Finite Element Analysis of Dynamically Loaded Flexible Journal Bearings: A Fast Newton-Raphson Method

1989 ◽  
Vol 111 (4) ◽  
pp. 597-604 ◽  
Author(s):  
J. D. C. McIvor ◽  
D. N. Fenner
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Computing Time ◽  
Journal Bearings ◽  
Element Analysis ◽  
Dynamically Loaded ◽  
Newton Raphson ◽  
Time Required ◽  
Raphson Method ◽  
Isoparametric Elements

A fast Newton-Raphson method is presented for the finite element analysis of dynamically loaded flexible journal bearings. The method makes use of 8-node isoparametric elements for the lubrication analysis and 20-node isoparametric elements for the structural analysis. Results are presented for the Ruston and Hornsby 6VEB Mk III marine diesel big-end bearing using this method. The computing time required for this analysis is more than two orders of magnitude less than that previously reported for an elastohydrodynamic bearing analysis using a conventional Newton-Raphson method.

scholarly journals Efficient analysis of welding thermal conduction using the Newton–Raphson method, implicit method, and their combination

2020 ◽  
Vol 111 (7-8) ◽  
pp. 1929-1940 ◽  
Author(s):  
Zhongyuan Feng ◽  
Ninshu Ma ◽  
Wangnan Li ◽  
Kunio Narasaki ◽  
Fenggui Lu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Hybrid Method ◽  
Thermal Conduction ◽  
Computing Time ◽  
Implicit Method ◽  
Heating Process ◽  
Element Analysis ◽  
Heating And Cooling ◽  
Raphson Method

AbstractFinite element analysis is commonly used to investigate the thermal-mechanical phenomena during welding. To improve the computing efficiency of finite element analysis for welding thermal conduction, a novel Newton–Raphson method (NRM) without the computation of inverse matrix and a hybrid method combing the NRM and conventional implicit method (IMP) were developed. Comparison of computing time between the hybrid method implemented in an in-house software JWRIAN and the IMP used in a commercial software ABAQUS indicated that the computing speed of the former was about 4.5 times faster than that of the latter. Additionally, compared to the conventional IMP, the NRM exhibited higher computing efficiency in the analysis of transient thermal conduction during the welding heating process. Meanwhile, a combined hybrid method of the NRM and IMP was verified to be more efficient in analyzing the welding thermal conduction throughout the heating and cooling processes. Moreover, the thermal cycles computed by the hybrid method were consistent with those from experimental measurement, indicating the high accuracy of the hybrid method. Furthermore, the hybrid method was used to predict the temperature field of the corner boxing fillet joint welded by a low transformation temperature weld metal for generation of compressive residual stress.

A Finite Element Analysis of Dynamically Loaded Journal Bearings in Mixed Lubrication

1998 ◽  
Vol 41 (2) ◽  
pp. 273-281 ◽  
Author(s):  
Xiaolan Ai ◽  
Herbert S. Cheng ◽  
Dongyun Hua ◽  
K. Moteki ◽  
S. Aoyama
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Journal Bearings ◽  
Mixed Lubrication ◽  
Element Analysis ◽  
Dynamically Loaded

Application of an Improved Trust-Region Method to Rigid-Plastic Finite Element Analysis in Strip Rolling

2011 ◽  
Vol 704-705 ◽  
pp. 216-222
Author(s):  
Shu Ni Song ◽  
Jing Yi Liu ◽  
Jin Qian
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Computational Time ◽  
Damping Factor ◽  
Strip Rolling ◽  
Rigid Plastic ◽  
Element Analysis ◽  
Online Application ◽  
Newton Raphson ◽  
Raphson Method

Rigid-plastic finite element analysis (RPFEA) is an efficient and practical method to calculate rolling parameters in the strip rolling process. To solve the system of simulations equations involved in the RPFEA, a numerous of numerical methods, including the standard Newton-Raphson method, the modified Newton-Raphson method, and etc., have been proposed by different researchers. However, the computational time of the existed numerical methods can not meet the requirement of the online application. By tracking the computational time consumption for the main components in the standard Newton-Raphson method used in finite element analysis, it was found that linear search of damping factor occupies the most of the computational time. Thus, more efforts should be put on the linear search of damping factor to speed up the solving procedure, so that the online application of RPFEA is possible. In this paper, an improved trust-region method is developed to speed up the solving procedure, in which the Hessian matrix is forced to positive definite so as to improve the condition number of matrix. The numerical experiments are carried out to compare the proposed method with the standard Newton-Raphson method based on the practical data collected from a steel company in China. The numerical results demonstrate that the computational time of the proposed method outperforms that of the standard Newton-Raphson method and can meet the requirement of online application. Meanwhile the computational values of rolling force obtained by the proposed method are in good agreement with experimental values, which verifies the validity and stability of the proposed method.

A Non-Cyclic Method for Plastic Shakedown Analysis

2003 ◽  
Author(s):  
W. Reinhardt
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Computing Time ◽  
Strain Accumulation ◽  
Analysis Method ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Cyclic Phenomenon ◽  
Elastic Shakedown ◽  
Plastic Shakedown

Shakedown is a cyclic phenomenon, and for its analysis it seems natural to employ a cyclic analysis method. Two problems are associated when this direct approach is used in finite element analysis. Firstly, the analysis typically needs to be stabilized over several cycles, and the analysis of each individual cycle may need a considerable amount of computing time. Secondly, even in cases where a stable cycle is known to exist, the finite element analysis can show a small continuing amount of strain accumulation. For elastic shakedown, non-cyclic analysis methods that use Melan’s theorem have been proposed. The present paper extends non-cyclic lower bound methods to the analysis of plastic shakedown. The proposed method is demonstrated with several example problems.

Improved Rotative Mid-Point Mensuration and Newton-Raphson Method in 2-D Flat Rolling Simulation

2011 ◽  
Vol 328-330 ◽  
pp. 1436-1439
Author(s):  
Shu Ni Song ◽  
Jing Yi Liu
Keyword(s):  
Finite Element ◽  
Simultaneous Equations ◽  
Rigid Plastic ◽  
Cpu Time ◽  
Numerical Tests ◽  
Element Simulation ◽  
Flat Rolling ◽  
Newton Raphson ◽  
Time Required ◽  
Raphson Method

Newton-Raphson (N-R) method has been employed to solve the system of simultaneous equations arising in Rigid-Plastic finite element simulation. The combination of the improved rotative mid-point mensuration and the N-R method, named the M-P method is designated to solve the equations of velocity increment in Rigid-Plastic FEM. The CPU times required for calculation by the M-P method and the N-R method are compared and it is found that the CPU time required for calculation of the N-R method is more than the M-P method. The calculated rolling forces by the M-P method and the N-R method are compared and it is found that the former correlates better with the measured value. Numerical tests and application show that the M-P method is feasible and steady.

Finite Element Analysis in 3D Using the Penalty Boundary Method

2002 ◽  
Author(s):  
Brett W. Clark ◽  
David C. Anderson
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Mesh Generation ◽  
Discretization Error ◽  
Finite Element Models ◽  
Element Analysis ◽  
Hexahedral Elements ◽  
Boundary Method ◽  
Time Required

Traditional methods for applying boundary conditions in finite element analysis require the mesh to conform to the geometry boundaries. This in turn requires complex meshing algorithms for automated mesh generation from CAD geometry, particularly when using quadrilateral and hexahedral elements. The 3D extension of the penalty boundary method (PBM) is presented as a method that significantly reduces the time required generating finite element models because the mesh is not required to conform to the CAD geometry. The PBM employs penalty methods to apply boundary conditions on a simple, regular mesh. The PBM also eliminates discretization error because boundary conditions are applied using CAD geometry directly rather than an approximation of the geometry.

Development of A Three-Dimensional Membrane Element for the Finite Element Analysis of Tires

1991 ◽  
Vol 19 (1) ◽  
pp. 23-36 ◽  
Author(s):  
K. Ishihara
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Computing Time ◽  
Three Dimensional ◽  
Complex Nature ◽  
Element Formulation ◽  
Membrane Element ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Modeling Strategy

Abstract A three-dimensional membrane element was developed for the finite element analysis of tires. In general, the three-dimensional finite element analysis of tires uses a lot of computing time because of the complex nature of the problem. Major sources of complexity are, for example, nonlinearities in kinematics, material properties, boundary conditions, and the multilayer structure which is inherent to the tire. One of the ways to overcome this situation can be in the modeling strategy. This paper describes an approach where the cord-rubber composite components of the tire are modeled by membrane elements. The number of nodes required in the tire model using this strategy is considerably reduced, without any loss of accuracy, compared with models in which only ordinary solid elements are used. The nonlinear finite element formulation, numerical examples, and a comparison of the results with those obtained from models using solid elements and experimental values are given in the paper.

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