Authors: P Chandra Rao, M Anil Kumar, M Nirmal Devi Kiran
Abstract: In mechanical transmission systems, gears play major role in transmitting the mechanical power. They operate under high torques or high rotations. these gears are designed with stand stress and forces exerted while operating. A Gear box provide torque multiplication which is widely used in various applications. The aim of this paper is to reduce weight of the conventional gear box without compromising the efficiency by using topology optimization techniques from ANSYS software. Gearbox is designed using PTC CREO parametric and exported to ANSYS. After performing the topology optimization again, the gear box is redesigned and final analysis is performed. Conventional structural steel is selected as material. Analysis is carried out on optimized gear and regular gear. Then by comparing the results the conclusion for optimized gear is selected.
Authors: Dasam Hari Satya Sai Srinivas, V Ravi Kumar, V Vijay Kumar
Abstract: In the paper, influence of hydrogen on mechanical properties of welded joints from heat-treatable structural steel plates were investigated. The heat treatment of welded plate specimens was performed, and then the specimens were charged with hydrogen electrolytically generated from 1 N H2SO4 solution. The following studies were carried out: static tensile test, hardness investigations, macroscopic metallographic investigations as well as investigations with the use of a scanning microscope. Hydrogen embrittlement of welded joints from steel plates was revealed by a distinct decrease of ductility and a slight decrease of strength. On the basis of metallographic investigations, it was found that in a fracture region there are fine pores created by the presence of hydrogen and its displacement due to formed stresses and plastic deformation. It was shown that welded joints are susceptible to hydrogen cracking in the heat affected zone and in the fusion zone.
Authors: S Giriprasad, Dr S Srinivasa Rao, Dr M K. Naidu
Abstract: Fibre Reinforced Polymer composite (FRPC) materials have wide applications in aircraft and automobile structures due to their high specific stiffness and strength properties. FRPC materials traditionally designed and manufactured as multiply laminates consists of several unidirectional layers resulting in a material with spatially uniform stiffness/strength properties. The fibre orientation angle in most of the applications typically held fixed and mostly limited to unidirectional. By limiting each layer to have a constant orientation angle over the entire structural component cannot fully make use of the directional material properties offered by composite layers. The laminated cylindrical shells are being used in submarine, underground mines, aerospace applications and other civil engineering applications. Buckling is also important factor to decide the failure of the structure. Pressure vessels, submarines and long columns will tend to buckle. To avoid the buckling failure, large amount of material will be used, it results the higher weight of the structure. Generally cylindrical shells such as pressure vessels are manufactured by steel alloys. In present days to reduce the weight of the structures, these are manufacturing by composite materials like carbon epoxy, Glass epoxy.
This study aims to increase the design load of laminated composite FRP cylinder under buckling load. Initially a hybrid laminate designed in Ansys workbench by considering six ply angles with all fibres oriented at zero degrees. Response surface optimization used to obtain different optimized fibre orientations in a laminate by considering output parameters as deformation and Inverse Reserve factor. The optimized fibre angles are applied to the Ring stiffened cylinder. The configuration that gives higher load multiplier will attain higher load carrying capacity. Ring stiffened cylinder modelled and Analysis performed in ansys workbench and materials considered are Epoxy carbon and Epoxy S-Glass. The results are compared with theoretical calculations.
Abstract: A flywheel used in machines serves as
a reservoir which stores energy during the period when
the supply of energy is more than the requirement and
releases it during the period when the requirement of
energy is more than supply. For example, in I.C. engines,
the energy is developed only in the power stroke which is
much more than engine load, and no energy is being
developed during the suction, compression and exhaust
strokes in case of four stroke engines. The excess energy
is developed during power stroke is absorbed by the
flywheel and releases its to the crank shaft during the
other strokes in which no energy is developed, thus
rotating the crankshaft at a uniform speed.
The flywheel is located on one end of the
crankshaft and serves two purposes. First, through its
inertia, it reduces vibration by smoothing out the power
stroke as each cylinder fires. Second, it is the mounting
surface used to bolt the engine up to its load The aim of
the project is to design a flywheel for a multi cylinder
petrol engine flywheel using the empirical formulas. A
parametric model of the flywheel is designed using 3D
modeling software Creo. The forces acting on the
flywheel are also calculated. The strength of the flywheel
is validated by applying the forces on the flywheel in
analysis software ANSYS. Structural analysis, modal
analysis and fatigue analysis are done on the flywheel.
Structural analysis is used to determine whether
flywheel withstands under working conditions. Fatigue
analysis is done for finding the life of the component.
Modal analysis is done to determine the number of mode
shapes for flywheel. Analysis is done for two materials
Gray Cast Iron and S Glass Epoxy to compare the
Abstract: This paper is Gear is one of the most
critical components in a mechanical power transmission
system, and most industrial rotating machinery. Spur
gear has teeth cut in parallel to each other and imposes
radial loads on shafts. Contact stresses are one of the
factors which effects performance of gears transmission.
This project work made an attempt to
summarize about contact stresses developed in a mating
spur gear which has involute teeth. A pair of spur gears
are taken from a lathe gear box and proceeded forward
to calculate contact stresses on their teeth. Contact
failure in gears is currently predicted by comparing the
calculated Hertz contact stress to experimentally
determined allowable values for the given material. The
method of calculating gear contact stress by Hertz’s
equation originally derived for contact between two
cylinders. Analytically these contact stresses are
calculated for different module, and these results are
compared with the results obtained in modeling analysis
in ANSYS. As there involves many iterations in
calculating contact stresses analytically a simplified
approach is made in VISUAL BASIC for different
parameters like module, power, speed. Etc.
A model of mating spur gears is generated in
PRO/ENGINEER and this model is imported to ANSYS
14.5 Package. The imported model is analyzed in
ANSYS workbench for calculating contact pressure for
different module of spur gear. These results are
compared with analytical results and thus conclusions
are made on observing the results. A result advises that
with increase in module, Contact Pressure decreases for
a pair of spur gears. Results help us to give better
performance and future scope in the power transmission
Abstract: — This project is process structural analysis and
balancing test for impeller before conducting over speed
test of manufacturing a component, it is essential to
check various properties of the component that may get
changed after the manufacturing process. The
Centrifugal Compressor Impellers are manufactured
from forgings, which is the basic raw material for
impellers. During the process of producing the impeller
from the forgings, the forgings have to undergo many
machining operations and welding processes. These
operations may change the mechanical properties and
these changes should be accounted in order to have good
performance and accuracy. Since the impeller is a high
speed rotating component, some stresses may get
induced in it and cause dimensional inaccuracies
depending upon the mechanical properties of the
Hence each Impeller of the Compressor rotor is
individually over speed in a vacuum chamber to a value
of 115% of Maximum continuous speed to check the
mechanical soundness of the impeller. After that
dimensional and Dye checks are carried out on oversped
impellers for any permanent deformations and
micro cracks at the welds. The whole process should be
done before the impeller is made ready to be mounted on
the rotor shaft. Before conducting the Over Speed Test
(O.S.T.) on the impeller, first it has to be balanced. The
reasons for balancing, procedure to be followed and the
detailed description of the over speeding test are
Various systems, methods and techniques are in use by patients and medical centers to provide the necessary information and to serve medical profession including hospital information systems. One of the most important services is Personal Health care Record (PHR) portability and management. This problem has become out of history of paper records kept separately by physicians, clinics, hospitals, pharmacies, insurance companies and patients themselves.
The detection of isomorphism among kinematic chains and their derived mechanism has been a hot area of research for last several years. In the present communication a resistance distance based computerized method is proposed and it is tested for planar kinematic chains up to ten links.................
Economizer is the best mechanical component which is used for trapping the heat of flue gasses. Economizers can be best applied in electricity generating power plants. Best way of utilisation of flue gas heat is by transferring it to the boiler feed water. Hence economizers are designed in such a way that feed water is allowed to pass the economizer through pipes..........................
The reasons behind the raise of the temperature of turbo jet engine of aircrafts was investigated which leads to damaging the engine and costs the government huge expenses in case the plane is on ground and costs lives and expenses in case the aircraft is in flight.......