gear Mesh ◽  
Runge Kutta Method ◽  
Lumped Mass Method ◽  
Automotive Powertrain

In the present paper, the amplitude-frequency characteristics of torsional vibration are discussed theoretically and experimentally for automotive powertrain. A bending-torsional-lateral-rocking coupled dynamic model with time-dependent mesh stiffness, backlash, transmission error etc. is proposed by the lumped-mass method to analysis the amplitude-frequency characteristic of torsional vibration for practical purposes, and equations of motive are derived. The Runge–Kutta method is employed to conduct a sweep frequency response analysis numerically. Furthermore, a torsional experiment is performed and validates the feasibility of the theoretical model. As a result, some torsional characteristics of automotive powertrain are obtained. The first three-order nature torsional frequencies are predicted. Torsional behaviors only affect the vibration characteristics of a complete vehicle at low-speed condition and will be reinforced expectedly while increasing torque fluctuation. Gear mesh excitations have little effects on torsional responses for such components located before mesh point but a lot for ones behind it. In particular, it is noted that the torsional system has a stiffness-softening characteristic with respect to torque fluctuation.

Dynamic Response Analysis of Deepwater Pier with Fluid-Solid Interaction

2010 ◽  
Vol 168-170 ◽  
pp. 161-166 ◽  
Author(s):  
Fan Lei ◽  
Ji Xin Yang ◽  
Hui Liu
Keyword(s):  
Dynamic Response ◽  
Three Dimensional ◽  
Dynamic Effect ◽  
Water Levels ◽  
Response Analysis ◽  
Harmonic Load ◽  
Lumped Mass ◽  
Cable Stayed Bridge ◽  
Influence Of Water ◽  
Three Dimensional Finite Element

The dynamic response of underwater structures is different from those in air because of interaction between fluid and solid. The influence of water depth on dynamic effect of the pier is studied base on a cable-stayed bridge in deep water. The girder of the cable-stayed bridge is simplified as a lumped mass on the top of the pier. The three-dimensional finite element models of pier with different water levels are built to calculate the dynamic characteristics and dynamic response of the pier under the action of harmonic load. The calculated results show that with the rise of water level, the nature frequencies of the pier decrease while the displacement and stress increase.

Theoretical analysis of the vibration modes of the star herringbone gear transmission system

2019 ◽  
Vol 234 (2) ◽  
pp. 358-368
Author(s):  
Feiming Wang ◽  
Sanmin Wang ◽  
Fei Li
Keyword(s):  
Vibration Mode ◽  
Vibration Suppression ◽  
Transmission System ◽  
Gear Transmission ◽  
Vibration Modes ◽  
Lumped Mass ◽  
Coupling Vibration ◽  
Lumped Mass Method ◽  
Gear Transmission System ◽  
Herringbone Gear

The star herringbone gear transmission system has a high load-carrying capacity, and is widely used in aviation, marine power drives, off-road vehicles, and hybrid electric-drive vehicles. Vibration and noise are the key concerns with this transmission system. The lumped mass method was adopted to establish the dynamic model and equations of this system. The modes of the system were analyzed and classified, and the eigenvalues and their multiplicities were determined. The results showed that the system has four typical vibration modes: (1) a lateral-rotational coupled vibration mode (multiplicity m = 1), (2) star gear compound mode (multiplicity m =  N-3, N > 3), (3) center component lateral vibration mode (multiplicity m = 2), and (4) star gear and center gear-coupled mode (multiplicity m = 2). The contribution of this paper lies in the discovery of the coupling vibration modes in the star herringbone gear transmission system and the multiplicities of these modes. This work provides the foundation for further research on vibration suppression for the star herringbone gear transmission system and the theory of planet phasing.

Sign in / Sign up

Export Citation Format

Share Document