A comparison investigation of the contact models for contact and vibration features of cylindrical roller bearings

2019 ◽  
Vol 36 (5) ◽  
pp. 1656-1675
Author(s):  
Jing Liu ◽  
Linfeng Wang ◽  
Zhifeng Shi ◽  
Wennian Yu ◽  
Huifang Xiao
Keyword(s):  
Finite Element ◽  
Contact Stress ◽  
Contact Stiffness ◽  
Computational Results ◽  
Contact Deformation ◽  
Calculation Methods ◽  
Fe Method ◽  
Content Type ◽  
Contact Models ◽  
Cylindrical Roller

Purpose The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of rotating machinery. The contact deformation between the roller and the raceway is an essential research topic for the CRBs. The contact deformation between the roller and the raceway can greatly affect vibration characteristics and fatigue life of the CRBs. In this investigation, six different methods are adopted to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Design/methodology/approach In this paper, the contact deformations and the contact stiffnesses between the roller and the raceway of a CRB obtained by various well-known empirical methods (Lundberg’s, Palmgren’s, Houpert’s, Cheng’s and Hertzian methods) are directly compared with those by the finite element (FE) method. A two degree-of-freedom (2 DOF) dynamic model of the CRB is applied to investigate the effects of the contact stiffness obtained by different line contact deformation calculation methods on the vibration characteristics, such as the root mean square (RMS), the peak to peak (PTP), the crest factor and the kurtosis of the displacement, velocity and acceleration of the inner raceway. Findings The computational results show that different calculation methods for the contact deformations between rollers and raceways have significant effects on the vibrations of the CRB. It is found that that the differences of computational results obtained by Palmgren’s and Lundberg’s models with respect to the FE method are smaller than those by the other three methods, i.e. Houpert’s, Cheng’s and Hertzain models. The amplitude and peak frequency of the frequency response functions from Palmgren’s method are much more similar to those from the finite element method. The above results indicate that Palmgren’s method is a better calculation method for predicting the contact deformations and dynamics of the CRBs. Originality/value This work adopts six different methods to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Moreover, a vibration model of a CRB is used to investigate the effect of contact stiffness obtained by the above methods on the vibrations of the CRB. The works can give some guidance for the accurate analytical method for calculating the contact deformations between rollers and raceways and the vibrations of the CRB.

Dynamic contact stress and frictional heat analysis of femoral head-on-acetabular cup interface based on calculation and simulation methods

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xingxing Fang ◽  
Dahan Li ◽  
Yucheng Xin ◽  
Songquan Wang ◽  
Yongbo Guo ◽  
...  
Keyword(s):  
Finite Element ◽  
Femoral Head ◽  
Contact Stress ◽  
Contact Area ◽  
Gait Cycle ◽  
Dynamic Change ◽  
Dynamic Contact ◽  
Frictional Heat ◽  
Acetabular Cup ◽  
Content Type

Purpose The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a gait cycle. Design/methodology/approach In this paper, four common femoral head-on-acetabular cup contact pairs are used as the research objects, mathematical calculations and finite element simulations are adopted. The contact model of hip joint head and acetabular cup was established by finite element simulation to analyze the stress and temperature distribution of the contact interface. Findings The results show that the contact stress of the head-on-cup interface is inversely proportional to the contact area; high contact stress directly leads to greater frictional heat. However, hip joints with metal-on-polyethylene or ceramic-on-polyethylene paired interfaces have lower frictional heat and show a significant temperature rise in one gait cycle, which may be related to the material properties of the acetabular cup. Originality/value Previous studies about calculating the interface frictional heat always ignore the dynamic change process in the contact load and the contact area. This study considered the dynamic changes of the contact stress and area of the femoral head-on-acetabular cup interface, and four common contact pairs were systematically analyzed.

Contact Stiffness Parameters for Finite Element Modeling of Contact

2019 ◽  
Vol 799 ◽  
pp. 211-216
Author(s):  
Alina Sivitski ◽  
Priit Põdra
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Contact Stiffness ◽  
Influential Factors ◽  
Element Analysis ◽  
Normal Contact ◽  
Element Modeling ◽  
Contact Models ◽  
Machine Elements ◽  
Normal Contact Pressure

Contact modeling could be widely used for different machine elements normal contact pressure calculations and wear simulations. However, classical contact models as for example Hertz contact models have many assumptions (contact bodies are elastic, the contact between bodies is ellipse-shaped, contact is frictionless and non-conforming). In conditions, when analytical calculations cannot be performed and experimental research is economically inexpedient, numerical methods have been applied for solving such engineering tasks. Contact stiffness parameters appear to be one of the most influential factors during finite element modeling of contact. Contact stiffness factors are usually selected according to finite element analysis software recommendations. More precise analysis of contact stiffness parameters is often required for finite element modeling of contact.

Determination of Contact Stiffness of Rod-Fastened Rotors Based on Modal Test and Finite Element Analysis

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
Yanchun Zhang ◽  
Zhaogang Du ◽  
Liming Shi ◽  
Shaoquan Liu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Contact Stress ◽  
Contact Stiffness ◽  
Turbine Rotor ◽  
Modal Parameters ◽  
Element Analysis ◽  
Modal Test ◽  
Surface Contact ◽  
The Relationship

A series of simplified rod-fastened rotors, which have different surface contact roughness are manufactured and their modal parameters under different pretightening force, are measured in free-free state. The concept of surface contact stiffness is introduced to simulate the influence of pretightening force on modal parameters of these simplified rod-fastened rotors using finite element method. The experiment measured results are compared and fitted to the finite element analysis results and the relationship between contact stiffness and contact stress is established in which the contact stress is defined by the pretightening force. The relationship is then applied on the modal analysis of a real gas turbine rotor, and its modal test results and finite element analysis results are consistent with each other, proving that the relationship and the described determination method of contact stiffness based on modal test and finite element analysis are effective.

The Effects of Load on the Radial Bearing Properties of Pre-Loaded Cylindrical Roller Bearings

2011 ◽  
Vol 130-134 ◽  
pp. 2306-2310
Author(s):  
Yan Gang Wei ◽  
Meng Sun
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Contact Stress ◽  
Radial Load ◽  
The Finite Element Method ◽  
Roller Bearings ◽  
Radial Stiffness ◽  
Maximum Contact Stress ◽  
Maximum Contact ◽  
Cylindrical Roller

According to the theory of contact mechanics, the radial stiffness, the maximum contact stress, and the maximum radial load of pre-loaded cylindrical roller bearings, including both solid roller and hollow roller bearings, are calculated with the finite element method. The effects of load on the radial stiffness, the maximum contact stress, and the maximum radial load of bearing are analyzed. The analysis results show that the effect of load on the radial stiffness is complex. Under the different magnitude loads, the effects of both hollowness and interference magnitude on the radial stiffness and on the maximum contact stress are not same. Thus the effects of load magnitude must be considered in the design and application of pre-loaded cylindrical roller bearings.

Large-deformation finite element analysis of the interaction between concrete cut-off walls and high-plasticity clay in an earth core dam

2017 ◽  
Vol 34 (4) ◽  
pp. 1126-1148 ◽  
Author(s):  
Xiang Yu ◽  
Degao Zou ◽  
Xianjing Kong ◽  
Long Yu
Keyword(s):  
Finite Element ◽  
Large Deformation ◽  
Small Strain ◽  
Fe Analysis ◽  
Hyperbolic Model ◽  
High Plasticity ◽  
Fe Method ◽  
Content Type ◽  
Earth Core ◽  
High Plasticity Clay

Purpose A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This issue has been often studied using the small-strain finite element (FE) method in previous research. This paper aims to research the interaction behaviour between a concrete cut-off wall and high-plasticity clay using large-deformation FE analyses. Design/methodology/approach The re-meshing and interpolation technique with a small-strain (RITSS) method was performed using an independently developed program and adopted for large-deformation FE analyses, and a suitable element size for the high-plasticity clay region was suggested. The layered construction process of an earth core dam built on thick alluviums was simulated using the RITSS method incorporating a hyperbolic model for soil. Findings The RITSS method is an effective technique for simulating the soil–structure interaction during dam construction. The RITSS analysis predicted a higher maximum principle stress of the concrete cut-off wall and higher stress levels in the high-plasticity clay region than small-strain FE analysis. Originality/value A practical method for large-deformation FE analysis was advised and was used for the first time to study the interaction between a concrete cut-off wall and high-plasticity clay in dam engineering. Large deformation in the high-plasticity clay was handled using the RITSS method. Moreover, the penetration process of the concrete cut-off wall into the high-plasticity clay was captured using a favourable element shape and mesh density.

scholarly journals Model refinements of transformers via a subproblem finite element method

2017 ◽  
Vol 36 (1) ◽  
pp. 309-319 ◽  
Author(s):  
Patrick Dular ◽  
Patrick Kuo-Peng ◽  
Mauricio Valencia Ferreira da Luz ◽  
Laurent Krahenbuhl
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Local Fields ◽  
Fe Method ◽  
Content Type ◽  
Flux Tubes ◽  
Magnetic Cores ◽  
Complex Models ◽  
Three Dimensional Models ◽  
Correction Step

Purpose This paper aims to develop a methodology for progressive finite element (FE) modeling of transformers, from simple to complex models of both magnetic cores and windings. Design/methodology/approach The progressive modeling of transformers is performed via a subproblem (SP) FE method. A complete problem is split into SPs with different adapted overlapping meshes. Model refinements are performed from ideal to real flux tubes, one-dimensional to two-dimensional to three-dimensional models, linear to nonlinear materials, perfect to real materials, single wire to volume conductor windings and homogenized to fine models of cores and coils, with any coupling of these changes. Findings The proposed unified procedure efficiently feeds each SP via interface conditions (ICs), which lightens mesh-to-mesh sources transfers and quantifies the gain given by each refinement on both local fields and global quantities, with a clear view on its significance to justify its usefulness, if any. It can also help in education with a progressive understanding of the various aspects of transformer designs. Originality/value Models of different accuracy levels are sequenced with successive additive corrections supported by different adapted meshes. The way the sources act at each correction step, up to the full models with their actual geometries, is given a particular care and generalized, allowing the proposed unified procedure. For all the considered corrections, the sources are always of IC type, thus only needed in layers of FE along boundaries, which lightens the required mesh-to-mesh projections between subproblems.

scholarly journals Adaptive finite element method for eigensolutions of regular second and fourth order Sturm-Liouville problems via the element energy projection technique

2017 ◽  
Vol 34 (8) ◽  
pp. 2862-2876 ◽  
Author(s):  
Si Yuan ◽  
Kangsheng Ye ◽  
Yongliang Wang ◽  
David Kennedy ◽  
Frederic W. Williams
Keyword(s):  
Finite Element ◽  
Fourth Order ◽  
Variable Coefficients ◽  
Adaptive Finite Element Method ◽  
Adaptive Finite Element ◽  
Fe Method ◽  
Eigenvalues And Eigenfunctions ◽  
Content Type ◽  
Sturm Liouville ◽  
Element Energy Projection

Purpose The purpose of this paper is to present a numerically adaptive finite element (FE) method for accurate, efficient and reliable eigensolutions of regular second- and fourth-order Sturm–Liouville (SL) problems with variable coefficients. Design/methodology/approach After the conventional FE solution for an eigenpair (i.e. eigenvalue and eigenfunction) of a particular order has been obtained on a given mesh, a novel strategy is introduced, in which the FE solution of the eigenproblem is equivalently viewed as the FE solution of an associated linear problem. This strategy allows the element energy projection (EEP) technique for linear problems to calculate the super-convergent FE solutions for eigenfunctions anywhere on any element. These EEP super-convergent solutions are used to estimate the FE solution errors and to guide mesh refinements, until the accuracy matches user-preset error tolerance on both eigenvalues and eigenfunctions. Findings Numerical results for a number of representative and challenging SL problems are presented to demonstrate the effectiveness, efficiency, accuracy and reliability of the proposed method. Research limitations/implications The method is limited to regular SL problems, but it can also solve some singular SL problems in an indirect way. Originality/value Comprehensive utilization of the EEP technique yields a simple, efficient and reliable adaptive FE procedure that finds sufficiently fine meshes for preset error tolerances on eigenvalues and eigenfunctions to be achieved, even on problems which proved troublesome to competing methods. The method can readily be extended to vector SL problems.

scholarly journals On Calculation Methods and Results for Straight Cylindrical Roller Bearing Deflection, Stiffness, and Stress

2011 ◽  
Author(s):  
Timothy L. Krantz
Keyword(s):  
Finite Element ◽  
Dynamic Response ◽  
Material Properties ◽  
Integral Method ◽  
Roller Bearing ◽  
Grid Refinement ◽  
Code Verification ◽  
Calculation Methods ◽  
Surface Integral ◽  
Cylindrical Roller

The purpose of this study was to assess some calculation methods for quantifying the relationships of bearing geometry, material properties, load, deflection, stiffness, and stress. The scope of the work was limited to two-dimensional modeling of straight cylindrical roller bearings. Preparations for studies of dynamic response of bearings with damaged surfaces motivated this work. Studies were selected to exercise and build confidence in the numerical tools. Three calculation methods were used in this work. Two of the methods were numerical solutions of the Hertz contact approach. The third method used was a combined finite element surface integral method. Example calculations were done for a single roller loaded between an inner and outer raceway for code verification. Next, a bearing with 13 rollers and all-steel construction was used as an example to do additional code verification, including an assessment of the leading order of accuracy of the finite element and surface integral method. Results from that study show that the method is at least first-order accurate. Those results also show that the contact grid refinement has a more significant influence on precision as compared to the finite element grid refinement. To explore the influence of material properties, the 13-roller bearing was modeled as made from Nitinol 60, a material with very different properties from steel and showing some potential for bearing applications. The codes were exercised to compare contact areas and stress levels for steel and Nitinol 60 bearings operating at equivalent power density. As a step toward modeling the dynamic response of bearings having surface damage, static analyses were completed to simulate a bearing with a spall or similar damage.

Analyzing Hertzian contact stress developed in a double row spherical roller bearing and its effect on fatigue life

2016 ◽  
Vol 68 (3) ◽  
pp. 361-368 ◽  
Author(s):  
Dhaval B. Shah ◽  
Kaushik M. Patel ◽  
Ruchik D. Trivedi
Keyword(s):  
Finite Element ◽  
Fatigue Life ◽  
Dynamic Loading ◽  
Contact Stress ◽  
Roller Bearing ◽  
Loading Conditions ◽  
Double Row ◽  
Content Type ◽  
Element Approach ◽  
Dynamic Loading Conditions

Purpose The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and fatigue life based on dynamic loading conditions. The paper also aims to recognize the effect of tolerance values on contact stress and fatigue life. Motion and load transmission in spherical roller bearing occurs within the assembly by elliptical curved contacting surfaces. The stress produced by the transmitted load would be very high because of least contacting area between these surfaces. Design/methodology/approach The paper describes a methodology to determine contact stress using analytically as well as finite element method for spherical roller bearing. The comparison for the both each approach for contact stress at different loading condition is carried out. Prediction of fatigue life based on dynamic loading conditions for bearing is also determined using finite element model. The effect on induced contact stress and fatigue life by varying tolerances on inner race dimensions have been found out. Findings The paper suggests that the maximum stress produces at the start or end of the contacting arc under static loading condition in spherical roller bearing. The analytical and finite element approach is in good agreement. The fatigue life prediction is useful for selecting loading conditions for various applications of double row spherical roller bearing. Tolerance level at inner ring raceway radius is kept high because of manufacturing constrain of complex curvature geometric shape. Research limitations/implications The present approach does not consider dynamic loading conditions for contact stress analysis. Therefore, researchers are encouraged to analyze the effect of wear, lubrication and other tribological aspects on bearing life. Originality/value The paper includes determination of contact stress and prediction of fatigue life for spherical roller bearing using analytical as well as finite element approach. The tolerance values at inner race are identified as per manufacturing constraint based on contact stress and fatigue life.

scholarly journals Finite Element Analysis of Contact Stress for Crowned Cylindrical Roller Bearings of Railway Passenger Cars

2020 ◽  
Author(s):  
Chunhui Yang ◽  
Changliang Zhang
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Contact Stress ◽  
Passenger Cars ◽  
Circular Arc ◽  
Roller Bearings ◽  
Railway Passenger ◽  
Contact Stress Distribution ◽  
Cylindrical Roller ◽  
Concentration Phenomenon

The finite element model of NJP3226X1 cylindrical roller bearings was established by ABAQUS software, and the contact stress distribution of three kinds of modification curve(linear, circular-arc, logarithmic) were compared. The results showed that the maximal contact stress of logarithmic modified roller is the minimum, its stress distribute uniformly, and obvious stress concentration phenomenon does not exist, next is circular-arc modified roller, which stress at the two ends is too small and the stress in the middle is large, linear roller has the highest contact stress, and there is an obvious stresses concentration phenomenon at both ends. Through the analysis of the contact stress distribution of the logarithmic shaped roller under different repair quantities, the reasonable repair quantities are obtained.

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