This presentation gives an information about: photoelasticity, covering syllabus of Unit-3, of Experimental stress analysis subject for BE course under Visvesvaraya Technological University (VTU), Belgaum.
Experimental stress analysis BE notes by mohammed imranMohammed Imran
7th semester, Experimental stress analysis notes as per VTU syllabus by Mohammed Imran, Asst. Prof., Department of Mechanical Engineering, Ghousia College of Engineering-Ramanagaram-562159
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
Experimental stress analysis BE notes by mohammed imranMohammed Imran
7th semester, Experimental stress analysis notes as per VTU syllabus by Mohammed Imran, Asst. Prof., Department of Mechanical Engineering, Ghousia College of Engineering-Ramanagaram-562159
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
Introduction to Digital Image Correlation (DIC)Instron
This presentation introduces Digital Image Correlation, the optical technique that compares images of a tested specimen’s surface to generate full-field strain and displacement maps.
Material Characterization Testing, Unit IV; OML751 Testing of Materials Dr.S.Thirumalvalavan
Material Characterization Testing, Unit-IV
Subject Name: OML751 Testing of Materials
Topics: Material Characterization Testing [Optical microscopy, Electron microscopy-SEM, TEM. Diffraction techniques, Spectroscopy techniques. Electrical and Magnetic techniques.
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Mumbai University.
Mechanical Engineering
SEM III
Material Technology
Module 2.2
Fatigue Failure:
Definition of fatigue and significance of cyclic stress, Mechanism of fatigue and theories of fatigue failure, Fatigue testing, Test data presentation and statistical evolution, S-N Curve and its interpretation, Influence of important factors on fatigue, Notch effect, surface effect, Effect of pre-stressing, corrosion fatigue, Thermal fatigue.
NON DESTRUCTIVE TESTING TECHNIQUES ARE USEFUL FOR FINDING DEFECTS LIKE CRACKS,POROSITY,FLAWS,BLOWHOLES IN MATERIALS WITHOUT DESTRUCTING COMPONENT. IT IS ALSO USEFUL FOR TAKING DECISIONS RELATED TO QUALITY OF MATERIAL OR PRODUCT. Non destructive testing includes study and testing of components by various methods such as dye penetration test, eddy current test, magnetic particle test, ndt, radiography test, ultrasonic test.
Introduction to Digital Image Correlation (DIC)Instron
This presentation introduces Digital Image Correlation, the optical technique that compares images of a tested specimen’s surface to generate full-field strain and displacement maps.
Material Characterization Testing, Unit IV; OML751 Testing of Materials Dr.S.Thirumalvalavan
Material Characterization Testing, Unit-IV
Subject Name: OML751 Testing of Materials
Topics: Material Characterization Testing [Optical microscopy, Electron microscopy-SEM, TEM. Diffraction techniques, Spectroscopy techniques. Electrical and Magnetic techniques.
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Mumbai University.
Mechanical Engineering
SEM III
Material Technology
Module 2.2
Fatigue Failure:
Definition of fatigue and significance of cyclic stress, Mechanism of fatigue and theories of fatigue failure, Fatigue testing, Test data presentation and statistical evolution, S-N Curve and its interpretation, Influence of important factors on fatigue, Notch effect, surface effect, Effect of pre-stressing, corrosion fatigue, Thermal fatigue.
NON DESTRUCTIVE TESTING TECHNIQUES ARE USEFUL FOR FINDING DEFECTS LIKE CRACKS,POROSITY,FLAWS,BLOWHOLES IN MATERIALS WITHOUT DESTRUCTING COMPONENT. IT IS ALSO USEFUL FOR TAKING DECISIONS RELATED TO QUALITY OF MATERIAL OR PRODUCT. Non destructive testing includes study and testing of components by various methods such as dye penetration test, eddy current test, magnetic particle test, ndt, radiography test, ultrasonic test.
Stress Analysis of Different Geometries of Crane Hook Using Diffused Light Po...paperpublications3
Abstract: In this project, we use diffused light polariscope for studying various complex geometries of crane hook. For this entire study, we select four different types of hooks which are used in crane for lifting purpose. Crane Hooks are highly liable components and are always subjected to failure due to accumulation of large amount of stresses which can eventually lead to its failure. To study the stress pattern, the different acrylic models of crane hook are loaded in diffused light polariscope. The stress distribution pattern is verified for its correctness on ANSYS software. By predicting the stress concentration area, the shape of the crane is modified to increase its working life and reduce the failure rates. By observing the stress pattern in acrylic models, we calculate the stress concentration factor for different geometries. After comparing the acrylic models on the basis of stress concentration factor, we find that which one is best geometry out these four selected geometries for various lifting load conditions.
MAHARASHTRA STATE BOARD
CLASS XI AND XII
PHYSICS
CHAPTER 7
WAVE OPTICS
CONTENT:
Huygen's principle.
Huygen's principles & proof of laws of reflection/refraction.
Condition for construction & destruction of coherent waves.
Young's double slit experiment.
Modified Young's double slit experiment.
Intensity of light in Y.D.S.E.
Diffraction due to single slit.
Polarisation & doppler effect.
Thermal Radiation-I - Basic properties and Lawstmuliya
This file contains slides on RADIATION-I: Basic Properties and Laws.
The slides were prepared while teaching Heat Transfer course to the M.Tech. students in Mechanical Engineering Dept. of St. Joseph Engineering College, Vamanjoor, Mangalore, India, during Sept. – Dec. 2010.
Contents: Introduction – Applications – Electromagnetic spectrum – Properties and definitions – Laws of black body radiation – Planck’s Law – Wein’s displacement law – Stefan Boltzmann Law – Radiation from a wave band – Emissivity – Kirchoff’s Law- Problems
Model the vector nature of light (Linear, Circular, Mueller/Stokes/Jones Matrix, Poincaré sphere ) and optical components that manipulate polarization (e.g., polarizing filters and quarter-wave plates).
This paper shows my findings for determining the grating constant of a diffraction grating, the wavelengths of each line of the spectrum of hydrogen, and experimentally calculating the Rydberg constant.
First experimental realization of a Thermal ratchet using lasers. A thermal ratchet was a device proposed by Feynman that has the apparent ability to extract direct motion from random noise. Translated into Finance, this concept gave birth to the Parrondo paradox, a trading strategy that has the apparent ability to extract profits (positive PL) from random movements in the price of the underlier.
This presentation gives the information about introduction to control systems
Subject: Control Engineering as per VTU Syllabus of Aeronautical Engineering.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
Disclaimer:
The contents used in this presentation are taken from the text books mentioned in the references. I do not hold any copyrights for the contents. It has been prepared to use in the class lectures, not for commercial purpose.
This template was created for DSCE, Aeronautical students. You have to replace the institution details.
Create a separate document for each chapter, so that under numbering, you can change the sequence of chapter main heading according to chapter wise. i.e., 2.1, 2.2 etc.
Same procedure is applicable to Figure caption and Table caption.
This template can be used to generate, BE seminar report, M.Tech and Ph.D thesis also.
This template is created to assist UG students in generating their thesis without much hassle.
Contents are taken from VTU website. I don’t hold any copyright for this document.
Hareesha N G
Assistant Professor
DSCE, Bengaluru
This document is an Instruction manual for Computer aided machine drawing
Subject: Computer aided machine drawing (CAMD)
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit-8: Torsion of circular shafts and elastic stability of columns. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit-8: Torsion of circular shafts and elastic stability of columns. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 6: Bending and shear Stresses in beams. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 5 shear force and bending moment in beams. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 3 Compound stresses. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 2 stresses in composite sections. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document contains: Mechanics of Materials: Question bank from old VTU Question papers ; Pprepared by Hareesha N G, DSCE, Bengaluru. These questions are picked from last 06 years of old VTU question papers.
This presentation was prepared for a seminar. I have shared this with you. This is not related to curriculam. Please writre your criticisms to: hareeshang@gmail.com.
This presentation gives the information about Screw thread measurements and Gear measurement of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-4.
This presentation gives the information about Force, Pressure and Torque measurements of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-6.
This presentation gives the information about mechanical measurements and measurement systems of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-5.
This CIM and automation laboratory manual covers the G-Codes and M-codes for CNC Turning and Milling operations. Some concepts of Robot programming are also introduced.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
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ML for identifying fraud using open blockchain data.pptx
Photoelasticity
1.
2. UNIT-3: Photo-elasticity:
• Nature of light, Wave theory of light
• optical interference , Stress optic law,
• effect of stressed model in plane and circular polariscopes,
• Isoclinics & Isochromatics,
• Fringe order determination
• Fringe multiplication techniques,
• Calibration photoelastic model materials
08 Hours
4/4/2014 2Hareesha N G, Asst Prof,DSCE, Blore
3. Nature of Light
• Huygens (1629—1695) attempted to explain the optical effects
associated with thin films, lenses and prisms with a wave theory.
• In this theory, light is considered as a transverse disturbance in a
hypothetical medium, of zero mass, called the ether.
• At the same time Newton (1642—1727) proposed his corpuscular
theory, in which light is visualized as a stream of small but swift
particles (corpuscles) emanating from shining bodies in all directions,
travelling at the speed of light.
• The next major step in the evolution of the theory of light was due to
Maxwell (1831—1879), who presented the electromagnetic wave
theory.
• Here light is an electromagnetic disturbance, propagating through
space, represented by two vectors (electric and magnetic) mutually
perpendicular and perpendicular to the direction of wave
propagation.
• The most recent theory is the wave-mechanic or quantum theory,
which is a combination of the first two theories.
• The photo-elastic effect can be conveniently explained by adopting
either the wave theory or the electromagnetic theory.
4/4/2014 3Hareesha N G, Asst Prof,DSCE, Blore
4. WAVE THEORY OF LIGHT
• Electromagnetic radiation is predicted by Maxwell's theory to be a
transverse wave motion which propagates with an extremely high velocity.
• Associated with the wave are oscillating electric and magnetic fields which
can be described with electric and magnetic vectors E and H.
• These vectors are in phase, perpendicular to each other, and at right angles
to the direction of propagation.
• A simple representation of the electric and magnetic vectors associated
with an electromagnetic wave at a given instant of time is illustrated in Fig.
4/4/2014 4Hareesha N G, Asst Prof,DSCE, Blore
6. • All types of electromagnetic radiation propagate with the same velocity in free
space, approximately 3 x 108 m/s.
• The parameters used to differentiate between the various radiations are
wavelength and frequency.
• The two quantities are related to the velocity by the relationship
λf=c
where λ = wavelength
f= frequency
c = velocity of propagation
• The electromagnetic spectrum has no upper or lower limits.
• The radiations commonly observed have been classified in the broad general
categories shown in Fig.
4/4/2014 6Hareesha N G, Asst Prof,DSCE, Blore
8. • Light is usually defined as radiation that can affect the human eye.
• From Fig. it is evident that the visible range of the spectrum is a small
band centered about a wavelength of approximately 550 nm.
• The limits of the visible spectrum are not well defined because the
eye ceases to be sensitive at both long and short wavelengths;
however, normal vision is usually in the range from 400 to 700 nm.
• Within this range the eye interprets the wavelengths as the different
colors.
• Light from a source that emits a continuous spectrum with near equal
energy for every wavelength is interpreted as white light.
• Light of a single wavelength is known as monochromatic light.
4/4/2014 8Hareesha N G, Asst Prof,DSCE, Blore
9. Effects of a stressed model in a plane polariscope
• Consider a plane-stressed model inserted into the field of a plane
polariscope with its normal coincident with the axis of the
polariscope, as illustrated in Fig.
• Note that the principal-stress direction at the point under
consideration in the model makes an angle α with the axis of
polarization of the polarizer.
4/4/2014 9Hareesha N G, Asst Prof,DSCE, Blore
10. Effects of a stressed model in a plane polariscope
• We know that a plane polarizer resolves an incident light
wave into components which vibrate parallel and
perpendicular to the axis of the polarizer.
• The component parallel to the axis is transmitted, and the
component perpendicular to the axis is internally absorbed.
• Since the initial phase of the wave is not important , the
plane-polarized light beam emerging from the polarizer can
be represented by the simple expression
4/4/2014 10Hareesha N G, Asst Prof,DSCE, Blore
11. Effects of a stressed model in a plane polariscope
• After leaving the polarizer, this plane-polarized light wave enters the
model, as shown in Fig.
• Since the stressed model exhibits the optical properties of a wave
plate (Doubly refracting material), the incident light vector is resolved
into two components E1 and E2 with vibrations parallel to the
principal stress directions at the point.
4/4/2014 11Hareesha N G, Asst Prof,DSCE, Blore
12. Effects of a stressed model in a plane polariscope
• Thus
• Since the two components propagate through the model with
different velocities ( c > v1 > v2), they develop phase shifts Δ1 and Δ2
with respect to a wave in air.
• The waves upon emerging from the model can be expressed as
where
4/4/2014 12Hareesha N G, Asst Prof,DSCE, Blore
13. • After leaving the model, the two components continue to
propagate without further change and enter the analyzer in
the manner shown in Fig.
• Since the vertical components are internally absorbed in
the analyzer, they have not been shown in Fig.
4/4/2014 13Hareesha N G, Asst Prof,DSCE, Blore
The light components E1’ and
E'2 are resolved when they
enter the analyzer into
horizontal components E1’’
and E"2 and into vertical
components.
14. • The horizontal components transmitted by the analyzer combine to
produce an emerging light vector Eax, which is given by
Using in the above equation,
we get,
• It is interesting to note in the above Eqn that, the average angular
phase shift (Δ2+Δ1)/2 affects the phase of the light wave emerging
from the analyzer but not the amplitude.
4/4/2014 14Hareesha N G, Asst Prof,DSCE, Blore
15. • Since the intensity of light is proportional to the square of the
amplitude of the light wave, the intensity of the light emerging from
the analyzer of a plane polariscope is given by
4/4/2014 15Hareesha N G, Asst Prof,DSCE, Blore
16. Effects of a stressed model in a circular polariscope (Dark
Field, Arrangement A)
• When a stressed photo-elastic model is placed in the field of a
circular polariscope with its normal coincident with the z axis, the
optical effects differ significantly from those obtained in a plane
polariscope.
4/4/2014 16Hareesha N G, Asst Prof,DSCE, Blore
To illustrate this effect, consider the
stressed model in the circular
polariscope (arrangement A) shown in
Fig.
19. Effect of Principal-Stress Directions
• When 2α = nπ, where n = 0, 1, 2,..., sin2 2α = 0 and extinction
occurs.
• This relation indicates that, when one of the principal-stress
directions coincides with the axis of the polarizer (α = 0, π /2, or
any exact multiple of π /2) the intensity of the light is zero.
• Since the analysis of the optical effects produced by a stressed
model in a plane polariscope was conducted for an arbitrary point
in the model, the analysis is valid for all points of the model.
• When the entire model is viewed in the polariscope, a fringe
pattern is observed; the fringes are loci of points where the
principal-stress directions (either or a2) coincide with the axis of
the polarizer.
• The fringe pattern produced by the sin2 2α term in Eq. is the
isoclinic fringe pattern.
• Isoclinic fringe patterns are used to determine the principal-stress
directions at all points of a photo-elastic model.
4/4/2014 19Hareesha N G, Asst Prof,DSCE, Blore
20. Effect of Principal-Stress Difference
• When Δ/2 = nπ, where n = 0, 1, 2, 3,..., sin2 (Δ /2) = 0 and
extinction occurs.
• When the principal-stress difference is either zero (n = 0) or
sufficient to produce an integral number of wavelengths of
retardation (n = 1, 2, 3,...), the intensity of light emerging
from the analyzer is zero.
• When a model is viewed in the polariscope, this condition
for extinction yields a second fringe pattern where the
fringes are loci of points exhibiting the same order of
extinction (n = 0,1, 2, 3,...).
• The fringe pattern produced by the sin2 (Δ /2) term in Eq. is
the isochromatic fringe pattern.
4/4/2014 20Hareesha N G, Asst Prof,DSCE, Blore
21. Isoclinics
• The human eye is very sensitive to minima in light intensity.
• From Eqn
it is seen that either one of two conditions will prevent light that
passes through a given point in the specimen from reaching the
observer, when a plane polariscope is used. The first condition is that
4/4/2014 21Hareesha N G, Asst Prof,DSCE, Blore
22. • Since α is the angle that the maximum principal normal
stress makes with the polarizing direction of the
analyzer, this result indicates that all regions of the
specimen where the principal-stress directions are
aligned with those of the polarizer and analyzer will be
dark.
• The locus of such points is called an isoclinic because
the orientation, or inclination, of the maximum
principal normal stress direction is the same for all
points on this locus.
• By rotating both the analyzer and polarizer together (so
that they stay mutually crossed), isoclinics of various
principal-stress orientations can be mapped throughout
the plane.
4/4/2014 22Hareesha N G, Asst Prof,DSCE, Blore
23. Isochromatics
• The locus of points for which this condition is met is called an
isochromatic, because (except for n = 0) it is both stress and
wavelength dependent.
• Recall from Eqn. (7) that
4/4/2014 23Hareesha N G, Asst Prof,DSCE, Blore
24. • Therefore, points along an isochromatic in a plane polariscope satisfy
the condition
• The number n is called the order of the iso-chromatic.
• If monochromatic light is used, then the value of Δ is unique, and very
crisp isochromatics of very high order can often be photographed.
• However, if white light is used, then (except for n = 0), the locus of
points for which the intensity vanishes is a function of wavelength.
• For example, the locus of points for which red light is extinguished is
generally not a locus for which green or blue light is extinguished, and
therefore some combination of blue and green will be transmitted
wherever red is not.
• The result is a very colorful pattern, to be demonstrated by numerous
examples in class using a fluorescent light source
4/4/2014 24Hareesha N G, Asst Prof,DSCE, Blore