2020 Faculty Courses School of Engineering Department of Mechanical Engineering Graduate major in Mechanical Engineering
Rotor Dynamics
- Academic unit or major
- Graduate major in Mechanical Engineering
- Instructor(s)
- Hiroki Takahara
- Class Format
- Lecture (Zoom)
- Media-enhanced courses
- -
- Day of week/Period
(Classrooms) - 1-2 Wed (S621)
- Class
- -
- Course Code
- MEC.D432
- Number of credits
- 100
- Course offered
- 2020
- Offered quarter
- 2Q
- Syllabus updated
- Jul 10, 2025
- Language
- English
Syllabus
Course overview and goals
This course focuses on the whirling vibration of a rigid rotor. Topics include the equations of motion of a rigid rotor in the absolute and rotating coordinate systems, the comparison of two solutions corresponding to these equations of motion, unstable vibration in the case with some damping, critical speed of revolution in the case that the gyro effect is considered, and the whirling vibration of a non-isotropic rotor.
In this course, based on a clear understanding of the relation between the solutions of equations of motion and the actual whirling vibration, students will be able to recognize the relations between the solutions of equations of motion and the actual motion not only for the whirling vibration of a rigid rotor but also for other phenomena.
Course description and aims
At end of this course, students will be able to:
1) Derive the equations of motion of a rigid rotor in the absolute and rotating coordinate systems.
2) Explain the critical speed of revolution and the self-balancing effect.
3) Explain the external damping, and internal damping and their effects.
4) Explain the change of a critical speed in the case that the gyro effect is considered.
5) Explain the characteristics of the whirling vibration of a non-isotropic rotor.
Keywords
Rotor dynamics, whirling vibration, critical speed, external damping, internal damping, gyro effects, 2nd critical speed,
Competencies
- Specialist skills
- Intercultural skills
- Communication skills
- Critical thinking skills
- Practical and/or problem-solving skills
Class flow
At the beginning of each class, the previous class will be briefly reviewed.
Course schedule/Objectives
| Course schedule | Objectives | |
|---|---|---|
| Class 1 | Introduction of rotor dynamics | Review of vibration characteristics of single degree of freedom system |
| Class 2 | Equations of motion of a rigid rotor in a stationary and rotating coordinate systems and a whirling vibration | Understanding of whirling vibration, critical speed, self-balancing, free vibration and degeneration |
| Class 3 | Vibration of a rigid rotor in the case with some damping, balancing of rotor | Understanding of effects of an external and internal damping, static balancing and |
| Class 4 | Whirling vibration in the case with support with non-isotropic stiffness | Understanding of forward whirling and backward whirling |
| Class 5 | Equations of motion in case in the case that a gyro effect is considered | Derivation of equations of motion in case in the case that a gyro effect is considered |
| Class 6 | Equations of motion in case in the case that a gyro effect is considered | Understanding of relation between the rotational speed and critical speed |
| Class 7 | Whirling vibration of a non-isotropic rotor, 2nd critical speed and Confirmation of achievement level of lecture | Understanding of unstable vibration of non-isotropic rotor and 2nd critical speed |
Study advice (preparation and review)
To enhance effective learning, students are encouraged to spend approximately 100 minutes preparing for class and another 100 minutes reviewing class content afterwards (including assignments) for each class.
They should do so by referring to textbooks and other course material.
Textbook(s)
None required.
Reference books, course materials, etc.
Handouts will be distributed at beginning of class when necessary.
Evaluation methods and criteria
1.Students will be assessed on their understanding of critical speed, forward whirling, backward whirling, and so on.
2. The student’s course score is based on exercise problems
Related courses
- MEC.D201 ： Mechanical Vibrations
- MEC.D311 ： Vibration Analysis
Prerequisites
Students must have successfully completed Mechanical Vibrations(MEC.D201.R) or have equivalent knowledge.