Vibration of Periodic Structures

Vibration of Periodic Structures Course
  • This new practical course, taught by a key contributor/leading technical authority on the subject, is applicable to the study of vibration, flutter, and structural-acoustic analysis of stiffened structures, used in Aerospace, Civil and Mechanical Engineering.
  • All students will receive an AIAA Certificate of Completion at the end of the course.

OVERVIEW
Many engineering structures, e.g., fuselage of an aircraft, tall buildings, long bridges are periodic, consisting of repetition of a basic periodic unit. Modelling such structures based on the conventional finite element method can be time consuming and expensive. However, the task can be accomplished in a cost-effective manner, by taking the periodicity of the structure into account. The basic concepts will be explained by analyzing periodic spring-mass systems, periodically stiffened beams and plates and periodically stiffened models of an airplane fuselage section. Examples will include prediction of natural frequencies, structural response, sound transmission, and supersonic panel flutter.

AUDIENCE: Aerospace, Civil and Mechanical Engineers involved in design and analysis of stiffened structures, subjected to dynamic excitations e.g., jet noise and boundary layer turbulence excitations, supersonic or hypersonic flow. Professors and graduate students involved in research on structural dynamics, acoustics and aeroelasticity.


COURSE INFORMATION
Type of Course: Instructor-Led Short Course
Course Level: Fundamentals
Course Length: 3 days
AIAA CEU's available: Yes

Outline
LEARNING OBJECTIVES / OUTLINE 
  • Learn about the fundamentals of the Periodic structure theory. 
  • Learn how to predict the natural frequencies of periodically stiffened beams and plates. 
  • Learn how to predict the response and sound transmission through a periodically stiffened structure subjected to a convected pressure field. 
  • Learn how to combine the Finite Element Method (FEM) with the Periodic Structure (PS) theory for prediction of the structural-acoustic natural frequencies and response of an aircraft fuselage section in a cost-effective manner, compared to application of traditional FEM. 
  • Learn about Intrinsic Structural Tuning to reduce the structural-acoustic response of a periodically stiffened structure. 
  • Learn about the effects of deviations from periodicity. 
  • Learn how to predict the flutter characteristics of a periodic structure exposed to supersonic flow. 
  • Learn about examples of many other applications, e.g., vibration of circular rings on periodic support, wave propagation in a periodically supported pipe carrying fluid, vibration of heat exchanger tube banks of nuclear reactors, application to composite materials, dynamics of rotationally periodic structures, vibration control of a periodic railroad track, improving flutter characteristics of an airplane wing., etc.
Materials
Recommended Textbook: Vibration of Periodic Structures, Author: Gautam SenGupta, scheduled to be Published by Elsevier in 2023. The book will be available to the attendees at a discount from the publisher.
Instructors
Dr. Gautam SenGupta received his BSc (Physics) from Presidency College, Calcutta, (India), BTech. (Mech. Eng.) from IIT, Kharagpur (India), and his PhD from the University of Southampton (UK), where he developed a unique method for predicting the natural frequencies of periodic structures. He worked as a Specialist Engineer in Acoustic Fatigue at the Royal Aeronautical Society of England, and at NASA-Langley as a Research Associate. He joined Boeing in 1973, where he applied the Periodic Structure Theory to predict and control the structural acoustic characteristics of an airplane fuselage in a cost-effective manner. He retired in 2016 as a Technical Fellow of the Boeing Company in Seattle, where he was also involved in developing methods for predicting airframe noise, and transonic flutter characteristics of airplanes. He is an Affiliate Professor at the University of Washington, where he teaches courses on Structural Dynamics and related subjects.

 

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