Aerospace Engineering 405

Aerospace Structural Design

Credit 3: (3-0)

Spring 2007

Instructor: Walter E. Haisler, Ph.D., P.E., Professor, Aerospace Engineering Dept.

Office: 719CH.R.BrightBuilding, phone: 845-1640, email: .

Course Web Page:

Office Hours: TR 8:30-10:00 am. Additional office hours by appointment (phone or email me, or contact Karen Knabe 845-5520). In general, I have an open door policy with regard to office hours.

Please note that I have other duties in the Dean of Engineering office, and hence my Office Hours may occasionally be changed.

TA: Deepak Goyal

Textbook: None. List of reference materials will be distributed to the class (list is also available on the course web page). Course notes used in the class are available on the course web page, and will usually be distributed to students.

Course Prerequisites: AERO 306.

Course Description: Overall structural integrity of complete aerospace systems; structures subject to critical loads; design considerations in aerospace structures.

Course Learning Goals/Objectives: This introductory course will teach you the basics of designing an aerospace structure using applicable theory, design methodology and computer tools. At the end of this course, students will be able to:

  1. Understand and determine loadings for typical aerospace vehicles; loads paths; understand aerospace material properties and be able select materials that satisfy design requirements (including metals and composite materials).
  2. Understand two- and three-dimensional finite element theory for structural analysis; understand the suitability and limitations of classical analysis techniques as well as finite element techniques.
  3. Apply a commercial finite element structural analysis code to the design of typical aircraft components such as a wing or fuselage, both individually and as a member of a team, and be able to critique and evaluate a finite element model of a structure, and be able to perform trade-off studies and optimization of a structural design to meet all design requirements,
  4. Understand linear plate theory, understand and be able to apply bucking theory to columns, flat plates and stiffened flat plates; understand and be able to apply composite laminate theory to the design of laminated flat plates.
  5. Synthesize all design requirements, necessary inputs, required theory and appropriate assumptions in order to solve real aerospace structural design problems in a computer-aided environment, both individually and as a team member, and present design results in both written and oral form.

Topics and Hours

Analysis/Design Skills & TopicsReferences, ToolsHours

1. Basic finite element method (FEM), FEMA&H, Reddy9

analysis/design tools and their use

2. Introduction to ABAQUS, Software: ABAQUS3

application to design of simple and

complex aerospace structures

3. Loads on aerospace structuresNiu, Mathcad, Maple, Matlab, etc.3

  • aerodynamic loadsAirfoil & finite wing software
  • inertial loads
  • thermal loads

4. Material properties (mechanical)Niu, Ashby5

allowables, toughness, fatigue, Sintech and Instron load frames

crack growth, selection procedures

5. Plate and shell analysisAllen & Haisler, Niu, handouts5

6. Composite laminate plate theoryJones, Gibson, Reddy, handouts6

and applicationscomposite laminate software

7. Design of monocoque & semimonocoqueNiu 4

structures (with isotropic andSoftware: ABAQUS

orthotropic materials)

8. Buckling: flat plates, curved platesNiu, Handouts5

cylinders, honeycomb & foam supportSintech and Instron load frames

9. Advanced selection of structural materialsAshby2

(metals, alloys & composites)

Total Hours42

Method of Evaluation. Your grade in this course will be based on the following:

1. Quizzes (15 minutes, approximately 7-10 quizzes)25%

2. Homework & several design projects (done individually or in teams)35%

3. Major design project and presentation (as a small team)40%

Contributions to Professional Component:

  1. Senior design elective.
  2. Builds on foundation in aerospace structures and materials established in the core subjects.
  3. Part of the required engineering topics portion of the curriculum. Helps prepare students for engineering practice.
  4. Prepares students to have knowledge of aerospace structural design, use of engineering tools to accomplish a design, and working in teams to complete a design project.

Relationship of Objectives to Program Outcomes:

Objectives / Assessment Method / ABET Outcome
Understand and determine loadings for typical aerospace vehicles; understand aerospace material properties and be able select materials that satisfy design requirements (including metals and composite materials). / Homework, mid-semester exam, and short design projects. / 3(a), 3(b), Aerospace Materials and Structures Program Criteria
Understand two- and three-dimensional finite element theory for structural analysis; understand the suitability and limitations of classical analysis techniques as well as finite element techniques. / Homework, mid-semester exam, and short design projects. / 3(a), 3(b), 3(e), 3(k), Aerospace Materials and Structures Program Criteria
Apply a commercial finite element structural analysis code to the design of typical aircraft components such as a wing or fuselage, both individually and as a member of a team. / Homework, mid-semester exam, short design projects, and major design project. / 3(a), 3(b) 3(c), 3(d), 3(e), 3(g), 3(k), Aerospace Materials and Structures Program Criteria
Understand linear plate theory, understand and be able to apply bucking theory to columns, flat plates and stiffened flat plates; understand and be able to apply composite laminate theory to the design of laminated flat plates. / Homework, mid-semester exam, and short design projects. / 3(a), 3(c), 3(e), 3(k), Aerospace Materials and Structures Program Criteria
Synthesize all design requirements, necessary inputs, required theory and appropriate assumptions in order to solve real aerospace structural design problems in a computer-aided environment, both individually and as a team member, and present design results in both written and oral form. / Major team design project. / 3(a), 3(b), 3(c), 3(d), 3(e), 3(f), 3(g), 3(k), Aerospace Materials and Structures Program Criteria

Attendance Policy, Self-Study, Homework, etc.: Students are expected to attend class! I also expect you to be on time. Engineers are required to practice “continuous” or “life-long” learning. You might as well get started on this notion of self-study now! We are going to be covering a lot of material in this class which will require you to do a lot of self-study, reading of handouts, reading of reference material, learning how to use software on your own, etc. Note that “Self” means you, not me (the instructor); it means taking the initiative on your own without anyone telling you. Project due dates will be strictly enforced. No excuses that you have something else that is due. Project completion by the due date is a part of learning time management and successful engineering practice.

Strategy for teaching and learning. This course will involve the introduction of a number of topics as listed below. I will provide brief introductions to the material in class, refer you to reference material, and provide handouts as appropriate. However, since you are a senior aerospace engineering student about to become a practicing engineer, I expect you spend considerable out-of-class time becoming familiar with the subject so that you can apply the theory, skills, etc. with suitable proficiency. I will not be assigning "make work" homework assignments for the sake of drilling you; rather, I expect you to take the initiative to do what ever reading, review of previous course material, practice drill, consultation with me, TA and other faculty, etc. that is required for you to learn the material. This is particularly important in areas that involve obtaining inputs, methodology, etc. to a design problem that are outside the traditional purview of "structures," e.g., aerodynamic loads, materials, stability and control, propulsion, integrated design, etc. Self-study and self-initiative are also important in learning to use tools like ABAQUS, and others; i.e., you must take the time to learn and practice with the tools if you expect to use them effectively in a design process. This is part of developing life-long learning skills and surviving in the real engineering world.

Attendance, Self-Study, Homework & Projects, Exams:

I expect you to take the opportunity to learn in this class. A part of learning is class attendance, outside reading, studying, doing homework, asking questions, and working in teams.

  • Teams - The class will be divided into teams of 2-4 engineers.
  • Attendance - Your attendance is warranted and expected. I also expect you to be on time. You can’t get much out of a class if you don’t attend! I realize that many of you have certain commitments to wind tunnel or flight testing schedules connected with AERO 402 which may conflict with this and other classes - these are inevitable and we can work around some of that. However, skipping AERO 405 or any other class in order to work on AERO 402, or any another class, is absolutely not acceptable. Don't believe me? - ask Carlson, Lund, Valasek or any of the other faculty.
  • Self-Study – Engineers are required to practice “continuous” or “life-long” learning. You might as well get started on this notion of self-study now! We are going to be covering a lot of material in this class which will require you to do a lot of self-study, reading of handouts, reading of reference material, lerning how to use software on your own, etc. Note that “Self” means you, not me (the instructor); it means taking the initiative on your own without anyone telling you. As I stated, you might as well get used to this notion of self-study now because your Boss is going to expect this behaviour, and it is imperative to your future success.
  • Homework & Projects - Projects (individual or as a team) will relate to the design and analysis of an aerospace structure (i.e., a wing, fuselage structure, or some structural component). You learn a lot more by “practicing” something as opposed to just reading, seeing or hearing it! Project due dates will be strictly inforced. No excuses that you have something else that is due. Project completion by the due date is a part of learning time management and successful engineering practice. In other words, Late homework and projects will be penalized 25% per day.
  • Major Project - Since the major project will span over perhaps half the semester, successful completion will require careful planning, time management, team participation, etc. THE MAJOR PROJECT WILL NOT BE ACCEPTED LATE.
  • Quizzes - Closed book, unannounced, one quiz about every 3-5 class periods, 15-20 minutes length.

Office Hours:

  • My office is generally open to students; however, please try to observe my office hours. Would you seriously think about going to see your doctor at a time he/she was not expecting you, or when you did not have an appointment? I doubt it. Walking into my office and asking “are you busy?” is a pretty dumb question!
  • If you make an appointment, please keep it. If you cannot keep an appointment, please notify me ASAP. How many of you would miss your doctor’s appointment? Think about it.
  • I use email a lot and will try to answer your questions as promptly as I can. But, please, please, don’t use email as a substitute for one-on-one, eyeball-to-eyeball interaction; seeing you face-to-face is much more effective as a teaching/learning process.

Email Addresses: In order for me to easily communicate with you at times other than our class time, I need for each of you to have a valid TAMU email address.

1)Your neo email account is considered the official communication line for university business.

2)I will use the bulk email function in neo to email the entire class when necessary. This can happen when several students are having trouble with an assignment, or with running the FEM code, or I failed to give you a critical piece of information, etc., then I will email the entire class so that you have information as soon as possible, and we don’t have to wait until the next class period to get important imformation.

3)Check your neo email once a day or so. Alternately, you can have neo forward your email to another account of your choice (aol, yahoo, msn, etc.)

Reference Material:

General

Introduction to Aerospace Structural Analysis, David H. Allen and Walter E. Haisler, McGraw-Hill.

Airframe Structural Design, Michael C. Y. Niu, Hong Kong Conmilit Press LTD, Second Edition, January 1999.

Airframe Stress Analysis and Design, Michael C. Y. Niu, Hong Kong Conmilit Press LTD, Second Edition, January 1999.

Airplane Design, 8 volume series, Jan Roskam, University of Kansas.

Analysis & Design of Flight Vehicle Structures, E. F. Bruhn, Tri-State Offset Company.

Roark's Formulas for Stress and Strain, Warren C. Young and Raymond J. Roark, 6th Edition, McGraw-Hill, 1989.

Composite Materials

Mechanics of Composite Materials, Robert M. Jones, McGraw-Hill, 1975.

Principles of Composite Material Mechanics, Ronald F. Gibson, McGraw-Hill, 1994.

Practical Analysis of Laminated Composite Structures, J.N. Reddy and A. Miravete, CRC Press, 1995.

Finite Element Analysis of Composite Laminates, O.O. Ochoa and J.N. Reddy, Klewer Academic Publishers, 1992.

Composite Airframe Structures, Michael C. Y. Niu, Hong Kong Conmilit Press LTD, Second Edition, 1993.

Fracuture Mechanics

Deformation and Fracture Mechanics of Engineering Materials, R.W. Hertzberg, Wiley, 1976.

Materials Selection

Materials Selection in Mechanical Design, Michael F. Ashby, Butterworth Hinemann, Second Edition, 1999.

FEM Theory/Analysis and Pre/Post ProcessingSoftware

An Introduction to the Finite element Method, J.N. Reddy, 2nd edition, McGraw-Hill, 1993.

+ scads of other FEM books dealing with theory and application

ABAQUS Software and examples

FEMAP & CAEFEM Software and examples

FEMAP and NxNastran Software and examples

Other Engineering Tools

Airfoil and finite wing analysis software

Composite laminate analysis software

Math & Programming Software Tools

Maple, MatLab, Mathcad, EES, Fortran

Notices:

Americans with Disabilities Act. The Americans with Disabilities Act (ADA) is a federal antidiscrimination statute that provides comprehensive civil rights protection for persons with disabilities. Among other things, this legislation requires that all students with disabilities be guaranteed a learning environment that provides for reasonable accommodation of their disabilities. If you believe you have a disability requiring an accommodation, please contact the Department of Student Life, Services for Students with Disabilities in Room 126 of the KoldusBuilding, or call 845-1637.

Copyrights. The handouts used in this course are copyrighted. By "handouts" we mean all materials generated for this class, which include but are not limited to syllabi, lab problems, in-class materials, courses handouts and other materials stored on the instructor’s web pages, review sheets, additional problem sets, or in any other form. Because these materials are copyrighted, you do not have the right to copy the handouts, unless the author expressly grants permission.

Scholastic Dishonesty. As commonly defined, plagiarism consists of passing off as one's own the ideas, work, writings, etc., that belong to another. In accordance with this definition, you are committing plagiarism if you copy the work of another person and turn it in as your own, even if you have the permission of that person. Plagiarism is one of the worst academic sins, for the plagiarist destroys the trust among colleagues without which research cannot be safely communicated. If you have questions regarding plagiarism, please consult the latest issue of the Texas A&M University Student Rules [ under the section "Scholastic Dishonesty."

SOME THOUGHTS FROM THE INSTRUCTOR (on learning and life):

I cannot teach you everything or show you the solution to every problem in the world; therefore, you must learn the basic principles and procedures andnotsolutions to specific problems.

Taking responsibility for your own actions, words and station-in-life allows you (forces you) to grow as a person.

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