16.242 Aeroelasticity (Fall
'99) | |

Personnel | |

Prof. Carlos E. S. Cesnik (instructor) 33-313 x2-1518 ccesnik@mit.edu Ms. Cathy Chase (course secretary) 33-309 x3-6339 cmchase@mit.edu | |

Classes | |

Tuesday and Thursday 9:30-11:00 Rm. 33-418 | |

Course Prerequisites | |

The student is expected to be familiar with free vibration modes, normal coordinates, response of multimass and continuous systems, and variational principles in dynamics: Hamilton Principle and Lagrange's equations (as presented in 16.221). | |

Course Objectives/Philosophy | |

This course will address issues related to the mutual interaction of elastic, inertial, and aerodynamic forces with emphasis on aeronautical applications. It builds on basic material presented in 16.221 and introduces students to the concepts and tools used in unsteady aerodynamics. It is intended that the student will become familiar with the important issues and philosophies associated with aeroelastic stability and response, will become conversant in the terminology of aeroservoelasticity, and will achieve a working understanding of these issues applied to various aeronautical systems. | |

Textbooks | |

The two main references for this subject are: *A Modern**Course*in*Aeroelasticity*by Dowell, Crawley, Curtiss Jr., Peters, Scanlan, and Sisto, Kluwer Academic Publishers, 3rd Edition, 1995.*Aeroelasticity*, by Bisplinghoff, Ashley, and Halfman, Dover, 1955.
Complementary, a list of references related to the course material is provided, and some of them are on reserve in the Aero & Astro Library. The notes taken from the lectures supplemented with handouts should serve as an excellent reference. | |

Course Requirements/Grading | |

There will be two types of assignments during the term: problem sets and quizzes. No final exam is scheduled for this subject. There will be approximately six problem sets during the term. These will be handed out on a relatively regular basis and generally have a one week period for completion. It is expected that the assignments will be handed in on time. Late submission should be explained to the faculty member in charge of the course and will generally be penalized. There will be two quizzes during the term. The first will be an in-class exam at approximately mid-term, and the second will be a take-home exam at the end of the term. Several days will be given for the completion of the exam. The exact hand-out and due dates will be announced at least two weeks prior to the exams. Regarding the presentation of information in general (on quizzes and problem sets), the clarity and "neatness" of it are very important for this class as they are for the engineers' professional life. For the assignments that involve the use of computer programming, the printouts should be attached but they will not count as a source of key information to the solution of the given assignment. The final grade will be calculated approximately as follows: - Problem sets 60%
- Quizzes 40%
for a total of 100%. Attendance, participation, general evaluation ±5% The course will be graded on an absolute scale using the letter grades as defined in the MIT Faculty Rules and Regulations: A - Exceptionally good performance, demonstrating a B - Good performance, demonstrating capacity to use the appropriate concepts,
a C - Adequate performance, demonstrating an D - Minimally acceptable performance, demonstrating at least F - Unsatisfactory performance. Plusses and minuses will be used in conjunction with the letters in grading term-time work. The final grade will not include plusses or minuses. | |

Office Hours | |

The main time for off-class discussions is the hour immediately after class (at 11:00 am). Professor Cesnik can also be consulted by appointment. | |

Syllabus/Schedule | |

The topics to be covered during the term will deal with static and dynamic
aeroelastic stability and response, and unsteady aerodynamics for fixed-wing
aircraft. Several aspects of the aeroelastic problem will also be explored
for helicopters, HALE vehicles, and wind tunnel tests. Finally, aeroservoelasticity
will be presented as a mean of modifying the aeroelastic behavior of the
system by introduction of control forces. A post factum syllabus
will be handed out at the end of the term. | |

Academic Honesty | |

It is expected that the submission of each student represents the work of that, and only that, individual student. Students should feel free to consult each other, as well as the course faculty, in developing solutions to problem sets. However, it is expected that the final submission represents the effort of only that student. No consultation with fellow students is allowed on the take-home examinations. Any material used from another source or person must be properly referenced. An individual engineer/reviewer/researcher does not need to come up with all the ideas. In fact, a good engineer knows how to incorporate the good ideas and thoughts of others. However, it is essential to "give credit where credit is due". Cases of academic dishonesty are a severe breach of the student's and engineer's codes and will be treated appropriately. | |

References | |

## Main References:- Dowell, E. H., Crawley, E. F., Curtiss Jr., H. C., Peters, D. A., Scanlan,
R. H., and Sisto, F.,
*A Modern Course in Aeroelasticity*, Kluwer Academic Publishers, 3rd Edition, 1995. (TL574.A37.M62) - Bisplinghoff, R., Ashley, H., and Halfman, R. L.,
*Aeroelasticity*, Dover, 1955. (TL570.B622) - Bisplinghoff, R. and Ashley, H.,
*Principles of Aeroelasticity*, Dover, 1962. (TL570.B623)
## Others:- Fung, Y. C.,
*An Introduction to the Theory of Aeroelasticity*, 1955 (Dover, 1969). - Scanlan, R. H. and Rosenbaum,
*Introduction to the Study of Aircraft Vibration*and Flutter, The Macmillian Co., 1951. - Dowell, E. H.,
*Aeroelasticity of Plates and Shells*, Noordhoff International Publishing, 1975. *AGARD Manual on Aeroelasticity in Axial-Flow Turbomachines, Vol. 2, Structural Dynamics and Aeroelasticity*, Platzer, M. F. and Carta, F. O., editors, AGARD-AG-298, 1988.- Johnson, W.,
*Helicopter Theory*, Dover, 1980. - Bielawa, R. L.,
*Rotary Wing Structural Dynamics and Aeroelasticity*, AIAA Education Series, 1992. - Atluri, S. N. (editor), Computational Nonlinear Mechanics in Aerospace Engineering, Progress in Astronautics and Aeronautics, Vol. 146, 1992. (TL790.P964 v.146)
- Bolotin, V. V.,
*Dynamic Stability of Elastic Systems*, Holden-Day, 1964. (QA931.B693 c.6) - Craig, R. R.,
*Structural Dynamics: An Introduction to Computer Methods*, Wiley, 1981. (TA654.C72) - Meirovitch, L.,
*Elements of Vibration Analysis*, McGraw-Hill, 1986. (QA935.M53) - Meirovitch, L.,
*Analytical Methods in Vibrations*, MacMillan, 1967. - Washizu, K.,
*Variational Methods in Elasticity and Plasticity*, Pergamon, 2nd ed., 1974. (QA931.W319)
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Problem Sets | |