Quasi-Dynamic Stress Analysis on Crank Shaft of Computerized Variable Compression Ratio (VCR) Diesel Engine
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International Journal of Engineering Trends and Technology (IJETT) | 
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| © 2015 by IJETT Journal | ||
| Volume-30 Number-4 |
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| Year of Publication : 2015 | ||
| Authors : B.Nagaraju, J. Sampath Kumar, M.S.S.Srinivasarao, K.Naresh Kumar |
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| DOI : 10.14445/22315381/IJETT-V30P239 |
Citation
B.Nagaraju, J. Sampath Kumar, M.S.S.Srinivasarao, K.Naresh Kumar"Quasi-Dynamic Stress Analysis on Crank Shaft of Computerized Variable Compression Ratio (VCR) Diesel Engine", International Journal of Engineering Trends and Technology (IJETT), V30(4),204-211 December 2015. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group
Abstract
The main objective of this study was to
investigate the stresses induced in crankshaft
manufactured of AISI E4330 forged steel & an
aluminium alloy (7076-T6). A comparative analysis
was made to study the behaviour of materials. Crank
shaft is one of the most important moving part with a
complex geometry in internal combustion Engine. It
converts the reciprocating displacement of the piston
into a rotary motion. When combustion takes place in
the engine, there by high temperature and pressure
will be developed inside the engine cylinder. Due to
high speed and at high loads, the piston is subjected to
large structural stresses, which influences on the
crank.
Experimentation was carried out on a
Computerized Variable Compression Ratio (VCR)
Diesel Engine Test Rig at Compression ratio of 16.5
for obtaining he results. The obtained results were
tabulated for knowing pressure at various crank
angles. The results were analysed by drawing the
Pressure vs. crank angle variation diagram. The
dynamic analysis was carried out by developing the
equations of equilibrium from the Free Body
Diagrams of individual components of Slider-Crank
Mechanism. The forces induced at the pin joints and
inertia forces obtained from the dynamic analysis
were used as input for further analysis.
A three dimensional model of diesel engine
crankshaft is developed by using SOLID WORKS
software. And further analysis is carried out by using
ANSYS WORKBENCH 15.0 software. Dynamic
analysis parameter solving by MAT Lab. These
reaction forces are applied along with boundary
conditions on the FE model of crank shaft. The stress
analysis was performed at critical crank angles of
rotation.
Finite element analysis which consists (1) stress
analysis (2) Modal analysis and (3) fatigue analysis.
The structural analysis involves
determination of induced stresses and deformation for
all crank angles at crank pin and bearing supports.
The results in the form of von-Mises stresses and
deformation were determined for both materials.
Further the crank shaft is also subjected to
modal and fatigue analysis for maximum load
condition 3650, from the modal analysis observed
different mode shapes of crank shaft and also factor of
safety observed from the fatigue analysis.
The results obtained from the structural
analysis shows that the stresses induced at crank pin
and bearing supports in aluminium alloy (7076-T6)
are lesser in comparison with AISI E4330 forged steel
for various different crank angles.
The results obtained from modal analysis
were inferred that aluminium alloy (7076-T6) exhibits
lesser frequency in comparison with AISI E4330
forged steel for different mode shapes.
The fatigue analysis carried out to know the
factory of safety of the two materials for at 106 cycles.
The comparative results shows that the aluminium
alloy (7076-T6) exhibits better results in comparison
with AISI E4330 forged steel.
References
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Keywords
Dynamic analysis, SOLID WORKS,
ANASYS, Forged steel& Aluminium Alloy.