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________________
Corresponing author: Ajay Kumar Choubey E-mail address: [email protected]
Doi: http://dx.doi.org/10.11127/ijammc2016.09.05 Copyright@GRIET Publications. All rights reserved.
Advanced Materials Manufacturing & Characterization Vol 6 Issue 2 (2016)
Advanced Materials Manufacturing & Characterization
journal home page: www.ijammc-griet.com
Analysis of Connecting Rod by the Finite Elements Method
Ajay Kumar Choubey1, RashmiDwivedi 2, GeetaAgnihotri3
1Research Fellow, TEQIP-II Project, MSME Department, Maulana Azad National Institute of Technology, Bhopal (M.P.) – 4620051 2Research Scholar, Mechanical Engg. Department, Maulana Azad National Institute of Technology, Bhopal (M.P.) – 4620051
3Professor, Mechanical Engg. Department, Maulana Azad National Institute of Technology, Bhopal (M.P.) – 4620051
Abstract In this paper, finite element analysis of single cylinder four stroke petrol
engines is taken as a case study. Connecting rod is high volume
production from automobile side; it is subjected to more Stress than
other engine components. The main aim of this paper is to determine the
von-Mises stresses, shear stresses, total deformation. In this paper, only
the static FEA of the connecting rod has been performed by the use of the
software. This work can be extended to study the effect of loads on the
connecting rod under dynamic conditions. A lot has been done and still a
lot has to be done in this field. Structural systems of connecting rod can
be easily analyzed using Finite Element techniques. So firstly a proper
Finite Element Model is developed using FEM software ANSYS 14.0. The
static loads acting on the connecting rods, after that the work is carried
out for safe design. In this study two different size connecting rod uses
for static analysis.
Keywords: Connecting rod, FEA, stress, static analysis etc
1. Introduction
Connecting rods are widely used in variety of car and bike
engines. It is an integral component of internal combustion
engine and classified under functional component. It acts as a
linkage between piston and crank shaft. The main function of
connecting rod is to transmit the translational motion of piston
to rotational motion of crank shaft. The function of the
connecting rod also involves transmitting the thrust of the piston
to the connecting rod. Connecting rod has three main zones.
The piston pin end, the center shank and the big end. The piston
pin end is the small end; the crank end is the big end. Connecting
rods are subjected to forces generated by mass and fuel
combustion(Tony George Thomas, 2011).
Kamaldeep Grover and BalvinderBudania (2012) carried out the
Finite Element Analysis and optimization of connecting rod
using ANSYS. The main objective of this study was to reduce the
weight for structural steel connecting rod.
Neeraj Kumar, P. M. Kasundra (2012)presented a method used
to verify the stress and deformation in the connecting rod using
the finite element method. The study only analyses the
connecting rod foot. The obtained results provided by this
method were compared to the results obtained by calculation.
Although, the Finite Element Method (FEM) is a very powerful
tool for simulation of the engineering problems, the FEM
simulation of non-linear problem is a time consuming
procedure. In the present paper, the connecting rod is simulated
with ANSYS 14.0 Software. Steel and Aluminum materials are
used for stress analysis.
2. Aim of the Study
The main objective of this work is to investigate the stresses on
different size of the connecting rod. In this paper, only the static
FEA of the connecting rod was performed. The aim of the paper
is to determine the von- Misses stresses, Shear stresses, Total
Deformation and Optimization of pressure in the existing
Connecting rod. If the existing design shows the failure, then
suggest the minimum pressure for the existing Connecting rods.
Also the comparison between two materialsof connecting rod
analyzed.
26
Fig.1. Connecting Rods
3. Methodology
The methodology adopted in this study consists of a number of
steps and sub steps. Starting from the creation of a 3-D FE model
and then defining input parameters such as material properties,
parameters. The mechanical boundary conditions were then
imposed on the model and the solution was done by meshing of
the model by using SOLID185 element type. The FE model was
made using ANSYS software. The steps of the study are shown in
the following chart:
Fig.2. Methodology 4. Finite Element Analysis
The 3-D FE model for connecting rod was created by using
ANSYS 14.0 software. The connecting rod is analyzed in ANSYS
in three steps. First is preprocessing which involves modeling,
geometric clean up, element property definition and meshing.
Next comes, solution which involves imposing boundary
conditions and applying loads on the model and then solution
runs. Next in sequence comes post processing, which involves
analyzing the results plotting different parameters like stress,
strain, total deformation and many. The mesh has been
generated using tetra free element and mesh size is 2. The Solid
185 element type is adopted to mesh the model. The mesh of the
connecting rod consists of 64944 elements, 12958 nodes are
included in the finite element model.
Figure 3 showing FE model of connecting rod model prepared in
ANSYS 12.0.1.
Fig.3. FE model of connecting rod
Figure 4 showing meshing of connecting rod FE model.
Fig.4. Meshing of connecting rod model
5. MATERIAL PROPERTIES OF CONNECTING ROD
Steel is used in this study withYoung’s Modulus (E) of 210000
MPa and Poisson’s ratio (υ) as 0.30 (Also taken tangent modulus
& strain hardening component). The density (ρ) of the Mild Steel
is taken as 7850 Kg/m3. The value of yield stress (σYS) is 250 MPa
and ultimate tensile stress (σUTS) is 410 MPa.
27
6. CALCULATION OF MAXIMUM FORCE Force acting on piston = area of piston Х gas pressure
This maximum gas force applied on the surface of piston from
where it will transfer to connecting rod through piston pin.
Table I: Specification of the engine to which connecting rod
belongs
Parameters Dimensions
Bore 57 mm
Engine Displacement 143.91 cc
Compression Ratio 9.5:1
Maximum Power 9.57 kW at 8500 rpm
Maximum Torque 11.68 m at 6500 rpm
7. Result& Discussion
Connecting rod simulation and modeling have done by ANSYS.
The simulation results as shown in below:
Fig.5. von-Mises stress at 0.5 MPa
Fig. 5 showing when the pressure on connecting rod small end is
0.5 MPa than the von-Mises stress value is 2.185 MPa.
Fig. 6 von-Mises stress at 2.5 MPa
Fig. 6 showing that when the pressure increasing from 0.5 to 2.5
MPa at small end than the value of von-Mises stress increasing
from 2.185 to 10.923 MPa
Fig.7. von-Mises stress at 3.5 MPa Fig. 7 showing when the pressure on connecting rod small end is
3.5 MPa than the von-Mises stress value is very high.
Max. Stress
28
Fig.8. Stress vs Pressure
Figure 8 disusing that all stresses value on connecting rod. It
show that when the pressure will increase from 0.5 to 4 MPa
than the value of stress also increasing.
Fig.9. von-Mises Stress vs Pressure
Figure 9 show that pressure will increase then von-Mises stress
also increases but steel is better from aluminum.
Small Connecting Rod –
Pressure(Mpa) Steel(Max) Aluminium(Max)
0.5 2.0 2.114
2.5 10.4 10.5
3.5 14.6 14.7
BigConnecting Rod –
Pressure(Mpa) Steel(Max) Aluminium(Max)
0.5 2.185 2.2
2.5 10.923 11.008
3.5 15.411 15.411
Conclusions
By the help of simulations some results are finding –
When the pressure on small end of connecting rod increases
from 0.5 to 3.5 MPa than the von-Mises stress also increases
from 2.185 to 15.2.
When the pressure applied on connecting rod than steel is
better perform comparison to aluminum.
References [1]. Tony George Thomas, S. Srikari, M. L. J Suman, “Design of
connecting rod for heavy duty applications produced by different processes for enhanced fatigue life”, SASTECH Journal, Vol. no. 10, Issue no. 1, Page no. 1-7, 2011.
[2]. A. Mirehei, M. HedayatiZadeh, A. Jafari, M. Omid , “Fatigue
analysis of connecting rod of universal tractor through finite element method (ANSYS)”, Journal of Agricultural Technology, Vol. no. 4, Issue no. 2, Page no. 21-27, 2008.
[3]. Anil kumar, Kamaldeep Grover, BalvinderBudania,
“Optimization of Connecting Rod Parameters using CAE Tools”, International Journal of Latest Trends in Engineering and Technology, Vol. no. 1, Issue no. 3, Page no. 98-104, 2012.
[4]. Mohammad Ranjbarkohan, Mohammad Reza Asadi,
MasoudMohammadi, AhangariHeidar, “Fatigue Analysis of Connecting Rod of Samand Engine by Finite Element Method”, Australian Journal of Basic and Applied Sciences, Vol. no. 5, Issue no. 11, Page no. 841-845, 2011.
[5]. Mansour Rasekh, Mohammad Reza Asadi, Ali Jafari, Kamran
Kheiralipour, “Obtaining Maximum Stresses in Different Parts of Tractor (Mf-285) Connecting Rods Using Finite Element Method”, Australian Journal of Basic and Applied Sciences, Vol. no. 3, Issue no. 2, Page no. 1438-1449, 2009.
[6]. Ram Bansal , “Dynamic Simulation of a Connecting Rod made of
Aluminum Alloy using Finite Element Analysis Approach”, IOSR Journal of Mechanical and Civil Engineering , Vol. no. 5, Issue no. 2,. Page no. 01-05, 2013.