A Review on Dynamic Analysis of Machine Structure

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056
Volume: 04 Issue: 06 | June-2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1120
A REVIEW ON DYNAMIC ANALYSIS OF MACHINE STRUCTURE
Mahmood Gaznavi1, Anil Kumar G2, Satheesh.J 3, Madhusudhan T4
1 M.Tech student, Mechanical Department, Machine Design, SJBIT, Bengaluru, India
2 Associate Professor Mechanical Department, SJBIT, Bengaluru, India.
3 Professor Mechanical Department, SJBIT, Bengaluru, India
4Professor Mechanical Department, SJBIT, Bengaluru, India
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Abstract - Dynamic analysis of machine structure is
necessary to ensure not only the comfort of the users,
but ensure good conditions for the operation of
equipment supported. With increase in the rapid
development of changing technology there is a need for
proper optimization to increase the efficiency& job
accuracy. The objective of dynamic analysis is to
analyze the behavior of a structure, when subjected to
forcing function under resonance condition. This paper
outlines the dynamic analysis of machine structure
under different natural frequencies & mode shape by
using FEM packages. Vibration in a machine structure
due to unbalancing of masses is a major challenge
which can be analyzed & overcome.
Key Words: Dynamic analysis, vibration, modal
analysis, FEM packages, frequency & mode shape.
1. INTRODUCTION
Dynamics of structures studies movements of bodies
caused by forces applied to them and also the forces that
cause movements in structures. Structural Dynamics
testing and analysis contributes to progress in many
industries, including aerospace, auto making,
manufacturing, wood and paper Production, power
generation, defense, consumer electronics,
telecommunications and transportation. The adequate
dynamic analysis of structures implies the creation of
models that allow converting a pre-established entity, in a
complex way, into something that the current resources
can understand and model.
1.1 Vibration
The term vibration describes repetitive motion that can be
measured and observed in a structure. Unwanted
vibration can cause fatigue or degrade the performance of
the structure. Therefore it is desirable to eliminate or
reduce the effects of vibration. In other cases, vibration is
unavoidable or even desirable. In this case, the goal may
be to understand the effect on the structure, or to control
or modify the vibration, or to isolate it from the structure
and minimize structural response.
Free vibration is the natural response of a structure to
some impact or displacement. The response is completely
determined by the properties of the structure, and its
vibration can be understood by examining the structure's
mechanical properties. For example, when you pluck a
string of a guitar, it vibrates at the tuned frequency and
generates the desired sound. The frequency of the tone is a
function of the tension in the string and is not related to
the plucking technique.
Forced vibration is the response of a structure to a
repetitive forcing function that causes the structure to
vibrate at the frequency of the excitation. For example, the
rear view mirror on a car will always vibrate at the
frequency associated with the engine's RPMs. In forced
vibration, there is a relationship between the amplitude of
the forcing function and the corresponding vibration level.
The relationship is dictated by the properties of the
structure.
1.2 Dynamic Analysis
Dynamic analysis can be used to determine the vibration
characteristics (natural frequencies and mode shapes) of a
structure or a machine component while it is being
designed. It also can be starting point for another, more
detailed, dynamic analysis, such as a transient analysis, a
harmonic analysis, or a spectrum analysis. Dynamic
analysis is the study of the dynamic properties of
structures under vibrational excitation.
2. LITERATURE REVIEW
Rafael Marin Ferro [1] conducted a performance check of
support frame structure to estimate the dynamic loads
caused by rotating equipment on supports using
computational models with strap software. The paper
concluded that fully rigid structures is suitable for
dynamic structure point of view

Jayarajan P. [2] studies revealed the dynamic analysis of
turbo-generator machine foundations. This paper outlines
the procedure for finite element modeling of foundation
structure by considering both free vibration analysis &
harmonic forced analysis. This paper concluded various
challenges relater to modeling of structure, machine & soil
for dynamic analysis.
Zissimos.P Mourelatos [3] demonstrated structural
dynamic analysis of crankshaft system model of internal
combustion engines. In this paper author uses two-level
dynamic sub structuring technique to analyze the dynamic
response based on FEM model. Reynolds’s equation&
load- dependent Ritz vector method has been used for two
level technique. The paper concluded the behavior of
machine structure with respect to various frequency
graph. Inertia reduction with the effect of elastomers
damping.
P.S Shenoy [4] explained detailed load analysis under
service loading conditions for a typical connecting rod,
followed by quasi-dynamic finite element analysis (FEA)
to capture stress variations over a cycle of operation. In
this paper, comparison of stresses using static FEA & quasi
dynamic FEA. Static analysis of a connecting rod which can
yield unrealistic stresses, whereas quasi-dynamic analysis
provides more accurate better suited for fatigue design
and optimization analysis of this high volume production
component. The mean load changes with length of
connecting rod as well as with change in engine speed.
H.Hirani [5] demonstrated damping coefficients of an
engine bearing over a load cycle. Dynamic engine loads
technique is used to determine the shaft cycle limit. This
paper theoretical model is used, which is based on short &
long bearings. This paper outline the results based on
stiffness & damping coefficient validation which gives
realistic results compared to thermal analysis.
Pravin A Renuke [6]
The paper highlighted the vibrational characteristics of the
optimization of car chassis including the natural
frequencies and mode shapes. The author considered
modal analysis using FEM to carry out the demonstration.
He concluded that decreases the chassis length, can
increase the chassis stiffness which can prevent resonance
phenomenon and unusual chassis vibration and place the
natural frequencies in natural range.
B.V Subrahmanyam [7] outlined the static & dynamic
analysis of machine tool structure to prevent the gradual
failure of machine. The author uses FEA modelling &
modal analysis method to demonstrate the challenges.
Lathe machine, shaper machine, milling machine has been
used in this paper. It is shown that Von Misses stress
observed is high for lathe. In all machines, the stresses are
high along x-direction, is a direction transverse to the
longitudinal axis. The deflection is observed to be more
predominant in milling machine.
Namdev .A. Patel [8] studied the vibrational analysis of CI
engine with the help of FFT analyzer. The paper is framed
as engine rigid body modeling, engine vibrations in detail
and at last some experimental work performed on a single
cylinder diesel engine to measure vibrations using FFT
spectrum analyzer. The author concluded that magnitude
of Vibration depends upon selection of axis of engine for
acquisition of signatures. From analysis we get to know
vibrations are greater in Y direction as compared with X
and Z direction. Magnitude of vibration depends upon
engine speed. As the speed of engine decreases the
vibration acceleration amplitude also decreases in Y
direction but increases in X and Z direction. With increase
in load on engine the fuel rate increases, vibrations in Y
direction decreases but increases in X and Z direction.
S.C Jaisawal [9] studied multi body dynamic analysis &
simulation of engine model. This paper has an overview of
the model with a new running speed which generate the
challenges of stress in the connecting rod. It is concluded
that there is no stress developed in any component of the
engine at a particular given speed of 4mm/s. So the model
is successful for that speed or less. Beyond this the
stresses will develop and the model will fail.
Sondipon Adhikari [10] demonstrated dynamic analysis
of framed structure with statistical uncertainties. The
analysis is based on the assembly of element stochastic
dynamic stiffness matrices. The solution involves
inversion of the global dynamic stiffness matrix, which, in
this case, turns out to be a complex-valued symmetric
random matrix.
Jovan Validic [11] studied on dynamic behavior of the
loading lifting mechanisms. In this paper, the step of
establishing the correct dynamic model and
corresponding equations is proposed. It’s on the analysis
of the relevant influences, such as variation of the rope
free length, slipping of the elastic rope over the drum or
pulley and damping due to the rope internal friction. The
concluded talk on this dynamic model for elevator driving
mechanism provides the analysis of relevant parameters
and a base for the assessment of lifting process stability
through the critical velocity level.
Piyush K. Bhandari [12] described dynamic analysis of
machine foundation. The two parameters named as
limiting amplitude and operating frequency of a machine
to be considered in analysis of machine foundation. The
author has taken Elastic half space analogy method with
embedment coefficients into considerations which can be
used for coupled modes of vibration to get the natural
frequencies and forcing function. The paper concluded the
cause of amplitudes uncoupled vibrations in sliding as well

as in rocking modes are less as compared to coupled
vibrations. At higher depth of embedment the total
vertical and horizontal vibration response decreases. The
natural frequency of foundation increases with increase in
depth of embedment of foundation.
Darina Hroncova [13] outlined the dynamic analysis of
shaping machine mechanisms. Mathematical model has
been used for mechanisms and was completed using MSC
Adams. Program MSC Adams/View makes it easy to
analyze complex mechanical systems with multiple
degrees of freedom.
T. Raja Santosh Kumar [14] outlined the design and
dynamic analysis of flywheel. Modeling software pro/e has
been used & analyzed at different time interval with
different loading conditions for power 20kw and speed at
400 rpm to 410 rpm. The author aimed is to reduction of
weight. The wheel-shaped structure contributes to
decrease stress concentration. The wheel-shaped
structure is advantageous to get good performance and
reduce the cost.
Giacomo Bianchi [15] highlighted the use of damping in
machine tools to suppress the vibration during dynamic
analysis. Transferring energy dissipation mechanisms into
numerical structural models. It is concluded that at
multiple point which allows to investigate the complex
interaction, in a machine tool, between structural
dynamics, motion control and friction forces.
Anayet U.Patwari [16] presented a study on dynamic
modal analysis of vertical machining center components.
The main objective was to deal with the results of different
mode shape of components. Modeling has been done by
Catia & analysis performed in abacus. Closeness of results
was observed between natural frequencies of finite
element modeling and model testing. The concluded
results shown that the suitable frequency ranges for end
milling will be up to 12000 Hz.
3. CONCLUSIONS
 Dynamic analysis shows the closeness of
results between frequency & forcing function.
 Dynamic analysis provides a goods
efficiency& reduce the costs through
optimization of the structures.
 Material design should be below the critical
stress of the materials.
 FFT analysis is a better technique to get the
signature of frequency response of dynamic
analysis.
 Unwanted vibration can be suppressed with
the use of damping system & balancing of
masses.
 Quasi static dynamic analysis provides more
accurate better suited for fatigue design and
optimization analysis of this high volume
production component.
 The better design of the material can reduce
the stress concentration.
4. REFERENCES
[1] Rafael Marin Ferro, Walnó Graça rio Ferreira &
Adenilcia Fernanda Grobério Calenzani Dynamic Analysis
of Support Frame Structures of Rotating Machinery Global
Journal of Researches in Engineering: e Civil and
Structural Engineering Volume 14 Issue 5 Version 1.0 Year
2014
[2] Jayarajan P.,Kouzer K.M. dynamic Analysis of Turbo-
generator Machine Foundations, Journal of Civil
Engineering and Environmental Technology Volume 1,
Number 4; August, 2014.
[3] Zissimos .P. Movrelatos, A crankshaft system model for
structural dynamic analysis of internal combustion
engines 14 June 2002.
[4] P S Shenoy and A Fatemi Dynamic analysis of loads
and stresses in connecting rods Department of Mechanical,
Industrial, and Manufacturing Engineering, The University
of Toledo, Toledo, Ohio, USA, 6 Feb 2016
[5] H. Hirani, K. Athre and S. Biswa Sb dynamics analysis of
engineering bearings International Journal of Rotating
Machinery1999, Vol. 5, No. 4, pp. 283-293
[6] Pravin A Renuke Dynamic Analysis of a Car Chassis
IJERA Vol. 2, Issue 6, November- December 2012, pp.955-
959
[7] B.V. Subrahmanyam, A. Srinivasa Rao, S.V. Gopala
Krishna, CH. Rama Krishna Static and Dynamic Analysis of
Machine Tool Structures IJRMET Vol. 4, Issue Spl - 1, Nov
2013- April 2014
[8] Namdev a. Patil, laukik p. Raut vibration analysis of ci
engine using FFTanalyzer IJERT
[9] Dr. S.C. Jaiswal , Rahul Singh multi body dynamic
analysis and simulation of engine model IJRET Vol. 3 No.
10 October 2011
[10] Sondipon adhikariand c. S. Manohar dynamic analysis
of framed structures with statistical uncertainties, int. J.
Numer. Meth. Engng. 44, 1157{1178 (1999)
[11] Jovan vladic, petar malesev, rastislav sostakov -
nikola brkljac dynamic analysis of the load lifting
mechanisms journal of mechanical engineering
54(2008)10, 655-661

[12] Piyush k. Bhandari, ayan sengupta dynamic analysis
of machine foundation ijret an iso 3297: 2007 certified
organization volume 3, special issue 4, April 2014.
[13] Darina Hroncov, Ingrid Delyova, Peter Frankovsky,
Anna Puzderova Dynamic Analysis of the Shaping Machine
Mechanism American Journal of Mechanical Engineering,
2013, Vol. 1, No. 7, 370-373
[14] T. Raja Santosh Kumar, Suresh Babu Koppula, Cr.
Prakash, D.V.Srikanth Design and Dynamic Analysis of
Flywheel IOSR Journal of Mechanical and Civil Engineering
(IOSR-JMCE) e-ISSN: 2278-1684, p-ISSN : 2320–334X PP
51-56.
[15] Giacomo bianchi, stefano cagna, nicola cau, Francesco
paolucci analysis of vibration damping in machine tools
Science direct procedia cirp 21 ( 2014 ) 367 – 372.
[16] Anayet u. Patwari, waleed f. Faris, a. K. M. Nurul amin,
and S. K. Loh dynamic modal analysis of vertical machining
Centre components hindawi Publishing Corporation
Advances in acoustics and vibration Volume 2009, article
id 508076, 10 pages.

A Review on Dynamic Analysis of Machine Structure

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