Academic literature on the topic 'Gear tooth Computational Model'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Gear tooth Computational Model.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Gear tooth Computational Model"
1
Glodež, Srečko, and Marko Šori. "Bending Fatigue Analysis of PM Gears." Key Engineering Materials 754 (September 2017): 299–302. http://dx.doi.org/10.4028/www.scientific.net/kem.754.299.
Full textAbstract:
The paper discusses the computational and experimental approach for determination of the PM gears service life concerning bending fatigue in a gear tooth root. A proposed computational model is based on the stress-life approach where the stress field in a gear tooth root is determined numerically using FEM. The experimental procedure was done on a custom made back-to-back gear testing rig. The comparison between computational and experimental results has shown that the proposed computational approach is appropriate calculation method for service life estimation of sintered gears regarding tooth root strength. Namely, it was shown that in the case of proper heat treatment of tested gears, the tooth breakage occurred inside the interval with 95 % probability of failure, which has been determined using proposed computational model.
2
Portron, Stéphane, Philippe Velex, and Vincent Abousleiman. "A hybrid model to study the effect of tooth lead modifications on the dynamic behavior of double helical planetary gears." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 21-22 (May 1, 2019): 7224–35. http://dx.doi.org/10.1177/0954406219846156.
Full textAbstract:
In this paper, a hybrid model is used to investigate the dynamic behavior of planetary gears. Sun-gear, planets, and ring-gear are modeled using lumped parameters elements, while planet carrier is integrated via a condensed finite element model. This approach intends to be more precise than the traditional lumped parameter models while keeping acceptable computational times. In some aeronautical applications, tooth lead modifications can be necessary to counterbalance the effect of planet carrier deflections on tooth load distribution. This study focuses on the influence of various lead modifications on the dynamic behavior of double helical planetary gears over a broad range of loads.
3
Liu, Yanping, Yongqiang Zhao, Ming Liu, and Xiaoyu Sun. "Parameterized High-Precision Finite Element Modelling Method of 3D Helical Gears with Contact Zone Refinement." Shock and Vibration 2019 (July 7, 2019): 1–17. http://dx.doi.org/10.1155/2019/5809164.
Full textAbstract:
In order to perform a tooth contact analysis of helical gears with satisfactory accuracy and computational time consuming, a parameterized approach to establish a high-precision three-dimension (3D) finite element model (FEM) of involute helical gears is proposed. The enveloping theory and dentiform normal method are applied to deduce the mathematical representations of the root transit curve as well as the tooth profile of the external gear in the transverse plane based on the manufacturing process. A bottom-up modelling method is applied to build the FEM of the helical gear directly without the intervention of CAD software or creating the geometry model in advance. Local refinement methodology of the hexahedral element has been developed to improve the mesh quality and accuracy. A computer program is developed to establish 3D helical gear FEM with contact region well refined with any parameters and mesh density automatically. The comparison of tooth contact analysis between the coarse-mesh model and local refinement model demonstrates that the present method can efficiently improve the simulation accuracy while greatly reduce the computing cost. Using the proposed model, the tooth load sharing ratio, static transmission error, meshing stiffness, root bending stress, and contact stress of the helical gear are obtained based on the quasistatic load tooth contact analysis. This methodology can also be used to create other types of involute gears, such as high contact ratio gear, involute helical gears with crossed axes, or spiral bevel gears.
4
Zorko, Damijan, Jože Duhovnik, and Jože Tavčar. "Tooth bending strength of gears with a progressive curved path of contact." Journal of Computational Design and Engineering 8, no. 4 (June 18, 2021): 1037–58. http://dx.doi.org/10.1093/jcde/qwab031.
Full textAbstract:
Abstract The article presents a comprehensive study on the tooth bending strength of spur gears with a progressive curved path of contact, or so-called S-gears. Systematic gear meshing simulations were conducted to study the effects of S-gear geometry parameters on tooth bending strength. Different S-gear geometries were analysed in a systematically organized manner, and a comparison was made against a standard 20° pressure angle involute shape. Furthermore, different material combinations, e.g. polymer/polymer, steel/polymer, and steel/steel, of both drive and driven gear were analysed within a meaningful range of loads. The gear profile shape, material combination of the drive and the driven gear, and the transmitted load were found as the main parameters affecting gear tooth bending stress. Complex, non-linear relations between the recognized effects and the corresponding root stress were observed. Based on the numerical results, a shape factor, which considers the above-mentioned effects, was introduced, and a model for root strength control of S-gears was proposed and verified employing the finite element method (FEM).
5
Kahraman, A., P. Bajpai, and N. E. Anderson. "Influence of Tooth Profile Deviations on Helical Gear Wear." Journal of Mechanical Design 127, no. 4 (October 5, 2004): 656–63. http://dx.doi.org/10.1115/1.1899688.
Full textAbstract:
In this study, a surface wear prediction model for helical gears pairs is employed to investigate the influence of tooth profile deviations in the form of intentional tooth profile modifications or manufacturing errors on gear tooth surface wear. The wear model combines a finite-element-based gear contact mechanics model that predicts contact pressures, a sliding distance computation algorithm, and Archard’s wear formulation to predict wear of the contacting tooth surfaces. Typical helical gear tooth modifications are parameterized by an involute crown, a lead crown, and an involute slope. The influence of these parameters on surface wear are studied within typical tolerance ranges achievable using hob/shave process. The results indicate that wear is related to the combined modification parameters of a gear pair rather than individual gear parameters. At the end, a design formula is proposed that relates the mismatch of contacting surface slopes to the maximum initial wear rate.
6
Lu, Fengxia, Meng Wang, Wenbin Pan, Heyun Bao, and Wenchang Ge. "CFD-Based Investigation of Lubrication and Temperature Characteristics of an Intermediate Gearbox with Splash Lubrication." Applied Sciences 11, no. 1 (December 31, 2020): 352. http://dx.doi.org/10.3390/app11010352.
Full textAbstract:
In this study, we propose a computational fluid dynamics (CFD)-based method to study the lubrication and temperature characteristics of an intermediate gearbox with splash lubrication. A volume of fluid (VOF) multiphase model was used to track the interface between oil and air. A multiple reference frame (MRF) model was adopted to accurately simulate the movement characteristics of the gears, bearings, and the surrounding flow field. The thermal-fluid coupling computational model of an intermediate gearbox with splash lubrication was then established. Combined with experimental results, we verified that the lubricating oil temperature was below the limit requirement (<110 °C). The numerical results revealed that large amounts of lubricating oil were splashed onto the tooth surfaces near the gear meshing area. A large convective heat transfer coefficient corresponds to a low gear tooth surface temperature. The tooth surface temperature of the driving gear is higher than that of the driven gear. The distribution law of oil volume fraction of the bearing roller was jointly affected by the roller rotation direction and gravity. The convective heat transfer coefficient of the roller wall was largely related to the lubrication environment of the roller, including the oil distribution inside the bearing cavity and the flow rate.
7
Ji, Hongchao, Jianwei Dong, Weichi Pei, Haiyang Long, and Jing Chu. "Solution of Spur Gear Meshing Stiffness and Analysis of Degradation Characteristics." Mechanics 26, no. 2 (April 20, 2020): 153–60. http://dx.doi.org/10.5755/j01.mech.26.2.23270.
Full textAbstract:
The computational model of spur gear meshing stiffness is established by using the hypothesis of cantilever beam of the gear. The meshing stiffness of spur gear is calculated by analytical method, and the distributional curve of meshing stiffness is obtained by comparison with FEM. Experimental verification of simulated results is performed by mechanical test-bed of closed flow. The experimental results show that the simulation results are in good agreement with the experimental results. Based on the FEM models of gear tooth with cracks of different lengths, the comparison between degradation trends in different meshing regions that shows that the degree of degradation in a single tooth meshing area is much higher than in a double teeth meshing region. In the FEM models of gear tooth with cracks of different lengths, the stiffness degradation rate of the double tooth indentation area increases first and then decreases, and the crack length is most obvious between 4 and 8 mm.
8
Bo, Shen Yun, Xuan Liu, and Li Jun Wang. "Design of double-crowned tooth geometry for spiroid gear produced by precision casting process." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, no. 6 (September 8, 2016): 1021–30. http://dx.doi.org/10.1177/0954405416661003.
Full textAbstract:
A novel double-crowned tooth geometry is proposed by the application of ease-off topography for spiroid gear manufactured by precision casting process, with the goals of localizing the bearing contact and obtaining a perfect function of transmission errors. The modified tooth surface is applied as the reference geometry to machine the die cavity geometry that will produce such geometry of the gears. The tooth geometry of crowned gear was achieved first from a pre-designed controllable function of transmission errors along the desired contact path. Then, the desired ease-off topography along the contact line is designed and calculated computationally from the given mathematic model of surface modification. The geometry of double-crowned spiroid gear could be reconstructed by superimposing the ease off of contact line direction on the profile-crowned tooth surface. The article provides numerical examples to validate the feasibility of ease-off modification methodology that was used to produce the double-crowned tooth geometry for the gears, while tooth contact analysis is performed computationally to investigate the stability of bearing contact and function of transmission errors to alignment.
9
Zhao, Ning, and Qing Jian Jia. "Research on Windage Power Loss of Spur Gear Base on CFD." Applied Mechanics and Materials 184-185 (June 2012): 450–55. http://dx.doi.org/10.4028/www.scientific.net/amm.184-185.450.
Full textAbstract:
The paper established three-dimensional Computational fluid dynamic (CFD) model of the oil-air mixture in the gearbox after meshing by ICEM CFD simulated the turbulence model by the CFD. The method of calculate the windage power loss (WPL) of the spur gear were put forward. In order to reduced the WPL, compared the results between the CFD model with different modulus、clearance of the shroud and radius of the modification of gear top. The modulus is major parameter to WPL; the gear with shroud have lower WPL , WPL of the tooth flank and clearance of the tooth flank shroud do not show the proportional relationship, the gear with smallest clearance of gear side have lowest WPL，the modification of gear top can reduce the eddy scale which can reduce the WPL.
10
Liu, Xinrong, and Zhonghou Wang. "Analysis of Contact Part of Error Tooth Surface and Dynamic Performance Prediction for Involute Gear." Mathematical Problems in Engineering 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/6143054.
Full textAbstract:
Aiming at the problem of constructing digital model of involute gear with error, the method of linear interpolation combined with area weight interpolation is proposed. Based on the non-feature discrete data block technique, the true tooth surface discrete data obtained by the coordinate measuring instrument is divided into blocks, and then the interpolation method is used to interpolate the nonmeasurement area to construct the real tooth surface with errors. The contact part and dynamic performance of the gear are predicted by using the constructed error tooth surface. The contact error of the tooth surface and the transmission error of the gear are verified by the test, and the reliability of the judgment result is judged by measuring the vibration in the direction of the gear meshing line. Compared with the example, this method not only reduces the computational complexity of the interpolation algorithm, but also improves the accuracy of the tooth interpolation data points and the smoothness of the error tooth surface.
Dissertations / Theses on the topic "Gear tooth Computational Model"
1
Pykal, Vojtěch. "Výpočtové modelování dynamiky záběru čelního ozubeného soukolí v prostředí MBS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-445163.
Full textAbstract:
This master’s thesis is focused on the compilation of a computational modelling of gear mesh engagement dynamics of a spur gear by MBS approach. The user input is the specific geometry of gears, the operating speed, and the load torque. The output are the forces in the gear engagement and the reaction of the forces in the wheel bearings depending on the change in the stiffness of the gear due to the changing number of teeth in the engagement and the change in the axial distance. This model is characterized by a fast and relatively accurate calculation in the time domain. This means that it can react to changes in parameters during simulation such as axial distance, speed, and torque.
2
Luo, Yang. "Dynamic Modelling and Fault Feature Analysis of Gear Tooth Pitting and Spalling." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38834.
Full textAbstract:
Fault feature analysis of gear tooth spall plays a vital role in gear fault diagnosis. Knowing the characteristic of fault features and their evolution as a gear tooth fault progresses is key to fault severity assessment. This thesis provides a comprehensive (both theoretical and experimental) analysis of the fault vibration features of a gear transmission with progressive localized gear tooth pitting and spalling. A dynamic model of a one-stage spur gear transmission is proposed to analyze the vibration behavior of a gear transmission with tooth fault. The proposed dynamic model considers the effects of Time Varying Mesh Stiffness (TVMS), tooth surface roughness changes and geometric deviations due to pitting and spalling, and also incorporates a time-varying load sharing ratio, as well as dynamic tooth contact friction forces, friction moments and dynamic mesh damping ratios. The gear dynamical model is validated by comparison with responses obtained from an experimental test rig under different load and fault conditions. In addition, several methods are proposed for the evaluation of the TVMS of a gear pair with tooth spall(s) with curved bottom and irregular shapes, which fills the current research gap on modelling tooth spalls with irregular shapes and randomly distribution conditions. Experiments are conducted and the fault vibration features and their evolution as the tooth fault progresses are analyzed. Based on feature analysis, a new health indicator is proposed to detect progressive localized tooth spall.
3
Dai, Xiang. "Nonlinear Dynamics and Vibration of Gear and Bearing Systems using A Finite Element/Contact Mechanics Model and A Hybrid Analytical-Computational Model." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/78861.
Full textAbstract:
This work investigates the dynamics and vibration in gear systems, including spur and helical gear pairs, idler gear trains, and planetary gears.
The spur gear pairs are analyzed using a finite element/contact mechanics (FE/CM) model.
A hybrid analytical-computational (HAC) model is proposed for nonlinear gear dynamics.
The HAC predictions are compared with FE/CM results and available experimental data for validation.
Chapter ref{{CH:GP_Strain}} investigates the static and dynamic tooth root strains in spur gear pairs using a finite element/contact mechanics approach.
Extensive comparisons with experiments, including those from the literature and new ones, confirm that the finite element/contact mechanics formulation accurately predicts the tooth root strains.
The model is then used to investigate the features of the tooth root strain curves as the gears rotate kinematically and the tooth contact conditions change.
Tooth profile modifications are shown to strongly affect the shape of the strain curve.
The effects of strain gage location on the shape of the static strain curves are investigated.
At non-resonant speeds the dynamic tooth root strain curves have similar shapes as the static strain curves.
At resonant speeds, however, the dynamic tooth root strain curves are drastically different because large amplitude vibration causes tooth contact loss.
There are three types of contact loss nonlinearities: incomplete tooth contact, total contact loss, and tooth skipping, and each of these has a unique strain curve.
Results show that different operating speeds with the same dynamic transmission error can have much different dynamic tooth strain.
Chapters ref{{CH:HAC_2DSingle}}, ref{{CH:HAC_2DMultiple}}, and ref{{CH:HAC_3DSingle}} develops a hybrid-analytical-computational (HAC) method for nonlinear dynamic response in gear systems.
Chapter ref{{CH:HAC_2DSingle}} describes the basic assumptions and procedures of the method, and implemented the method on two-dimensional vibrations in spur gear pairs.
Chapters ref{{CH:HAC_2DMultiple}} and ref{{CH:HAC_3DSingle}} extends the method to two-dimensional multi-mesh systems and three-dimensional single-mesh systems.
Chapter ref{{CH:HAC_2DSingle}} develops a hybrid analytical-computational (HAC) model for nonlinear dynamic response in spur gear pairs.
The HAC model is based on an underlying finite element code.
The gear translational and rotational vibrations are calculated analytically using a lumped parameter model, while the crucial dynamic mesh force is calculated using a force-deflection function that is generated from a series of static finite element analyses before the dynamic calculations.
Incomplete tooth contact and partial contact loss are captured by the static finite element analyses, and included in the force-deflection function.
Elastic deformations of the gear teeth, including the tooth root strains and contact stresses, are calculated.
Extensive comparisons with finite element calculations and available experiments validate the HAC model in predicting the dynamic response of spur gear pairs, including near resonant gear speeds when high amplitude vibrations are excited and contact loss occurs.
The HAC model is five orders of magnitude faster than the underlying finite element code with almost no loss of accuracy.
Chapter ref{{CH:HAC_2DMultiple}} investigates the in-plane motions in multi-mesh systems, including the idler chain systems and planetary gear systems, using the HAC method that introduced in Chap. ref{{CH:HAC_2DSingle}}.
The details of how to implement the HAC method into those systems are explained.
The force-deflection function for each mesh is generated individually from a series of static finite element analyses before the dynamic calculations.
These functions are used to calculated the dynamic mesh force in the analytical dynamic analyses.
The good agreement between the FE/CM and HAC results for both the idler chain and planetary gear systems confirms the capability of the HAC model in predicting the in-plane dynamic response for multi-mesh systems.
Conventional softening type contact loss nonlinearities are accurately predicted by HAC method for these multi-mesh systems.
Chapter ref{{CH:HAC_3DSingle}} investigates the three-dimensional nonlinear dynamic response in helical gear pairs.
The gear translational and rotational vibrations in the three-dimensional space are calculated using an analytical model, while the force due to contact is calculated using the force-deflection.
The force-deflection is generated individually from a series of static finite element analyses before the dynamic calculations.
The effect of twist angle on the gear tooth contact condition and dynamic response are included.
The elastic deformations of the gear teeth along the face-width direction are calculated, and validated by comparing with the FE/CM results.Ph. D.
4
Jouaud, Maxime. "Etude des interactions de la protéine PMP22 avec les intégrines dans la pathogénie de la maladie de Charcot-Marie-Tooth de type 1A." Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0096/document.
Full textAbstract:
Des modifications du gène PMP22 (Peripheral Myelin Protein 22) sont responsables de neuropathies du système nerveux périphérique : l’Hypersensibilité à la Pression (HNPP : Hereditary Neuropathy with liability to Pressure Palsy) lorsqu’il est délété, CMT1A (Charcot-Marie-Tooth type 1A) lorsqu’il est dupliqué et CMT1E ou HNPP lors de mutations ponctuelles. Cependant, le rôle de la protéine PMP22 dans ces neuropathies demeure obscur. Dans un premier temps, nous nous sommes intéressés aux partenaires d’interactions potentiels de PMP22 : l’intégrine α6β4 (un récepteur des laminines), pourrait être impliqué dans le CMT1A. Dans cette étude, nous avons utilisé un modèle de rat transgénique portant des copies supplémentaires de PMP22 de souris. Chez ce modèle, nous avons mis en évidence des variations d’expression génique des intégrines, ainsi qu’une mauvaise localisation cellulaire de celles-ci. Ces variations des niveaux d’expression des intégrines sont les témoins d’un retard de la maturation des cellules de Schwann myélinisantes, expliquant la diminution de l’épaisseur des gaines de myéline, observée chez les rats CMT1A. Dans un second temps, nous avons étudié le cas particulier d’un patient sans expression de PMP22, en raison de deux mutations composites sur les deux allèles de PMP22. Nous avons observé que l’absence de PMP22 chez l’homme entraine une absence complète de myéline due à un blocage de l’initialisation de la myélinisation lors de la formation du mésaxone. Dans un troisième temps, nous avons effectué une étude comparative de modèles animaux et de patients atteints de CMT1A / 1E et d’HNPP permettant de valider l’utilisation de tels modèles dans l’étude de ses neuropathies. Enfin, nous nous sommes intéressés d’un point de vue informatique à la structure tridimensionnelle de différentes protéines dont PMP22 grâce à la dynamique moléculaire. Ce modèle tridimensionnel de PMP22 est le point de départ de l’étude des mutations ponctuelles ainsi que des interactions de PMP22 avec son environnement. Grâce aux animaux modèles et à l’étude de patients, nous avons montré le rôle indispensable de PMP22 dans l’initialisation de la myélinisation ainsi que son effet sur les intégrines dans le CMT1A. L’utilisation de modèles informatiques tridimensionnels créés de PMP22 permettra de comprendre les effets des mutations ponctuelles sur sa structure, et ses interactionsInteractions study of PMP22 protein with integrins in Charcot-Marie-Tooth disease type 1A pathogenesisChanges in the PMP22 gene (Peripheral Myelin Protein 22) are responsible for peripheral nervous system neuropathies: Hereditary Neuropathy with liability to Pressure Palsy (HNPP) when PMP22 is deleted, Charcot Marie Tooth disease subtype 1A (CMT1A) when PMP22 is duplicated and CMT1E or HNPP when point mutations are present on the PMP22 gene. However, the PMP22 role in these neuropathies remains unclear. Firstly, we studied one of the PMP22 interaction partner: the α6β4 integrin (a laminin receptor), which could be involved in the CMT1A. During this study, we used a transgenic rat model carrying supplementary copies of PMP22 gene from mouse. With this model, we showed variations of expression of integrins genes and a mislocalization of integrins proteins. These variations of integrins witnesses a delay in myelinating Schwann cells maturation, explaining the reduction of myelin sheath thickness observed on CMT1A rats. In a second time, we studied the case of a patient without PMP22 expression, carrying compound mutations one the two alleles of PMP22. We showed that the lack of PMP22 on human leads to a complete lack of myelin due to a blocking in mesaxon formation. In a third time, we conducted a comparative study of animal models and patients with CMT1A / 1E and HNPP. This study allows us to validate the use of such models in the study of neuropathies. Finally, thanks to computational tools we studied the three-dimensional structure of different protein, including PMP22 by using molecular dynamics. This three-dimensional model is the starting point of point mutations study as well as PMP22 interactions with its environments. With animal models and through the study of patients, we have demonstrated the indispensable role of PMP22 in myelin initiation as well as, its effect on integrins expression in CMT1A. The use of PMP22 three-dimensional computational model will help us to understand effects of point mutation on PMP22 structure and interactions
5
Czakó, Alexander. "Stanovení chyby převodu u čelního ozubení s šikmými zuby." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-433537.
Full textAbstract:
This diploma thesis primarily deals with the transmission error issue which is one of the dominant sources of vibration in gear pairs and transmission systems. The vibrations subsequently generate noise which is often subjected to increasingly stricter demands across the industry, including the automotive one. It turns out that reducing the peak-to-peak value of the transmission error has a beneficial effect on the vibro-acoustic properties of gears and gear pairs. This thesis aims to determine the transmission error under static conditions, since a gear pair with a low static transmission error is a good assumption for a low transmission error even under dynamic effects. The resulting values of the transmission error can be influenced already during the design of the gear macro-geometry. It is also suitable to apply micro-geometric adjustments – modifications to the gear teeth. For this reason, the search part of the thesis is dedicated to theoretical knowledge, especially concerning the geometry of gears, modifications of teeth and the overall transmission error and its determination. The transmission error can be determined in several ways, including a technical experiment. However, due to time and financial reasons, this is not always possible, and therefore, the possibility of using numerical simulations is offered. In this thesis, the approach using stress-strain quasi-static contact analysis using the finite element method in Ansys Workbench software is used. The advantage is, among other things, a good comparability of results. The input to the FEM analysis is 3D CAD geometry – in this case, it is specifically a helical gear pair with parallel axes. The model/assembly of this gear pair is created in PTC Creo software fully parametrically, so it is possible to generate arbitrary gear pair configurations by changing the input parameters, which significantly saves time. At the end of this diploma thesis, the stress-strain analysis of various gear configurations is evaluated, with respect to the equivalent stress and contact pressure. Furthermore, the static transmission error – its graphs and peak-to-peak values – is determined from FEM analyses for different gear geometry, including tooth modifications, and for various loading torques. Last but not least, the effects of contact/overlap ratio and centre distance are evaluated.
6
Chen, Kuan-Hun, and 陳冠宏. "Study on Mathematic Model of the Cutting Edge on the Multi-start Hob And Analysis on the Tooth Profile Errors of the Hobbed Gear." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/51186635221618733660.
Full textAbstract:
碩士國立中正大學
機械系
93
Hobbing is one of the most efficient and economic ways to produce spur and helical gears. Besides the setting of the hobbing machine, the geometric parameters of the hob and the feeds of the hobbing machine greatly effects the precision of the hobbed gear. This thesis aims to set up mathematical model for the cutting edge of multi-start hob and the surface topology of the hobbed gear. By varying the geometric parameters of the hob and the hobbing feeds , the precision and the surface roughness of the hobbed gear are investigated. The results of this thesis can be used to simulate the cutting mark on the toothsurface of the hobbed gear and calculate the tooth flank precision of the hobbed gear.
Book chapters on the topic "Gear tooth Computational Model"
1
Yang, Shenghua. "The Fracture Process Simulation of the Gear Tooth and the Advance of Computational Fracture Mechanics." In Computational Mechanics, 225. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-75999-7_25.
Full text
2
Sommer, Andrew, Jim Meagher, and Xi Wu. "An Advanced Numerical Model of Gear Tooth Loading from Backlash and Profile Errors." In Rotating Machinery, Structural Health Monitoring, Shock and Vibration, Volume 5, 191–201. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-9428-8_15.
Full text
3
Inalpolat, Murat. "A Computational Model to Investigate the Influence of Spacing Errors on Spur Gear Pair Dynamics." In Experimental Techniques, Rotating Machinery, and Acoustics, Volume 8, 1–10. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-15236-3_1.
Full text
4
Diestmann, Thomas, Nils Broedling, Benedict Götz, and Tobias Melz. "Surrogate Model-Based Uncertainty Quantification for a Helical Gear Pair." In Lecture Notes in Mechanical Engineering, 191–207. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77256-7_16.
Full textAbstract:
AbstractCompetitive industrial transmission systems must perform most efficiently with reference to complex requirements and conflicting key performance indicators. This design challenge translates into a high-dimensional multi-objective optimization problem that requires complex algorithms and evaluation of computationally expensive simulations to predict physical system behavior and design robustness. Crucial for the design decision-making process is the characterization, ranking, and quantification of relevant sources of uncertainties. However, due to the strict time limits of product development loops, the overall computational burden of uncertainty quantification (UQ) may even drive state-of-the-art parallel computing resources to their limits. Efficient machine learning (ML) tools and techniques emphasizing high-fidelity simulation data-driven training will play a fundamental role in enabling UQ in the early-stage development phase.This investigation surveys UQ methods with a focus on noise, vibration, and harshness (NVH) characteristics of transmission systems. Quasi-static 3D contact dynamic simulations are performed to evaluate the static transmission error (TE) of meshing gear pairs under different loading and boundary conditions. TE indicates NVH excitation and is typically used as an objective function in the early-stage design process. The limited system size allows large-scale design of experiments (DoE) and enables numerical studies of various UQ sampling and modeling techniques where the design parameters are treated as random variables associated with tolerances from manufacturing and assembly processes. The model accuracy of generalized polynomial chaos expansion (gPC) and Gaussian process regression (GPR) is evaluated and compared. The results of the methods are discussed to conclude efficient and scalable solution procedures for robust design optimization.
5
"Tooth Model in Orthodontics and Prosthodontics." In Computational Biomechanics of the Musculoskeletal System, 271–86. CRC Press, 2014. http://dx.doi.org/10.1201/b17439-30.
Full text
6
Dwyer-Joyce, R., J. C. Hamer, J. M. Hutchinson, E. Ionannides, and R. S. Sayles. "Paper XIV (ii) A Pitting Fatigue Model for Gear Tooth Contacts." In Vehicle Tribology, 391–400. Elsevier, 1991. http://dx.doi.org/10.1016/s0167-8922(08)70156-1.
Full text
7
Hongu, J., H. Noborio, T. Koide, and A. Tamura. "Proposal of linear mapping model among machining processes for gear tooth surface using graphic analysis." In International Conference on Gears 2019, 1199–206. VDI Verlag, 2019. http://dx.doi.org/10.51202/9783181023556-1199.
Full text
8
Boiadjiev, I., J. Witzig, T. Tobie, and K. Stahl. "Tooth flank fracture – basic principles and calculation model for a sub surface initiated fatigue failure mode of case hardened gears." In International Gear Conference 2014: 26th–28th August 2014, Lyon, 670–80. Elsevier, 2014. http://dx.doi.org/10.1533/9781782421955.670.
Full text
9
Rauch, A. D., and C. Wirth. "An easy-to-use and fast computational model for the prediction of the influence of manufacturing errors on gear transmission error." In International Conference on Gears 2019, 645–56. VDI Verlag, 2019. http://dx.doi.org/10.51202/9783181023556-645.
Full textConference papers on the topic "Gear tooth Computational Model"
1
Eritenel, Tugan, and Robert G. Parker. "Computational Nonlinear Vibration Analysis of Gear Pairs Using a Three-Dimensional Model." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-87485.
Full textAbstract:
This work investigates the nonlinear vibration of gear pairs, where the nonlinearity is due to portions of gear teeth contact lines losing contact (partial contact loss). The gears are modeled as rigid bodies that admit motion in six degrees of freedom. A network of distributed stiffnesses models the nonlinear gear contact. The distributed stiffness scheme is obtained by discretizing the kinematic contact lines into segments, each with the possibility of losing contact. Whether these segments are actually in contact or not is determined by the gear deflections and tooth modifications. The modeling is verified with finite element analysis and experimental measurements from the literature. The combination of a translational and a tilting spring is proven to be identical to the distributed stiffness model. This equivalent representation of the mesh identifies a nonlinear tilting mesh stiffness that accompanies the well-known translational gear mesh stiffness typically modeled by a single spring. Modal analysis reveals a mesh tilting vibration mode where this spring dominates, in addition to the mesh deflection vibration mode. Computational dynamic analysis of a helical gear pair near the natural frequencies of the mesh tilting and deflection modes exhibit nonlinear vibrations. Both cases involve nonlinearity due to partial contact loss where only part of a nominal contact line loses contact at an instant.
2
Oja, Michael E., Carlos H. Wink, Nikhil Deo, Robert L. McDaniels, Robert G. Tryon, Animesh Dey, and Sanjeev M. Kulkarni. "Gear Tooth Bending Fatigue Life Prediction Using Integrated Computational Material Engineering." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-67911.
Full textAbstract:
The paper presents a computational method to predict the cyclic life of gears subjected to single tooth bending fatigue, using VEXTEC’s VPS-MICRO® software. The project was a collaborative effort between Eaton - Vehicle Group and VEXTEC Corporation to replicate physical testing virtually, more specifically to virtually determine bending fatigue curves of gears made from different steels. VPS-MICRO is based on VEXTEC’s patented Virtual Life Management® (VLM®) technology which includes computational microstructural damage models to simulate the fatigue performance and calculate the lifetime of various product configurations. The framework probabilistically estimates the fatigue behavior of a range of Eaton gears and other products.
3
Osakue, Edward E., and Lucky Anetor. "A Method for Constructing Standard Involute Gear Tooth Profile." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86573.
Full textAbstract:
A simple but accurate combined computationaland graphical method for creating drawings and solid models of standard involute gears is presented. The method is predicated on the fact that the gear tooth angle at the base circle is fixed for a gear of specified module or size. As the contact point moves along the involute curve from the base circle point through the pitch point to the addendum circle point; the involute and gear tooth contact angles change continuously but their sum is fixed at the value it was at the base circle. This allows the coordinates of points on the involute curve to be generated analytically without employing the roll angle as current available methods. The generated data can be implemented in any computer design drafting (CDD) package platform to create an accurate gear tooth profile. The computations are done with Microsoft Excel which generates the graphical data for the gear tooth profile that are used in the CDD package. The required inputs to the Excel spreadsheet are the gear module size, the pressure angle, the number of teeth and the radial number of steps. A gearset example is considered and created with this method. The solid model of the example gearset in mesh and 2D drawing of the pinion are presented.
4
Jelaska, Damir T., Srdjan Podrug, and Srecko Glodez. "Comparison of Numerical Models for Gear Tooth Root Fatigue Assessments." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79891.
Full textAbstract:
A several kinds of numerical models, including moving force model, for determination the service life of gears in regard to bending fatigue in a gear tooth root, is presented. The critical plane damage model, Socie and Bannantine [1], 1988, has been used to determine the number of stress cycles required for the fatigue crack initiation. This method determines also the initiated crack direction, what is good base for a further analyses of the crack propagation and the assessment of the total fatigue life. Finite element method and linear elastic fracture mechanics theories are then used for the further simulation of the fatigue crack growth under a moving load. Moving load produces a non-proportional load history in a gear’s tooth root. An approach that accounts for fatigue crack closure effects is developed to propagate crack under non-proportional load. Although some influences (non-homogeneous material, traveling of dislocations, etc.) were not taken into account in the computational simulations, the presented model seems to be very suitable for determination of service life of gears because numerical procedures used here are much faster and cheaper if compared with the experimental testing. The computational results are compared with other researchers’ numerical results and with service lives of real gears. The fatigue lives and crack paths determined in this paper exhibits a substantial agreement with experimental results and significant improvement compared with the existing numerical models.
5
Jelaska, Damir T., and Srdjan Podrug. "Gear Tooth Root Fatigue Assessments by Estimating the Real Stress Cycle." In ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-34233.
Full textAbstract:
A several kinds of numerical models, including moving force model, for determination the service life of gears in regard to bending fatigue in a gear tooth root, is presented. Finite element method and linear elastic fracture mechanics theories are then used for the further simulation of the fatigue crack growth under a moving load. Moving load produces a non-proportional load history in a gear’s tooth root. The corresponding stress cycle is obtained which enables more precise computing. An approach that accounts for fatigue crack closure effects is developed to propagate crack under non-proportional load. The computational results are compared with other researchers’ numerical results and with service lives of real gears. The fatigue lives and crack paths determined in this paper exhibits a substantial agreement with experimental results and significant improvement compared with the existing numerical models.
6
Jelaska, Damir T., Srecko Glodez, and Srdjan Podrug. "Numerical Modelling of the Crack Propagation Path at Gear Tooth Root." In ASME 2003 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/detc2003/ptg-48026.
Full textAbstract:
A numerical model for determination of service life of gears in regard to bending fatigue in a gear tooth root is presented. The Coffin-Manson relationship is used to determine the number of stress cycles Ni required for the fatigue crack initiation, where it is assumed that the initial crack is located at the point of the largest stresses in a gear tooth root. The simply Paris equation is then used for the further simulation of the fatigue crack growth, where required material parameters have been determined previously by the appropriate test specimens. The functional relationship between the stress intensity factor and crack length K = f(a), which is needed for determination of the required number of loading cycles Np for a crack propagation from the initial to the critical length, is obtained numerically. The total number of stress cycles N for the final failure to occur is then a sum N = Ni + Np. Although some influences were not taken into account in the computational simulations, the presented model seems to be very suitable for determination of service life of gears because numerical procedures used here are much faster and cheaper if compared with the experimental testing.
7
Parker, R. G., S. M. Vijayakar, and T. Imajou. "Modeling the Nonlinear Vibration of a Spur Gear Pair." In ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/ptg-14434.
Full textAbstract:
Abstract The dynamic response of a spur gear pair is investigated using a finite element/contact mechanics model that offers significant advantages for dynamic gear analyses. The gear pair is analyzed across a wide range of operating speeds and torques. Comparisons are made to other researchers’ published experiments that reveal complex nonlinear phenomena. The nonlinearity source is contact loss of the meshing teeth, which, in contrast to the prevailing understanding, occurs even for large torques despite use of high-precision gears. A primary feature of the modeling is that dynamic mesh forces are calculated using detailed contact analysis at each time step as the gears roll through mesh; there is no need to externally specify the excitation in the form of time-varying mesh stiffness, static transmission error input, or the like. A semi-analytical model near the tooth surface is matched to a finite element solution away from the tooth surface, and the computational efficiency that results permits dynamic analysis. Two single degree of freedom models are discussed briefly. While one gives encouragingly good results, the second, which appears to have better mesh stiffness modeling, gives poor comparisons with experiments. The results indicate the sensitivity of such models to changing mesh stiffness representations.
8
Al, Baydu C., Kathy Simmons, and Hervé P. Morvan. "Two-Phase Computational Modelling of a Spiral Bevel Gear Using a Eulerian Multiphase Model." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43541.
Full textAbstract:
The efficiency of power transmission systems is increasingly targeted with a view to reducing parasitic losses and improving specific fuel consumption (SFC). One of the effects associated with such parasitic losses is gear windage power loss and this mechanism can be a significant contributor to overall heat-to-oil within large civil aeroengines. The University of Nottingham Technology Centre in Gas Turbine Transmission Systems has been conducting experimental and computational research into spiral bevel gear windage applicable to an aeroengine internal gearbox (IGB). The two-phase flows related to gear lubrication, shrouding and scavenging are complex. Good understanding of such flows can be used to balance lubrication needs with need to minimise oil volumes and parasitic losses. Previous computational investigations have primarily employed discrete phase modelling (DPM) to predict oil behaviour under the shroud [1, 2]. In this paper modelling capability has been investigated and extended through application of FLUENT’s Eulerian multiphase model. In addition, DPM modelling linked to FLUENT’s Lagrangian film model has been conducted. A control volume with periodic symmetry comprising a single tooth passage of the bevel gear has been modelled to keep the computational cost down.The results from both models are compared to each other and to available experimental visual data. Both models are found to perform acceptably with the Eulerian multiphase model yielding results closer to those observed experimentally. The use of DPM with a Eulerian film model is suggested for future work and extension to a full 360° model is recommended.
9
Webb, Thomas, Carol Eastwick, and Herve´ Morvan. "Parametric Modelling of a Spiral Bevel Gear Using CFD." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22632.
Full textAbstract:
Initial results investigating windage power loss on a rotating shrouded spiral bevel gear using a parametric solid model and Computational Fluid Dynamics (CFD) are presented. The context behind this study is a desire to use CFD as a tool to investigate heat-to-oil within gas turbine bearing chambers and gearboxes in order to reduce costly rig-based experiments. This paper contains the methodology for creation of the parametric model of a spiral bevel gear in Pro/Engineer, formulation of a mesh in ICEM CFD and the subsequent CFD analysis in Fluent 6.2.26 and 12.0.16. A single tooth segment of a 91 teethed spiral bevel gear is produced with periodic boundaries imposed to reduce computational cost. Validation against experimental results for a single control gear is shown with particularly good correlation between static pressure rise across the face of the gear. Mesh verification is also presented. Using the model to change the module of the gear (effectively the number of teeth), investigations show that windage power loss reduces when the number of teeth increases. Analysis of the static pressure variation throughout the domain shows that all gears tested exhibit a linearly increasing relationship between non-dimensional mass-flow-rate and the pressure drop through the shroud restriction. The control gear was seen to have only a weak increase in static pressure gain across the gear tooth as the mass-flow-rate increases; however, a far larger increase exists for the module cases tested — at comparable mass-flow-rates to the control gear. As the number of teeth increase, the pressure gain across the gear reduces, and vice-versa. It is this difference between the gears that results in dissimilar windage power losses.
10
Heisler, Aaron S., John J. Moskwa, and Frank J. Fronczak. "Simulated Helical Gear Pump Analysis Using a New CFD Approach." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78472.
Full textAbstract:
The purpose of this paper is to focus on cavitation prediction at high-speeds in helical gear pumps for the purpose of hydrostatic dynamometer system development. Details of the fluid motion will be described through various stages of fluid transfer from the pump inlet to the outlet using various mesh densities. Using the results of these simulations, a discussion of design improvements for high-speed hydrostatic dynamometer operation is included. Conducting CFD simulations on external gear pumps is a difficult problem depending upon the complexity of the individual components. Simulating helical gears is especially taxing due to the complexity of the gear tooth profile. The additional detail in a helical gear pump model leads to an increase of the required mesh density and therefore increased computation time. A less computationally complex approach to simulating helical gears is to consider a helical gear as a series of thin spur gears rotated according to a predetermined helix angle. Details of this approach and results are discussed in this paper.