Mechanical Engineering homework help

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Need help to prepare the attached project professionally before the due date.
mechanical engineering filed.

Topics Covered:

1.  Combustion process in the Spark-Ignition Engine.
2. Vapor Compression Refrigeration System
3. Combustion Process and Thermal Efficiency of Diesel Engines
4. Vapor Absorption Refrigeration System by Solar Energy

MEC352 –Thermodynamics II
Fall 2020
Group Design Project (4 members)
Due 5:00 p.m., 13/12/2020
 

Topics Covered:

1. Combustion Process in the Spark-Ignition Engine

  1. Vapor Compression Refrigeration System
  2. Combustion Process and Thermal Efficiency of Diesel Engines
  3. Vapor Absorption Refrigeration System by Solar Energy

 
 

Write-up:

Your report should have the following sections:
Introduction, theoretical analysis, design, results and discussion, and summary
 
Include the following in your write-up:

  • Develop a detailed thermal model.
  • Justify all equations and
  • Discuss why this general design was
  • Discuss design specifics and
  • Show why your design is
  • Cite with reputable sources (i.e. not Wikipedia, ).
  • Include any code used for the analysis in the appendices, such as Excel, Matlab,
  • Include detailed drawings for accurate reproduction of your thermodynamics analysis.

 
Grading note: Group participation will be taken

Mechanical Engineering homework help

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Analysis and Design of a Tracked Vehicle Suspension Arm

AME3143.001 SOLID MECHANICS
Fall 2020
Project #2: Analysis and Design of a Tracked Vehicle Suspension Arm
(100 points)
Assigned: Monday, November 9, 2020
Due: 5:45PM, Sunday, December 6, 2020
Please submit ONE PDF REPORT to the Project#2 Dropbox on Canvas before 5:45PM, Sunday,
December 6, 2020
Please read the following statements VERY carefully:
1. No late submission will be graded, no email submission will be accepted.
2. All reports must place a complete academic integrity pledge form (per Page 3 of the course syllabus)
as a cover page. A report without a pledge form, or with an incorrect or incomplete pledge form will
not be graded. The form must be signed and dated, and state who you work with and the aids you
received or offered. No resubmission or amended form after the due date will be accepted. NO
PLEDGE NO CREDIT.
3. Please do not engage in activities that cross the line of committing academic misconduct. Those who
received inadequate aids from or offered inadequate aids to others receive zero credit and will be
reported to OU Office of Academic Integrity Programs.
4. Please do not hesitate to bring questions to Dr. Chang or Anirban for clarifications. Only
clarifications to the project assignment will be offered. Questions regarding how to approach the
problem or how to carry out calculations are part of the assignment; therefore, will not be answered.
Please do not suggest a different object or part in place of the suspension arm. Please do not suggest a
different project to work on.
Project Statement: Project#2 involves analysis and redesign of a tracked vehicle suspension arm, as
shown in Figure 1. The large end (upper left) of the arm is tightly fit to a torsion bar of the tracked vehicle
suspension, and the other end connects to the shaft of a roadwheel. A suspension arm carries major load
of the vehicle while maneuvering in a bumpy terrain. The load is transmitted from the roadwheel through
the suspension arm to the torsion bar of the vehicle suspension. The load acting on the arm is a vertical
force coming from the roadwheel at the load application point shown in Figure 2. Also shown in Figure 2
are sketches of the suspension arm in two views with major dimensions and geometric shape. The
distance between the centers of the holes at the large (left) and right ends is 20 in. The cross-sectional area
of the arm is composed of two circular arcs of radius R = 0.75 in. and four straight lines. The distance
between the two arc centers is 1.75 in. at Section AA’ and 1.5 in. at Section BB’. In between, the arm is
linearly tapered along the x2-direction, as seen on the x2-x3 plane. The width of the cross section is 2 in.
The distance along the x1-direction between the two hole centers is 4.5 in. as seen on the x1-x2 plane. The
distance between the center of the hole at the right end and roadwheel where the load is applied is 4.0 in.
The suspension arm is made of AISI 1030 HR steel.
Figure 1 Suspension arm of a tracked vehicle
Figure 2 Major dimensions and geometric shape of the suspension arm
As stated above, the hole at the left end of the suspension arm is tightly fit to a torsion bar, and the hole at
its right end connects to the roadwheel shaft. When the tracked vehicle is not moving, the suspension arm
rests at a clockwise 30-degree angle measured from a horizontal line, as shown in Figure 3. While
maneuvering, the arm swings to an angle no less than 15 degrees.
o
30
Figure 3 Suspension arm at a rest position
In this project, you are asked to conduct stress analysis and redesign for the suspension arm. The project
involves:
(1) Carrying out stress analysis to identify the arm swing angle (greater than 15 degrees) where the arm
experiences a maximum stress (must include all component stresses present; i.e., axial, bending, and
torsion).
(2) Based on the finding in (1), calculate the maximum allowable force acting on the arm coming from
the roadwheel for a safety factor of 2.
(3) If the maximum allowable force obtained in (2) is increased by 10%, redesign the suspension arm that
maintains a safety factor 2 without increasing its weight.
Project Report: A report of no more than three pages must be submitted for grading before the due date
stated above. Graphs, tables, and data can be arranged in appendices. Appendices are not counted for the
page limit. The format and style of the report must conform to the report template provided in Project#1
assignment (CADandA_Newtemplate.doc) and must include the following:
(1) A short abstract that provides an overview and key findings of the project;
(2) A short introduction to summarize the engineering assignment;
(3) Your overall step-by-step approach;
(4) Assumptions (if any) you made for your analysis;
(5) Your calculations;
(6) Outcome and justification. Why your outcome is useful and reliable?
(7) Summary and lessons learned;
(8) References (if any).
Grading Criteria: The following is how your report will be graded by Dr. Chang and Anirban. In each
category listed below, the best work receive full credits, and the worse work receive zero point. In
between, points are assigned roughly proportionally depending on the accuracy, clarity, quality, and level
of effort of the work presented.
(1) How well and realistic is your approach in addressing the engineering problem (5%)
(2) How realistic and logical are the assumptions you made (5%)
(3) Free-body diagram and stress calculations (15%)
(4) The arm swing angle at the maximum stress (10%)
(5) The maximum allowable force calculated (10%)
(6) Re-designed arm (15%)
(7) Outcome and justifications (15%)
(8) Lessons learned (5%)
(9) Overall quality of the report (20%)
Please note that the points awarded following this approach is somehow subjective. Therefore, please
offer as detailed and as complete information as possible in your report so as that you earn highest points
possible. Your calculations must be presented clearly with adequate illustrations and explanations.
Calculations that are not clear and difficult to follow will receive a minimum, or in some cases, zero
credit.
Please note that Project#2 is a typical engineering assignment you will be given as a journeyman
engineer. In your report, you must not only show accurate engineering calculations but also demonstrate
sound engineering proficiency in presenting your work at a near-professional level.
PRIZE FOR THE BEST PROJECT WINNER(S):
• A certification letter from Dr. Chang for the winner(s) to keep and to show off
• A textbook of your choice (~$60 each, see below):

Mechanical Engineering homework help

/in /by

AME3143.001 SOLID MECHANICS
Fall 2020
Project #2: Analysis and Design of a Tracked Vehicle Suspension Arm
(100 points)
Assigned: Monday, November 9, 2020
Due: 5:45PM, Sunday, December 6, 2020
Please submit ONE PDF REPORT to the Project#2 Dropbox on Canvas before 5:45PM, Sunday,
December 6, 2020
Please read the following statements VERY carefully:
1. No late submission will be graded, no email submission will be accepted.
2. All reports must place a complete academic integrity pledge form (per Page 3 of the course syllabus)
as a cover page. A report without a pledge form, or with an incorrect or incomplete pledge form will
not be graded. The form must be signed and dated, and state who you work with and the aids you
received or offered. No resubmission or amended form after the due date will be accepted. NO
PLEDGE NO CREDIT.
3. Please do not engage in activities that cross the line of committing academic misconduct. Those who
received inadequate aids from or offered inadequate aids to others receive zero credit and will be
reported to OU Office of Academic Integrity Programs.
4. Please do not hesitate to bring questions to Dr. Chang or Anirban for clarifications. Only
clarifications to the project assignment will be offered. Questions regarding how to approach the
problem or how to carry out calculations are part of the assignment; therefore, will not be answered.
Please do not suggest a different object or part in place of the suspension arm. Please do not suggest a
different project to work on.
Project Statement: Project#2 involves analysis and redesign of a tracked vehicle suspension arm, as
shown in Figure 1. The large end (upper left) of the arm is tightly fit to a torsion bar of the tracked vehicle
suspension, and the other end connects to the shaft of a roadwheel. A suspension arm carries major load
of the vehicle while maneuvering in a bumpy terrain. The load is transmitted from the roadwheel through
the suspension arm to the torsion bar of the vehicle suspension. The load acting on the arm is a vertical
force coming from the roadwheel at the load application point shown in Figure 2. Also shown in Figure 2
are sketches of the suspension arm in two views with major dimensions and geometric shape. The
distance between the centers of the holes at the large (left) and right ends is 20 in. The cross-sectional area
of the arm is composed of two circular arcs of radius R = 0.75 in. and four straight lines. The distance
between the two arc centers is 1.75 in. at Section AA’ and 1.5 in. at Section BB’. In between, the arm is
linearly tapered along the x2-direction, as seen on the x2-x3 plane. The width of the cross section is 2 in.
The distance along the x1-direction between the two hole centers is 4.5 in. as seen on the x1-x2 plane. The
distance between the center of the hole at the right end and roadwheel where the load is applied is 4.0 in.
The suspension arm is made of AISI 1030 HR steel.
Figure 1 Suspension arm of a tracked vehicle
Figure 2 Major dimensions and geometric shape of the suspension arm
As stated above, the hole at the left end of the suspension arm is tightly fit to a torsion bar, and the hole at
its right end connects to the roadwheel shaft. When the tracked vehicle is not moving, the suspension arm
rests at a clockwise 30-degree angle measured from a horizontal line, as shown in Figure 3. While
maneuvering, the arm swings to an angle no less than 15 degrees.
o
30
Figure 3 Suspension arm at a rest position
In this project, you are asked to conduct stress analysis and redesign for the suspension arm. The project
involves:
(1) Carrying out stress analysis to identify the arm swing angle (greater than 15 degrees) where the arm
experiences a maximum stress (must include all component stresses present; i.e., axial, bending, and
torsion).
(2) Based on the finding in (1), calculate the maximum allowable force acting on the arm coming from
the roadwheel for a safety factor of 2.
(3) If the maximum allowable force obtained in (2) is increased by 10%, redesign the suspension arm that
maintains a safety factor 2 without increasing its weight.
Project Report: A report of no more than three pages must be submitted for grading before the due date
stated above. Graphs, tables, and data can be arranged in appendices. Appendices are not counted for the
page limit. The format and style of the report must conform to the report template provided in Project#1
assignment (CADandA_Newtemplate.doc) and must include the following:
(1) A short abstract that provides an overview and key findings of the project;
(2) A short introduction to summarize the engineering assignment;
(3) Your overall step-by-step approach;
(4) Assumptions (if any) you made for your analysis;
(5) Your calculations;
(6) Outcome and justification. Why your outcome is useful and reliable?
(7) Summary and lessons learned;
(8) References (if any).
Grading Criteria: The following is how your report will be graded by Dr. Chang and Anirban. In each
category listed below, the best work receive full credits, and the worse work receive zero point. In
between, points are assigned roughly proportionally depending on the accuracy, clarity, quality, and level
of effort of the work presented.
(1) How well and realistic is your approach in addressing the engineering problem (5%)
(2) How realistic and logical are the assumptions you made (5%)
(3) Free-body diagram and stress calculations (15%)
(4) The arm swing angle at the maximum stress (10%)
(5) The maximum allowable force calculated (10%)
(6) Re-designed arm (15%)
(7) Outcome and justifications (15%)
(8) Lessons learned (5%)
(9) Overall quality of the report (20%)
Please note that the points awarded following this approach is somehow subjective. Therefore, please
offer as detailed and as complete information as possible in your report so as that you earn highest points
possible. Your calculations must be presented clearly with adequate illustrations and explanations.
Calculations that are not clear and difficult to follow will receive a minimum, or in some cases, zero
credit.
Please note that Project#2 is a typical engineering assignment you will be given as a journeyman
engineer. In your report, you must not only show accurate engineering calculations but also demonstrate
sound engineering proficiency in presenting your work at a near-professional level.
PRIZE FOR THE BEST PROJECT WINNER(S):
• A certification letter from Dr. Chang for the winner(s) to keep and to show off
• A textbook of your choice (~$60 each, see below):

Mechanics homework help

/in /by
brief written statements containing main conceptual ideas from the assigned reading material in your own words, accompanied by three written questions you would like to be answered in the class
Chapter 3: Operators and observables 3.3.1 –3.3.2- 3.3.3 this is together than writing three questions
Angular momentum operator and statistical interpretation. 3.3.4, 3.3.5 this is together than writing three questions
chapter 4: 4.1.1 – 4.1.2  this is together than writing three questions

Advance Materials

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PART – I 
 
(i) Cylindrical shaped pressure vessel with both ends opened

  • Translation of problem indicating function, objective, constraints and free variables?

(3 marks)
 

  • Derive the performance material index for failure.

(7 marks)

 
(c) Discuss the implication of two performance index i.e., due to yielding and fast fracture for the selection of one material. Find the coupling line by making equal the cost calculated with the two indexes.

(4 marks)

 
(d) Use CES EDUPack (Rebranded as GRANTA EDUPACK 2020) to create a graph representing the material index and identify the region of the chart with the cheapest materials for the pressure vessel due to yielding and fast fracture material index.
 
[Hint 1]: Use the concept of coupling line for selecting best material materials for the cylindrical pressure vessel due to yielding and fast fracture material index.  
(6 marks)
PART – II 
 

(ii) Spherical shaped pressure vessel

 
(e) Translation of problem indicating function, objective, constraints and free variables?
(3 marks)  (f) Derive the performance material index for failure.

(7 marks)

 
(g) Use CES Edupack (Rebranded as GRANTA EDUPACK 2020) to create a graph representing the material index and identify the region of the chart with the cheapest materials for the for the pressure vessel due to fast fracture material index.

(5 marks)

 
Reminder, as it is an open exercise, each student is expected to have a unique solution as definition of the problem will be unique.
 (Total: 35 marks)
 
QUESTION 2

PART – I

 
A truck manufacturing company wants to design a new material for the springs used in the heavy loaded trucks (Figure Q – 2). In vehicle suspension design it is desirable to minimize the mass of all components and select a material as cheap as possible. You have been asked to select a material and dimensions for a light spring to replace the steel leaf-spring of an existing truck suspension. You need to decide the structure of the existing leaf-spring. The new spring must have the same length, L and stiffness, S as the existing one, and must deflect through a maximum safe displacement, δmax without failure.
 
 

Figure Q – 3 : Vehicle suspension system

 
You will need to decide extra constraints and find out the necessary equations to solve the springs for truck application. You will need to decide your objective and to compare the results with real world materials. You will need to translate the problem, derive the performance index or indexes, coupling line between the performance index and select some screening constraint.
 
[Hint 1]: You will have to decide your own dimensions for the selected structure and the constraints.
You have to document the whole selection process.

  • Definition of the problem
    • marks)
  • Translation of the problem
    • marks)
  • Derive performance index

(8 marks)
 

  • Use CES Edupack (Rebranded as GRANTA EDUPACK 2020) to create a graph representing the material index and identify the region of the chart with the cheapest materials for the leaf spring.

 (6 marks)

PART – II

Most of the springs are made of high strength alloy steel, and they are heavy. You are asked to explore the potential of alternative materials for lighter springs, recognizing there must be a trade-off between mass and cost – if it is too expensive, the manufacturing company will not want it even if it is lighter.
Show that the mass and material cost of the spring relative to one made of high strength alloy steel is given by
𝐦𝐦 = (𝐄𝛔 𝐱 𝛒) ( ,𝟎𝟐 ) and 𝐂 = (𝐄 𝐱 𝐂𝐦𝟐 𝐱 𝛒)(𝐄𝟎 𝐱 𝛔𝐂𝐟𝐦,𝟎,𝟎𝟐 𝐱 𝛒𝟎)
𝟐 𝟎                    𝐟                      𝐄𝟎 𝐱 𝛒𝟎        𝐂𝟎                   𝛔𝐟
 
where ρ is the density, σf the failure strength and Cm the cost per kg of the material, and the subscript “o” indicates values for high strength alloy steel.
 
[Hint 2]: Use the ratio for new material over the steel.                                                                          
𝑚
= 𝑚𝑎𝑠𝑠 𝑟𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝑡𝑜 ℎ𝑖𝑔ℎ 𝑠𝑡𝑟𝑒𝑛𝑔𝑡ℎ 𝑎𝑙𝑙𝑜𝑦 𝑠𝑡𝑒𝑒𝑙 
𝑚0
and   = 𝑐𝑜𝑠𝑡 𝑟𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝑡𝑜 ℎ𝑖𝑔ℎ 𝑠𝑡𝑟𝑒𝑛𝑔𝑡ℎ 𝑎𝑙𝑙𝑜𝑦 𝑠𝑡𝑒𝑒𝑙.  𝐶0
 

  • Show that the mass and material cost of the spring relative to one made of high strength alloy steel is given by

𝐦𝐦𝟎 = (𝐄𝛔 𝐱𝐟𝟐 𝛒) (𝐄𝛔𝟎𝐟 𝐱, 𝛒𝟐𝟎) and 𝐂𝐂 = (𝐄 𝐱 𝛔𝐂𝐟𝐦𝟐 𝐱 𝛒)(𝐄 𝐱 𝛔𝐂𝐟𝐦,𝟎,𝟎𝟐 𝐱 𝛒𝟎)
𝟎                                                       𝟎
(2 marks)
 
 

  • Explore the trade-off between relative cost and relative mass. Sketch a trade-off surface. Define a relative penalty function.

(6 marks)
Reminder, as it is an open exercise, each student is expected to have a unique solution as definition of the problem will be unique.
 (Total: 30 marks)
 

QUESTION 3

 

  • Draw the Time Temperature Transformation T-T-T diagram for Aluminium – Copper

(Al – 4 % Cu) alloys and show on the diagram the critical cooling curve, the transformation lines, the phases and the axis.
(4 marks)
 

  • Explain the change of structure with martensitic transformation of steels.

(2 marks)

 
(c) The copper-tin system (which includes bronzes) is shown in the Figure Q – 3 below
 

Figure Q – 3: Copper – Tin phase diagram

Note: Use the Annexure 1 for calculations
 

  • List and mark out the single phase regions;

(2 marks)

  • Highlight the four eutectoids in the copper-tin system,

(2 marks)

  • List out the compositions and temperatures of the eutectoids.

(4 marks)
 

  • Discuss with help of simple sketch along with an example of the phase diagram (binary system) in which PERITECTIC REACTION AND PERITECTIC

POINT, reaction occur during the phase transformation of metals. Describe the phase reaction and the corresponding temperature for the selected example.
(2 marks)
 
(Total for part (c) : 10 marks)
 
(d) Compare and contrast the main features of diffusive and displacive transformations during structural changes in metals.
(4 marks)
 
(Total: 20 marks)

QUESTION 4

Houses in UK uses cast iron or steel guttering and this gutter material is prone to corrosion over time as shown in Figure Q – 4.

  • To prevent the mild sheet-steel guttering from corrosion it is copper-plated and the guttering acts as a drain for sea water. If the coating is damaged, exposing the steel, will the guttering corrode in a damaging way?
  • If instead the guttering is zinc-plated, will it be better or less well protected?

Suggest the mechanism of corrosion taking place in these two types of coating on the mild sheet-steel guttering.
 
Figure Q – 4: Corrosion of steel gutter
(Total: 5 marks)

QUESTION 5

 

  • Using suitable examples, explain the meaning of dislocation movement in metals. Explain with simple sketches different types of dislocation in relation to metals.
    • marks)
  • Using suitable industrial examples, explain creep in metals. Comment and contract dislocation movement in both plastic deformation and in creep.