For Video Lecture of this presentation: https://youtu.be/NAjezfbWh4Y
The topics covered in this session are, drag, categories of drag, drag polar equation and drag polar graph, drag polar derivation, induced drag coefficient.
Attention! "Gate Aerospace Engineering aspirants", A virtual guide for gate aerospace engineering is provided in "Age of Aerospace" blog for helping you meticulously prepare for gate examination. Respective notes of individual subjects are provided as 'Embedded Google Docs' which are frequently updated. This comprehensive guide is intended to efficiently serve as an extensive collection of online resources for "GATE Aerospace Engineering" which can be accessed free of cost. Use the following link to access the study material
https://ageofaerospace.blogspot.com/p/gate-aerospace.html
Structural detailing of fuselage of aeroplane /aircraft.PriyankaKg4
This presentation is about the structural detailing of fuselage of aeroplane .The fuselage or body of the airplane, holds all the pieces together. The pilots sit in the cockpit at the front of the fuselage. Passengers and cargo are carried in the rear of the fuselage. Some aircraft carry fuel in the fuselage; others carry the fuel in the wings.
For Video Lecture of this presentation: https://youtu.be/NAjezfbWh4Y
The topics covered in this session are, drag, categories of drag, drag polar equation and drag polar graph, drag polar derivation, induced drag coefficient.
Attention! "Gate Aerospace Engineering aspirants", A virtual guide for gate aerospace engineering is provided in "Age of Aerospace" blog for helping you meticulously prepare for gate examination. Respective notes of individual subjects are provided as 'Embedded Google Docs' which are frequently updated. This comprehensive guide is intended to efficiently serve as an extensive collection of online resources for "GATE Aerospace Engineering" which can be accessed free of cost. Use the following link to access the study material
https://ageofaerospace.blogspot.com/p/gate-aerospace.html
Structural detailing of fuselage of aeroplane /aircraft.PriyankaKg4
This presentation is about the structural detailing of fuselage of aeroplane .The fuselage or body of the airplane, holds all the pieces together. The pilots sit in the cockpit at the front of the fuselage. Passengers and cargo are carried in the rear of the fuselage. Some aircraft carry fuel in the fuselage; others carry the fuel in the wings.
Lecture slides on the calculation of the bending stress in case of unsymmetrical bending. The Mohr's circle is used to determine the principal second moments of area.
Aerodynamic characterisitics of a missile componentseSAT Journals
Abstract
A Missile is a self-propelled guided weapon system that travels through air or space. A powered, guided munitions that travels through the air or space is known as a missile (or guided missile). The Missile is defined as a space transversing unmanned vehicle that contains the means for controlling its flight path. The aerodynamic characteristics of a missile components such as body, wing and tail are calculated by using analytical methods to predict the drag and the normal forces of the missile. The total drag of the body is computed by using the parasite drag, wave drag, skin friction drag and base drag. The wing surface normal force coefficient (CN)Wing is a function of Mach number, local angle of attack, aspect ratio, and the wing surface plan form area (CN)Wing , based on the missile reference area, decreases with increasing supersonic Mach number and increases with angle of attack and the wing surface area. When the wing surface area is reduced the total weight of the missile and drag are reduced thereby increasing the lift and achieve excessive stability.
Keywords—Aerodynamics, drag, missile, normal forces and stability
Lecture slides on the calculation of the bending stress in case of unsymmetrical bending. The Mohr's circle is used to determine the principal second moments of area.
Aerodynamic characterisitics of a missile componentseSAT Journals
Abstract
A Missile is a self-propelled guided weapon system that travels through air or space. A powered, guided munitions that travels through the air or space is known as a missile (or guided missile). The Missile is defined as a space transversing unmanned vehicle that contains the means for controlling its flight path. The aerodynamic characteristics of a missile components such as body, wing and tail are calculated by using analytical methods to predict the drag and the normal forces of the missile. The total drag of the body is computed by using the parasite drag, wave drag, skin friction drag and base drag. The wing surface normal force coefficient (CN)Wing is a function of Mach number, local angle of attack, aspect ratio, and the wing surface plan form area (CN)Wing , based on the missile reference area, decreases with increasing supersonic Mach number and increases with angle of attack and the wing surface area. When the wing surface area is reduced the total weight of the missile and drag are reduced thereby increasing the lift and achieve excessive stability.
Keywords—Aerodynamics, drag, missile, normal forces and stability
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.
International Journal of Computational Engineering Research(IJCER) ijceronline
nternational Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
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.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
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Online aptitude test management system project report.pdfKamal Acharya
The purpose of on-line aptitude test system is to take online test in an efficient manner and no time wasting for checking the paper. The main objective of on-line aptitude test system is to efficiently evaluate the candidate thoroughly through a fully automated system that not only saves lot of time but also gives fast results. For students they give papers according to their convenience and time and there is no need of using extra thing like paper, pen etc. This can be used in educational institutions as well as in corporate world. Can be used anywhere any time as it is a web based application (user Location doesn’t matter). No restriction that examiner has to be present when the candidate takes the test.
Every time when lecturers/professors need to conduct examinations they have to sit down think about the questions and then create a whole new set of questions for each and every exam. In some cases the professor may want to give an open book online exam that is the student can take the exam any time anywhere, but the student might have to answer the questions in a limited time period. The professor may want to change the sequence of questions for every student. The problem that a student has is whenever a date for the exam is declared the student has to take it and there is no way he can take it at some other time. This project will create an interface for the examiner to create and store questions in a repository. It will also create an interface for the student to take examinations at his convenience and the questions and/or exams may be timed. Thereby creating an application which can be used by examiners and examinee’s simultaneously.
Examination System is very useful for Teachers/Professors. As in the teaching profession, you are responsible for writing question papers. In the conventional method, you write the question paper on paper, keep question papers separate from answers and all this information you have to keep in a locker to avoid unauthorized access. Using the Examination System you can create a question paper and everything will be written to a single exam file in encrypted format. You can set the General and Administrator password to avoid unauthorized access to your question paper. Every time you start the examination, the program shuffles all the questions and selects them randomly from the database, which reduces the chances of memorizing the questions.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
2. Course Objective
The purpose of the course is to
teach the principles of solid and
structural mechanics that can be
used to design and analyze
aerospace structures, in
particular aircraft structures.
5. Function of Aircraft Structures
General
The structures of most flight vehicles are thin walled
structures (shells)
Resists applied loads (Aerodynamic loads acting on the wing
structure)
Provides the aerodynamic shape
Protects the contents from the environment
6. Definitions
Primary structure:
A critical load-bearing structure on an aircraft.
If this structure is severely damaged, the
aircraft cannot fly.
Secondary structure:
Structural elements mainly to provide enhanced
aerodynamics. Fairings, for instance, are found
where the wing meets the body or at various
locations on the leading or trailing edge of the
wing.
11. Function of Aircraft Structures:
Part specific
Skin
reacts the applied torsion and shear forces
transmits aerodynamic forces to the longitudinal
and transverse supporting members
acts with the longitudinal members in resisting the
applied bending and axial loads
acts with the transverse members in reacting the
hoop, or circumferential, load when the structure is
pressurized.
12. Function of Aircraft Structures:
Part specific
Ribs and Frames
1. Structural integration of the wing and fuselage
2. Keep the wing in its aerodynamic profile
13. Function of Aircraft Structures:
Part specific
Spar
1. resist bending and axial loads
2. form the wing box for stable torsion resistance
14. Function of Aircraft Structures:
Part specific
Stiffener or Stringers
1. resist bending and axial loads along with the skin
2. divide the skin into small panels and thereby
increase its buckling and failing stresses
3. act with the skin in resisting axial loads caused
by pressurization.
15. Simplifications
1. The behavior of these structural elements is often
idealized to simplify the analysis of the assembled
component
2. Several longitudinal may be lumped into a
single effective
3. longitudinal to shorten computations.
4. The webs (skin and spar webs) carry only shearing
stresses.
5. The longitudinal elements carry only axial stress.
6. The transverse frames and ribs are rigid within
their own planes, so that the cross section is
maintained unchanged during loading.
16. UNIT-I
Unsymmetric Bending of
Beams
The learning objectives of this chapter are:
•Understand the theory, its limitations, and
its application in design and analysis of
unsymmetric bending of beam.
17. UNIT-I
UNSYMMETRICAL BENDING
The general bending stress equation for elastic, homogeneous beams is given as
where Mx and My are the bending moments about the x and y centroidal axes,
respectively. Ix and Iy are the second moments of area (also known as
moments of inertia) about the x and y axes, respectively, and Ixy is the product
of inertia. Using this equation it would be possible to calculate the bending
stress at any point on the beam cross section regardless of moment orientation
or cross-sectional shape. Note that Mx, My, Ix, Iy, and Ixy are all unique for a
given section along the length of the beam. In other words, they will not
change from one point to another on the cross section. However, the x and y
variables shown in the equation correspond to the coordinates of a point on the
cross section at which the stress is to be determined.
(II.1)
18. Neutral Axis:
When a homogeneous beam is subjected to elastic bending, the neutral axis
(NA) will pass through the centroid of its cross section, but the orientation of the
NA depends on the orientation of the moment vector and the cross sectional
shape of the beam.
When the loading is unsymmetrical (at an angle) as seen in the figure below, the
NA will also be at some angle - NOT necessarily the same angle as the bending
moment.
Realizing that at any point on the neutral axis, the bending strain and stress
are zero, we can use the general bending stress equation to find its
orientation. Setting the stress to zero and solving for the slope y/x gives
(
19. UNIT-II
SHEAR FLOW AND SHEAR CEN
Restrictions:
1. Shear stress at every point in the beam must be less than the
elastic limit of the material in shear.
2. Normal stress at every point in the beam must be less than the elastic
limit of the material in tension and in compression.
3. Beam's cross section must contain at least one axis of symmetry.
4. The applied transverse (or lateral) force(s) at every point on the beam
must pass through the elastic axis of the beam. Recall that elastic axis
is a line connecting cross-sectional shear centers of the beam. Since
shear center always falls on the cross-sectional axis of symmetry, to
assure the previous statement is satisfied, at every point the
transverse force is applied along the cross-sectional axis of symmetry.
5. The length of the beam must be much longer than its cross sectional
dimensions.
6. The beam's cross section must be uniform along its length.
20. Shear Center
If the line of action of the force passes through the
Shear Center of the beam section, then the beam
will only bend without any twist. Otherwise, twist will
accompany bending.
The shear center is in fact the centroid of the internal
shear force system. Depending on the beam's cross-
sectional shape along its length, the location of shear
center may vary from section to section. A line
connecting all the shear centers is called the elastic
axis of the beam. When a beam is under the action of
a more general lateral load system, then to prevent
the beam from twisting, the load must be centered
along the elastic axis of the beam.
21. Shear Center
The two following points facilitate the determination of the shear center
location.
1. The shear center always falls on a cross-sectional axis of symmetry.
2. If the cross section contains two axes of symmetry, then the shear center is
located at their intersection. Notice that this is the only case where shear
center and centroid coincide.
24. EXAMPLES
For the beam and loading shown, determine:
(a) the location and magnitude of the maximum transverse shear force 'Vmax',
(b) the shear flow 'q' distribution due the 'Vmax',
(c) the 'x' coordinate of the shear center measured from the centroid,
(d) the maximun shear stress and its location on the cross section.
Stresses induced by the load do not exceed the elastic limits of the material. NOTE:In this problem
the applied transverse shear force passes through the centroid of the cross section, and not its
shear center.
FOR ANSWER REFER
http://www.ae.msstate.edu/~masoud/Teaching/exp/A14.7_ex3.html
25. Shear Flow Analysis for
Unsymmetric Beams
SHEAR FOR EQUATION FOR UNSUMMETRIC SECTION IS
26. SHEAR FLOW DISTRIBUTION
For the beam and loading shown, determine:
(a) the location and magnitude of the maximum
transverse shear force,
(b) the shear flow 'q' distribution due to 'Vmax',
(c) the 'x' coordinate of the shear center measured
from the centroid of the cross section.
Stresses induced by the load do not exceed the
elastic limits of the material. The transverse shear
force is applied through the shear center at every
section of the beam. Also, the length of each member
is measured to the middle of the adjacent member.
ANSWER REFER
http://www.ae.msstate.edu/~masoud/Tea
ching/exp/A14.8_ex1.html
27. Beams with Constant Shear Flow
Webs
Assumptions:
1. Calculations of centroid, symmetry, moments of
area and moments of inertia are based totally on
the areas and distribution of beam stiffeners.
2. A web does not change the shear flow between two
adjacent stiffeners and as such would be in the state
of constant shear flow.
3. The stiffeners carry the entire bending-induced
normal stresses, while the web(s) carry the entire
shear flow and corresponding shear stresses.
28. Analysis
Let's begin with a simplest thin-walled stiffened beam. This means a beam with
two stiffeners and a web. Such a beam can only support a transverse force that
is parallel to a straight line drawn through the centroids of two stiffeners.
Examples of such a beam are shown below. In these three beams, the value of
shear flow would be equal although the webs have different shapes.
The reason the shear flows are equal is that the distance between two adjacent
stiffeners is shown to be 'd' in all cases, and the applied force is shown to be
equal to 'R' in all cases. The shear flow along the web can be determined by the
following relationship
29. Important Features of
Two-Stiffener, Single-Web Beams:
1. Shear flow between two adjacent stiffeners is constant.
2. The magnitude of the resultant shear force is only a function of the
straight line between the two adjacent stiffeners, and is absolutely
independent of the web shape.
3. The direction of the resultant shear force is parallel to the straight line
connecting the adjacent stiffeners.
4. The location of the resultant shear force is a function of the enclosed
area (between the web, the stringers at each end and the arbitrary
point 'O'), and the straight distance between the adjacent stiffeners.
This is the only quantity that depends on the shape of the web
connecting the stiffeners.
5. The line of action of the resultant force passes through the shear
center of the section.
30. EXAMPLE
For the multi-web, multi-stringer open-section beam shown, determine
(a) the shear flow distribution,
(b) the location of the shear center
Answer
31. UNIT-III
Torsion of Thin - Wall Closed
Sections
Derivation
Consider a thin-walled member with a closed cross section subjected to pure torsion.
34. Angle of Twist
By applying strain energy equation due to shear and
Castigliano's Theorem the angle of twist for a thin-
walled closed section can be shown to be
Since T = 2qA, we have
If the wall thickness is constant along each segment of
the cross section, the integral can be replaced by a
simple summation
35. Torsion - Shear Flow Relations in Multiple-
Cell Thin- Wall Closed Sections
The torsional moment in terms of the internal
shear flow is simply
36. Derivation
For equilibrium to be maintained at a exterior-interior wall (or web)
junction point (point m in the figure) the shear flows entering
should be equal to those leaving the junction
Summing the moments about an arbitrary point O, and assuming clockwise
direction to be positive, we obtain
The moment equation above can be simplified to
37. Shear Stress Distribution and Angle of
Twist for Two-Cell Thin-Walled Closed
Sections
The equation relating the shear flow along the exterior
wall of each cell to the resultant torque at the section is given as
This is a statically indeterminate problem. In order
to find the shear flows q1 and q2, the compatibility
relation between the angle of twist in cells 1 and 2 must be used. The compatibility
requirement can be stated as
where
38. The shear stress at a point of interest is found according to the
equation
To find the angle of twist, we could use either of the two twist formulas
given above. It is also possible to express the angle of twist equation
similar to that for a circular section
39. Shear Stress Distribution and Angle of Twist for
Multiple-Cell Thin-Wall Closed Sections
In the figure above the area outside of the cross section will be designated as
cell (0). Thus to designate the exterior walls of cell (1), we use the notation 1-
0. Similarly for cell (2) we use 2-0 and for cell (3) we use 3-0. The interior walls
will be designated by the names of adjacent cells.
the torque of this multi-cell member can be related to the shear flows in exterior
walls as follows
40. For elastic continuity, the angles of twist in all
cells must be equal
The direction of twist chosen to be positive is clockwise.
42. EXAMPLE
For the thin-walled single-cell rectangular beam and loading shown, determine
(a) the shear center location (ex and ey),
(b) the resisting shear flow distribution at the root section due to the applied load
of 1000 lb,
(c) the location and magnitude of the maximum shear stress
ANSWER REFER
http://www.ae.msstate.edu/~masoud/Teaching/exp/A15.2_ex1.html