Nonlinear dynamic analysis of a drivetrain composed of cylindrical gears, straight and spiral bevel gears

Download

index.pdf

Date

2018

Author

Yavuz, Şiar Deniz

Metadata

Show full item record

Item Usage Stats

317
views

143
downloads

A nonlinear dynamic model of a drivetrain composed of spur, helical and spiral bevel gears is proposed. Gear shafts are modeled by using Timoshenko beam finite element method and mesh models of gear pairs are used to couple them. Dynamic model includes the flexibilities of bearings as well. Gear backlash and time variation of mesh stiffness are incorporated into the mesh model. Harmonic Balance Method (HBM) with multiple harmonics is applied on the system of nonlinear differential equations in order to obtain a system of nonlinear algebraic equations. Since finite element modelling results in large number of nonlinear equations, receptance method and modal superposition method are introduced to forced response analysis of geared systems with nonlinearities in order to reduce computational effort. This makes it possible to use finite element models for gear shafts. In the calculation of Fourier coefficients, continuous-time Fourier transform, as opposed to the gear dynamics studies that utilize discrete Fourier transform, is used. Thus, convergence problems that arise when the number of nonlinear DOFs is large are avoided. Moreover, analytical integration is employed for the calculation of Fourier coefficients rather than numerical integration in order to further reduce the computational time required. Nonlinear algebraic equations obtained are solved by utilizing Newton’s method with arc-length continuation. The results obtained by HBM are verified by comparing them with those obtained by direct numerical integration, which are computationally demanding. Several parametric studies are performed and response of the system is investigated to demonstrate the effects of system parameters.

Subject Keywords

Gearing, Bevel., Gearing, Spur., Gearing., Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12621882/index.pdf
https://hdl.handle.net/11511/27090

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Nonlinear dynamics of spiral bevel gear pair Önal, Birkan; Ciğeroğlu, Ender; Sarıbay, Zihni Burçay; Department of Mechanical Engineering (2018) Nonlinear dynamics of a generic spiral bevel gear pair used in high speed, high power gearboxes is studied in this thesis. Different tooth ease-off topographies are generated based on real machine settings. Tooth micro geometries are established in order to obtain profile crowning, lengthwise crowning and flank twist topographies. Details of macro and micro geometry and corresponding real machine settings are given in this study. Path of contact, contact stress, directional rotation radius, load share, unlo...
Nonlinear dynamic analysis of a drivetrain composed of spur, helical and spiral bevel gears Yavuz, Siar Deniz; Saribay, Zihni Burcay; Ciğeroğlu, Ender (Springer Science and Business Media LLC, 2020-06-01) This paper proposes a dynamic model for the first time in order to investigate nonlinear time-varying dynamic behavior of a drivetrain including parallel axis gears (such as spur and helical gears) and intersecting axis gears (such as spiral bevel gears). Flexibilities of shafts and bearings are included in the dynamic model by the use of finite element modeling. Finite element models of shafts are coupled with each other by the mesh models of gear pairs including backlash nonlinearity and fluctuating mesh ...
Nonlinear time-varying dynamic analysis of a spiral bevel geared system Yavuz, Siar Deniz; Sarıbay, Zihni Burcay; Ciğeroğlu, Ender (Springer Science and Business Media LLC, 2018-06-01) In this paper, a nonlinear time-varying dynamic model of a drivetrain composed of a spiral bevel gear pair, shafts and bearings is developed. Gear shafts are modeled by utilizing Timoshenko beam finite elements, and the mesh model of a spiral bevel gear pair is used to couple them. The dynamic model includes the flexibilities of shaft bearings as well. Gear backlash and time variation of mesh stiffness are incorporated into the dynamic model. Clearance nonlinearity of bearings is assumed to be negligible, w...
Nonlinear Dynamic Analysis of a Spiral Bevel Geared System Yavuz, Siar Deniz; Saribay, Zihni Burcay; Ciğeroğlu, Ender (2017-02-02) A nonlinear dynamic model of a spiral bevel gear train mounted on flexible shafts and bearings is proposed in this study. The finite element model of shafts is combined with a three-dimensional discrete mesh model of a spiral bevel gear pair. Bearing flexibilities are as well included in the model. Gear backlash is incorporated into the model in the form of clearance-type displacement functions and clearance nonlinearity and stiffness fluctuations of the bearings are neglected. A time-invariant mesh stiffne...
Numerical analysis of thermo-mechanical behavior in flow forming Günay, Enes; Fenercioglu, Tevfik Ozan; Yalçınkaya, Tuncay (2021-01-01) Flow forming is a metal forming process for cylindrical workpieces where high velocity deformation leads to radial thinning and axial extension. In the current study, a thermomechanical, dynamic and explicit finite element model of a flow forming process is developed on ABAQUS software. The model is validated through the comparison of reaction forces and geometry obtained from the experiments. Coolant convection effect is analyzed in conjunction with roller and mandrel conduction cooling to study the therma...

Citation Formats

Ş. D. Yavuz, “Nonlinear dynamic analysis of a drivetrain composed of cylindrical gears, straight and spiral bevel gears,” Ph.D. - Doctoral Program, Middle East Technical University, 2018.