A New Analysis Method of the Dry Sliding Wear Process Based on the Low Cycle Fatigue Theory and the Finite Element Method

2013 ◽  
Vol 23 (3) ◽  
pp. 1096-1106 ◽  
Author(s):  
Mohammad Abdi ◽  
Ali Karimi Taheri ◽  
Amirhamed Bakhtiarydavijani
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Sliding Wear ◽  
Low Cycle Fatigue ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Cycle Fatigue ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Wear Process

The Qualification of Safety Critical Structures by Finite Element Analytical Methods

1996 ◽  
Vol 210 (2) ◽  
pp. 203-207 ◽  
Author(s):  
A J Morris
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Error Control ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Method Error ◽  
Safety Critical ◽  
Critical Situation ◽  
Error Treatment

The paper introduces the concept of certifying or qualifying structures in a safety critical situation using the finite element method. Error control and error treatment methods for this purpose are discussed together with the associated role of testing. The underlying methodology follows the principles laid down in the SAFESA (SAFE Structural Analysis) method which is described in outline.

Multi-response optimization of tribological characteristics of aluminum MMCs using PCA

2014 ◽  
Vol 10 (2) ◽  
pp. 276-287
Author(s):  
Rajesh Siriyala ◽  
A. Gopala Krishna ◽  
P. Rama Murthy Raju ◽  
M. Duraiselvam
Keyword(s):  
Sliding Wear ◽  
Wear Behavior ◽  
Principal Component ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Sliding Velocity ◽  
Content Type ◽  
Wear Process ◽  
Response Optimization ◽  
Sliding Distance

Purpose – Since, wear is the one of the most commonly encountered industrial problems leading to frequent replacement of components there is a need to develop metal matrix composites (MMCs) for achieving better wear properties. The purpose of this paper is to fabricate aluminum MMCs to improve the dry sliding wear characteristics. An effective multi-response optimization approach called the principal component analysis (PCA) was used to identify the sets of optimal parameters in dry sliding wear process. Design/methodology/approach – The present work investigates the dry sliding wear behavior of graphite reinforced aluminum composites produced by the molten metal mixing method by means of a pin-on-disc type wear set up. Dry sliding wear tests were carried on graphite reinforced MMCs and its matrix alloy sliding against a steel counter face. Different contact stress, reinforcement percentage, sliding distance and sliding velocity were selected as the control variables and the response selected was wear volume loss (WVL) and coefficient of friction (COF) to evaluate the dry sliding performance. An L25 orthogonal array was employed for the experimental design. Optimization of dry sliding performance of the graphite reinforced MMCs was performed using PCA. Findings – Based on the PCA, the optimum level parameters for overall principal component (PC) of WVL and COF have been identified. Moreover, analysis of variance was performed to know the impact of individual factors on overall PC of WVL and COF. The results indicated that the reinforcement percentage was found to be most effective factor among the other control parameters on dry sliding wear followed by sliding distance, sliding velocity and contact stress. Finally the wear surface morphology of the composites has been investigated using scanning electron microscopy. Practical implications – Various manufacturing techniques are available for processing of MMCs. Each technique has its own advantages and disadvantages. In particular, some techniques are significantly expensive compared to others. Generally the manufacturer prefers the low cost technique. Therefore stir casting technique which was used in this paper for manufacturing of Aluminum MMCs is the best alternative for processing of MMCs in the present commercial sectors. Since the most important criteria of a dry sliding wear behavior is to provide lower WVL and COF, this study has intended to prove the application of PCA technique for solving multi objective optimization problem in wear applications like piston rings, piston rods, cylinder heads and brake rotors, etc. Originality/value – Application of multi-response optimization technique for evaluation of tribological characteristics for Aluminum MMCs made up of graphite particulates is a first-of-its-kind approach in literature. Hence PCA method can be successfully used for multi-response optimization of dry sliding wear process.

Development of Bifurcation Analysis Method for Rate Dependent Materials

2019 ◽  
Vol 794 ◽  
pp. 220-225
Author(s):  
Daiki Towata ◽  
Yuichi Tadano
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Bifurcation Analysis ◽  
Stiffness Matrix ◽  
Computational Method ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Tangent Stiffness Matrix ◽  
Rate Dependent ◽  
Element Method

In this study, a novel numerical method to analyze the bifurcation problemof a rate dependent material using the finite element method is proposed. The consistent stiffness matrix, which is required for a bifurcation analysis using the finite element method, for a rate dependent material is generally hard to compute, therefore, a computational method to calculate the tangent stiffness matrix based on a numerical differential is introduced so that exact bifurcation analyses for the rate dependent material can be conducted. A numerical example of the proposed method is demonstrated, and the adequacy of the proposed method is discussed.

Nonlinear Analysis Method Research of Multi-Bolt Connection Structure of Primary Equipment Support

2017 ◽  
Author(s):  
Jianrong Zou ◽  
Shaochong Zhou
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Steam Generator ◽  
Support System ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Reactor Coolant ◽  
Asme Code ◽  
Bolt Connection ◽  
Coolant System

The main equipments of the reactor coolant system include the steam generator, the reactor coolant pump, the pressurizer and the reactor coolant loop. The reactor coolant system is equipped with a steam generator for each of the two loops, and pressurizer is connected with the hot leg of loop 1 using the surge line. The main loop support system design of AP series greatly simplifies the RCS loop support system. Pressurizer supports consist of columns, lower lateral supports, upper lateral support and ring girder, and the steam generator supports consist of columns, lower lateral supports, upper lateral supports and intermediate lateral supports. Ring Girder of pressurizer consists of two semi-circular girders, vertical supports and splice connection of girder and the two half-ring girders are connected with splice connection using 11 bolts. The steam generator upper lateral support is mainly composed of bracket, snubber, pin and ubar and the ubar and the steam generator is connected via 16 bolts in the initial design. These bolts are to ensure the support junction can withstand the force and torque of various conditions of the reactor coolant system, which are important components of the main equipment support. There are large numbers of bolts in the splice connection of ring girder and ubar of upper lateral support of steam generator, and the bolts load was calculated using the uniform method in the general engineering design and analysis. During the design review it was found that the bolts load was uneven and in order to determine the non-uniformity of the bolts the finite element method was used to calculate the load on each bolt, and the resulting stress ratio was greater than 1 did not meet the requirements of the ASME Code. In this paper, the calculation method was studied and the design improvements for parts was made using the nonlinear analysis method to meet the requirements of ASME Code in the case of master supports of main equipment supports have been made good. At the same time the impact of bolts load because of gap was studied. It had very good economic benefits. The calculation and research of this paper show that the finite element method can calculate the force of bolts finely, and can get a more reasonable result than the empirical formula. It can be referred to when the multi-bolt connection structure needs to be refined, such as flange connection of important equipments and valves and flange and bolt design optimization.

scholarly journals INTEGRATED SLOPE STABILITY ANALYSIS (SSA) WITH TRANSIENT GROUNDWATER FINITE ELEMENT METHOD FOR EMBANKMENT ANALYSIS

2021 ◽  
Vol 83 (5) ◽  
pp. 9-17
Author(s):  
Supandi Sujatono
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Stability Analysis ◽  
Slope Stability ◽  
Slope Stability Analysis ◽  
Clay Material ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Element Method ◽  
Storage Facilities

The content of level has a big enough role in the value of the physical characteristic and the mechanical of material. The behavior of water in these materials needs to be analyzed first in order to support the slope stability analysis. Modeling of water behavior in materials in the construction of Tailing Storage Facilities (TSF) will be integrated in the slope stability analysis. This study aims to provide an explanation about the analysis of the Fishing Storage Facilities (TSF) which integrates transient groundwater analysis using the finite element method in supporting the stability analysis of the embankment of Tailing Storage Facilities (TSF). The variables that are used in the analysis, they are the parameters of physical properties and mechanic material for embankment and permeability parameters in analyzing groundwater. The analysis method for geotechnical and geohydrology modeling uses the finite element method. The results of analysis showed that groundwater behavior in the embankment material can be known in detail so that it can be integrated with stability analysis.   It can be seen that there is a decrease in the value of the slope safety factor using the Integrated Slope Stability Analysis method compared to the conventional method. Adding an impermeable layer using a thickness of 5 m of clay material and a thickness of 20-30 m to support the retaining wall/foot is the criterion of optimal stability. The required lining material thickness (D) can be expressed by the following drawdown percentage equation function:  reduction percentage = (1-0.8661D (-0.031)) * 100%.  

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