Study on the Effect of Ways of Gear Relief on Contact Force of Teeth Face

An accurate finite element contact analysis of helical gears was done directly under ANSYS, while the integrated elastic deformation of the meshed teeth was extracted directly from the finite element contact analysis results, and considered as the main basis of the amount of tooth profile modification. Linear, conic, cubic, and sine relief curve are compiled and established in MATLAB, on which gear models of two ways of modified gear are built. Under the same modified parameters, contact method is used on the proposed finite element models of gears by software LS-DYNA, and the effect of the two ways of gear relief on contact force on teeth face is analyzed. The results show that the effect of a pair of gears relief is better than one gear relief for linear and conic relief curve, and the effect of one gear relief is better than a pair of gears relief for cubic and sine relief curve. So dynamic simulation on modified involute gears has great significance for reducing contact force of teeth face of gears.

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Study on Contact Force of Tooth Profile Modification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.328-330.451 ◽

2011 ◽

Vol 328-330 ◽

pp. 451-456

Author(s):

Yong Ma ◽

Qi Huang ◽

Zhi Feng Lou ◽

Ke Hong Li

Keyword(s):

Finite Element ◽

Dynamic Simulation ◽

Contact Force ◽

Equivalent Stress ◽

Finite Element Models ◽

Contact Method ◽

Elastic Contact ◽

Profile Modification ◽

Single Tooth ◽

Contact Impact

Linear, conic, cubic, and sine relief curve are compiled and established in MATLAB, on which gear models are built in UG and a new method of establishing relief gear models is proposed in this paper. Based on the theory of elastic, contact method is used on the proposed finite element models of gears by software LS-DYNA. Total contact force of teeth face, contact force of single tooth and equivalent stress on relief gears in different cases are obtained. The results show that contact impact existing in meshing between teeth of gears is ameliorated, contact force of tooth face and equivalent stress is reduced. The effect of cubic and sine relief curve is the best. So dynamic simulation on relief gears has great significance for reducing contact force between teeth faces of gears.

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Fracture Reasons and Improvements for the Running Gear of Shearers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.2733 ◽

2012 ◽

Vol 490-495 ◽

pp. 2733-2737

Author(s):

Chun Yu Song ◽

Jing Ru Liu ◽

Xiu Juan Zhang

Keyword(s):

Finite Element ◽

Internal Stress ◽

Contact Force ◽

Maximum Stress ◽

Contact Analysis ◽

Finite Element Models ◽

Elastic Contact ◽

Gear Teeth ◽

Calculation Results ◽

Contact Spots

Running traction mechanism of shearers is adopted as the analysis object in this paper. The finite element models for the elastic contact analysis between the running gears and pin-rails are created. When the gears are running, the variation principles of contact spots, contact force, and internal stress for the gears and pin-rails at the different contact positions are analyzed. The calculation results show that the maximum stress is located at the edges of the gear teeth for the different contact positions. When the teeth are loaded with the repeated large stress, cracks are produced at the tooth edges at first and then are growing. The tooth breakage is produced at last. Gear chamfers using two circulars at the tooth edges can change the location of the maximum stress and the maximum MISES stress can be reduced by 20% or more. Therefore, the fracture problem of gear teeth is solved basically.

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Static/Dynamic Contact Finite Element Analysis for Tooth Profile Modification of Helical Gears

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.86.384 ◽

2011 ◽

Vol 86 ◽

pp. 384-388

Author(s):

Yong Jun Wu ◽

Jian Jun Wang ◽

Qin Kai Han

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Vibration Reduction ◽

Dynamic Contact ◽

Tooth Profile ◽

Element Analysis ◽

Helical Gears ◽

Profile Modification ◽

Tooth Profile Modification ◽

Static Contact

A precise approach for the tooth profile modification (TPM) of helical gear is presented in the paper based on the static contact finite element analysis (FEA). The high-precision finite element model of helical meshing gear pairs is established. The type and amount of TPM are accurately determined by the static contact FEA results. The dynamic contact simulations of helical gears with and without tooth modification are investigated to estimate the vibration reduction effect of the TPM. Moreover the numerical simulations are compared with the experimental results. Both results show that the proposed precise TPM of helical gears is effective on vibration reduction around the working load, and the dynamic contact simulation is effective on estimating the vibration reduction influence of the TPM.

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Finite element models predict in vitro vertebral body compressive strength better than quantitative computed tomography

Bone ◽

10.1016/s8756-3282(03)00210-2 ◽

2003 ◽

Vol 33 (4) ◽

pp. 744-750 ◽

Cited By ~ 373

Author(s):

R.Paul Crawford ◽

Christopher E. Cann ◽

Tony M. Keaveny

Keyword(s):

Computed Tomography ◽

Finite Element ◽

Compressive Strength ◽

Vertebral Body ◽

Quantitative Computed Tomography ◽

Finite Element Models ◽

Better Than

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PARAMETRIC STUDIES ON THE COMPONENT-BASED APPROACH TO MODELLING BEAM BOTTOM FLANGE BUCKLING AT ELEVATED TEMPERATURES

Acta Polytechnica ◽

10.14311/ap.2016.56.0132 ◽

2016 ◽

Vol 56 (2) ◽

pp. 132

Author(s):

Guan Quan ◽

Shan-Shan Huang ◽

Ian Burgess

Keyword(s):

Finite Element ◽

Analytical Model ◽

Elevated Temperatures ◽

Finite Element Models ◽

Bottom Flange ◽

Class 1 ◽

Shear Buckling ◽

Post Buckling ◽

Parametric Studies ◽

Better Than

<p>In this study, an analytical model of the combination of beam-web shear buckling and bottom-flange buckling at elevated temperatures has been introduced. This analytical model is able to track the force-deflection path during post-buckling. A range of 3D finite element models has been created using the ABAQUS software. Comparisons have been carried out between the proposed analytical model, finite element modelling and an existing theoretical model by Dharma (2007). Comparisons indicate that the proposed method is able to provide accurate predictions for Class 1 and Class 2 beams, and performs better than the existing Dharma model, especially for beams with high flange-to-web thickness ratios. A component-based model has been created on the basis of the analytical model, and will in due course be implemented in the software Vulcan for global structural fire analysis.</p>

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How does tooth cusp radius of curvature affect brittle food item processing?

Journal of The Royal Society Interface ◽

10.1098/rsif.2013.0240 ◽

2013 ◽

Vol 10 (84) ◽

pp. 20130240 ◽

Cited By ~ 20

Author(s):

Michael A. Berthaume ◽

Elizabeth R. Dumont ◽

Laurie R. Godfrey ◽

Ian R. Grosse

Keyword(s):

Finite Element ◽

Food Item ◽

Sampling Method ◽

High Stress ◽

Radius Of Curvature ◽

Finite Element Models ◽

Partial Support ◽

Stress Concentrations ◽

Food Items ◽

Better Than

Tooth cusp sharpness, measured by radius of curvature (RoC), has been predicted to play a significant role in brittle/hard food item fracture. Here, we set out to test three existing hypotheses about this relationship: namely, the Blunt and Strong Cusp hypotheses, which predict that dull cusps will be most efficient at brittle food item fracture, and the Pointed Cusp hypothesis, which predicts that sharp cusps will be most efficient at brittle food item fracture using a four cusp bunodont molar. We also put forth and test the newly constructed Complex Cusp hypothesis, which predicts that a mixture of dull and sharp cusps will be most efficient at brittle food item fracture. We tested the four hypotheses using finite-element models of four cusped, bunodont molars. When testing the three existing hypotheses, we assumed all cusps had the same level of sharpness (RoC), and gained partial support for the Blunt Cusp hypotheses. We found no support for the Pointed Cusp or Strong Cusp hypotheses. We used the Taguchi sampling method to test the Complex Cusps hypothesis with a morphospace created by independently varying the radii of curvature of the four cusps in the buccolingual and mesiodistal directions. The optimal occlusal morphology for fracturing brittle food items consists of a combination of sharp and dull cusps, which creates high stress concentrations in the food item while stabilizing the food item and keeping the stress concentrations in the enamel low. This model performed better than the Blunt Cusp hypothesis, suggesting a role for optimality in the evolution of cusp form.

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Finite element generalized tooth contact analysis of double circular arc helical gears

STRUCTURAL ENGINEERING AND MECHANICS ◽

10.12989/sem.2012.43.4.439 ◽

2012 ◽

Vol 43 (4) ◽

pp. 439-448 ◽

Cited By ~ 3

Author(s):

Wentao Qu ◽

Xiongqi Peng ◽

Ning Zhao ◽

Hui Guo

Keyword(s):

Finite Element ◽

Contact Analysis ◽

Tooth Contact Analysis ◽

Tooth Contact ◽

Circular Arc ◽

Helical Gears

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Study on Numerical Simulation of Projectile Penetrating UHMWPE Fiber Layers and Effects of Projectile Parameters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.630.121 ◽

2012 ◽

Vol 630 ◽

pp. 121-126

Author(s):

Gong Wu Huang ◽

Ai Jun Chen ◽

Shao Min Luo ◽

Cheng Xu

Keyword(s):

Numerical Simulation ◽

Finite Element ◽

High Speed ◽

Research Approach ◽

Finite Element Models ◽

Uhmwpe Fiber ◽

Penetration Ability ◽

The Relationship ◽

Better Than ◽

Good Agreement

Finite element models of bullet penetrating UHMWPE fiber layers are established to study the relationship between parameters of projectile and penetration ability using LS-DYNA software. The numerical simulation results of penetration calculated in Lagrange algorithm are in good agreement with the real experimental results, which verify the validity of the finite element models and algorithm. The numerical results show that high speed and small angle of attack can improve the penetration ability, the penetration ability of oval projectile is better than flat head projectile. A valid and reliable research approach for evaluating the design of protective equipment and efficiency of projectiles are proposed.

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