A Static and Dynamic Model of Geared Transmissions by Combining Substructures and Elastic Foundations—Applications to Thin-Rimmed Gears

2006 ◽  
Vol 129 (2) ◽  
pp. 184-194 ◽  
Author(s):  
M. N. Bettaïeb ◽  
P. Velex ◽  
M. Ajmi

The present work is aimed at predicting the static and dynamic behavior of geared transmissions comprising flexible components. The proposed model adopts a hybrid approach, combining classical beam elements, elastic foundations for the simulation of tooth contacts, and substructures derived from three-dimensional (3D) finite element grids for thin-rimmed gears and their supporting shafts. The pinion shaft and body are modeled via beam elements which simulate bending, torsion and traction. Tooth contact deflections are described using time-varying elastic foundations (Pasternak foundations) connected by independent contact stiffness. In order to account for thin-rimmed gears, a 3D finite element model of the gear (excluding teeth) is set up and a pseudo-modal reduction technique is used prior to solving the equations of motion. Depending on the gear structure, the results reveal a potentially significant influence of thin rims on both quasi-static and dynamic tooth loading.

2019 ◽  
Vol 281 ◽  
pp. 01006 ◽  
Author(s):  
Majid M.A. Kadhim ◽  
Mohammed J Altaee ◽  
Ali Hadi Adheem ◽  
Akram R. Jawdhari

Fibre reinforced cementitious matric (FRCM) is a recent application of fibre reinforced polymer (FRP) reinforcement, developed to overcome several limitations associated with the use of organic adhesive [e.g. epoxies] in FRPs. It consists of two dimensional FRP mesh saturated with a cement mortar, which is inorganic in nature and compatible with concrete and masonry substrates. In this study, a robust three-dimensional (3D) finite element (FE) model has been developed to study the behaviour of slender reinforced concrete columns confined by FRCM jackets, and loaded concentrically and eccentrically. The model accounts for material nonlinearities in column core and cement mortar, composite failure of FRP mesh, and global buckling. The model response was validated against several laboratory tests from literature, comparing the ultimate load, load-lateral deflection and failure mode. Maximum divergence between numerical and experimental results was 12%. Following the validation, the model will be used later in a comprehensive parametric analysis to gain a profound knowledge of the strengthening system, and examine the effects of several factors expected to influence the behaviour of confined member.


2014 ◽  
Vol 960-961 ◽  
pp. 1420-1423
Author(s):  
Zhi Dong Huang ◽  
Guo Fei Li ◽  
Juan Cong ◽  
Yun Wang ◽  
Wei Na Yu ◽  
...  

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Modal analysis of driving system and telescopic mechanism of bar on two wheels scooter is investigated. The first five orders natural frequency and major modes of driving system and telescopic mechanism of bar are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the two wheels scooter.


2011 ◽  
Vol 189-193 ◽  
pp. 2196-2199
Author(s):  
Ling Li Meng ◽  
Yan Qun Huang ◽  
Ming Liu

Since it is inconsistent and uncontrollable in the experiment, any variance in specimen dimensions, welding parameters and testing conditions will influence the consistency of testing results to some extent. In this paper, the Finite Element Method(FEM) is employed to solve this problem. A three-dimensional finite element model is established to simulate the deformation of I-steel during gas tungsten arc welding (TIG) with FEM software, which is set up to analysis the deformation of I-steel with different welding sequences.


2017 ◽  
Vol 7 ◽  
pp. 87-93
Author(s):  
Harshal Ashok Patil ◽  
Pawankumar Dnyandeo Tekale ◽  
Veerendra V. Kerudi ◽  
Jitendra S. Sharan ◽  
Ratnadip Arunrao Lohakpure ◽  
...  

ObjectiveThe study conducted to assess the effects of a fixed functional appliance (Forsus Fatigue Resistant Device; 3M Unitek, Monrovia, CA, USA) on the mandible with three-dimensional (3D) finite element stress analysis.Materials and MethodsA 3D finite element model of mandible with miniplate at mandibular symphysis was prepared using SolidEdge software along with the plate geometry. The changes were deliberated with the finite element method, in the form of highest von Mises stress and maximum principal stress regions.ResultsMore areas of stress were seen in the model of the mandible at cortical bone in canine region at bone and miniplate interface.ConclusionsThis fixed functional appliance studied by finite element model analysis caused more von Mises stress and principal stress in both the cortical bone and the condylar region.


2011 ◽  
Vol 90-93 ◽  
pp. 1212-1215 ◽  
Author(s):  
Yan Zeng ◽  
Zhi Yong Wang

In this paper dynamic behavior of the Ying Zhou main bridge in Luoyang is studied .The finite element analysis software ANSYS is adopted to set up three-dimensional finite element model of a CFT arch bridge of the main bridge .The natural periods and modes of the CFT arch bridge are calculated by using the subspace iteration method. Meanwhile its modal characteristics are analyzed. Some useful conclusions are got by the calculation and analysis of the bridge for the engineering construction.


2014 ◽  
Vol 597 ◽  
pp. 531-534
Author(s):  
Zhi Dong Huang ◽  
Yun Pu Du ◽  
Bao Quan Liu ◽  
Guang Yang ◽  
Yu Feng Liu ◽  
...  

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Finite element analysis of driving system on two wheels scooter is investigated. The stress and strain of driving system is investigated. The stress diagram and the strain diagram are obtained. The method and the result can be used as a reference of innovative design of two wheels scooter.


2014 ◽  
Author(s):  
Chengbi Zhao ◽  
Ming Ma

As the three-dimensional finite element model has become the de facto standard for ship structural design, interest in accurately transferring seakeeping loads to panel based structural models has increased dramatically in recent years. In today’s design practices, panel based hydrodynamic analyses are often used for mapping seakeeping loads to 3D FEM structural models. However, 3D panel based hydrodynamic analyses are computationally expensive. For monohull ships, methods based on strip theories have been successfully used in the industry for many years. They are computationally efficient, and provide good predictions for motions and hull girder loads. However, many strip theory methods provide only hull girder sectional forces and moments, such as vertical bending moment and vertical shear force, which are difficult to apply to 3D finite element structural models. Previously, the authors have proposed a hybrid strip theory method to transfer 2D strip theory based seakeeping loads to 3D finite element models. In the hybrid approach, the velocity potentials of strip sections are first calculated based on the ordinary 2D strip theories. The velocity potentials of a finite element panel are obtained from the interpolation of the velocity potentials of the strip sections. The panel pressures are then computed based on Bernoulli’s equation. Integration of the pressure over the finite element model wetted panels yields the hydrodynamic forces and moments. The equations of motion are then formulated based on the finite element model. The method not only produces excellent ship motion results, but also results in a perfectly balanced structural model. In this paper, the hybrid approach is extended to the 2.5D high speed strip theory. The simple Rankine source function is used to compute velocity potentials. The original linearized free surface condition, where the forward speed term is not ignored, is used to formulate boundary integral equations. A model based on the Series-64 hull form was used for validating the proposed hybrid method. The motion RAOs are in good agreement with VERES’s 2.5D strip theory and with experimental results. Finally, an example is provided for transferring seakeeping loads obtained by the 2.5D hybrid strip theory to a 3D finite element model.


1984 ◽  
Vol 106 (4) ◽  
pp. 243-248 ◽  
Author(s):  
D. A. Turcic ◽  
Ashok Midha

Until recently, vibration effects have generally been neglected in the design of high-speed machines and mechanisms. This has been primarily due to the complexity of the mathematical analysis of mechanisms with elastic links. With the advent of high-speed computers and structural dynamics techniques, such as finite element analysis, this is no longer regarded as such a formidable task. To date, with few exceptions, the analysis of elastic mechanism systems have been limited to a single type of mechanism (i.e., a four-bar or slider-crank) modeled with a small number of simple finite elements (usually beam elements). This paper develops the generalized equations of motion for elastic mechanism systems by utilizing finite element theory. The derivation and final form of the equations of motion provide the capability to model a general two- or three-dimensional complex elastic mechanism, to include the nonlinear rigid-body and elastic motion coupling terms in a general representation, and to allow any finite element type to be utilized in the model. A discussion of a solution method, applications, as well as an experimental investigation of an elastic four-bar mechanism will be presented in subsequent publications.


2020 ◽  
Vol 48 (6) ◽  
pp. 030006052092640
Author(s):  
Hongming Xu ◽  
Jiali Chen ◽  
Shilei Pu ◽  
Xiaoyan Li

This study was performed to investigate the feasibility of using a three-dimensional (3D) finite element model for laryngomalacia severity assessment. We analyzed laryngeal computed tomography images of seven children with laryngomalacia using Mimics software. The gray threshold of different tissues was distinguishable, and a 3D visualization model and finite element model were constructed. The laryngeal structure parameters were defined. The peak von Mises stress (PVMS) value was obtained through laryngeal mechanical analysis. The PVMS values of the laryngeal soft tissue and cartilage scaffolds were independently correlated with disease severity. After stress loading the model, the relationship between laryngomalacia severity and the PVMS value was apparent. However, the PVMS value of laryngeal soft tissue was not correlated with laryngomalacia severity. This study established the efficacy of a finite element model to illustrate the morphological features of the laryngeal cavity in infants with laryngomalacia. However, further study is required before widespread application of 3D finite element modeling of laryngomalacia. PVMS values of the laryngeal cartilage scaffold might be useful for assessment of laryngomalacia severity. These findings support the notion that structural abnormalities of the laryngeal cartilage may manifest as quantifiable changes in stress variants of the supraglottic larynx.


2017 ◽  
Vol 11 (05) ◽  
pp. 1750019 ◽  
Author(s):  
Tsuyoshi Ichimura ◽  
Kohei Fujita ◽  
Atsushi Yoshiyuki ◽  
Pher Errol Quinay ◽  
Muneo Hori ◽  
...  

Damage to buried pipelines due to complex ground responses has been reported at residential development sites and valley plains with complex ground structures. Three-dimensional (3D) ground amplification analyses using 3D, nonlinear, finite-element methods may be effective in predicting such damage; however, it is often difficult to construct ground structures that are capable of reproducing observational characteristics. In this paper, we propose a 3D ground structure optimization method using a 3000[Formula: see text] forward finite-element dynamic analysis with approximately 0.27 million degrees of freedom, enabled by combining an automated 3D finite-element model-generation method and a fast 3D finite-element wave propagation analysis method. This optimization method is capable of estimating 3D ground structure models that can reproduce observational data characteristics. The effectiveness of the method is shown through an illustrative example.


Sign in / Sign up

Export Citation Format

Share Document