lecture-iv fem applications in dynamics
DESCRIPTION
Lecture-IV FEM Applications in DynamicsTRANSCRIPT
BITS Pilani Hyderabad Campus
CE G551 Dynamics of Structures Instructor: Mr. J S Kalyana Rama
Course Lecture-IV
Application of FEM to Structural Dynamics
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Contents
Dynamic analysis of Water Tanks
Dynamic analysis of Bridges
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Dynamic analysis of Water Tanks
Elephant-foot buckling of a tank wall (courtesy
of University of California at Berkeley)
Sloshing damage to upper shell of tank (courtesy of University of
California at Berkeley)
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Liquid-filled tank modelled by generalized single-degree-of-
freedom systems
Method of Dynamic Analysis
• The dynamic analysis of a liquid-filled
tank may be carried out using the
concept of generalized single-degree-of
freedom (SDOF) systems representing
the impulsive and convective modes of
vibration of the tank-liquid system.
• For practical applications, only the first
few modes of vibration need to be
considered in the analysis.
• For a given earthquake ground motion,
the response of various SDOF systems
may be calculated independently and
then combined to give the net base
shear and overturning moment.
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Solid model of experimental set-up
Water Sloshing in Rectangular Tanks – An Experimental Investigation &
Numerical Simulation: Mechanical Engineering, Petroleum Institute, P.O. Box
2533 Abu Dhabi, UAE
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Actual experimental set-up
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Schematic of the experimental setup
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Image Processing
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Comparison between experimental and numerical results for 50% fill level and 4.5 kg
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Comparison between experimental and numerical results for 50% fill level and 4.5 kg
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
A STUDY ON SLOSHING FREQUENCIES OF FLUID-TANK SYSTEM
Visvesvaraya National Institute of Technology, Nagpur, India
Where, fc = Sloshing frequency (Hz), h = height of water in tank (m), L = length of rectangular tank along direction of excitation
(m), D= diameter of circular tank (m), g = acceleration due to gravity (m/s2)
For the circular and rectangular tanks, the first sloshing frequency is given by Housner, 1963): as
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
Details of tanks of other shapes
Circular tank of 170
mm diameter and
230 mm
height (Model 1);
square tank of plan
size 270mm x
270mm and 300
mm height (Model
2); rectangular tank
of plan size 270
mm x 135 mm and
300 mm height
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
First sloshing mode of liquid in tanks of different shapes
BITS Pilani, Hyderabad Campus Instructor: Mr. J S Kalyana Rama
• Clough and Penzein
• A K Chopra
• Slides from Different foreign Universities
• Wikipedia.org
• Technical University of Denmark-Material for Dynamics
References
BITS Pilani Hyderabad Campus
THANK YOU!