Application of Finite Element Modeling (FEM) to Oral Targeted Delivery of Therapeutics A paper from the State-of-the-Art in Application of Finite Element Numerical Solutions to Engineering Problems: A Session Honoring Pioneering Contributions of Professor

2009 ◽  
Author(s):  
Nahor Haddish-Berhane ◽  
Kamyar Haghighi
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Targeted Delivery ◽  
Numerical Solutions ◽  
State Of The Art ◽  
The State ◽  
Element Modeling ◽  
Engineering Problems

scholarly journals The Geometric Role of Precisely Engineered Imperfections on the Critical Buckling Load of Spherical Elastic Shells

2016 ◽  
Vol 83 (11) ◽  
Author(s):  
Anna Lee ◽  
Francisco López Jiménez ◽  
Joel Marthelot ◽  
John W. Hutchinson ◽  
Pedro M. Reis
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Shell Theory ◽  
Numerical Solutions ◽  
Buckling Load ◽  
Quantitative Relation ◽  
Angular Width ◽  
Elastic Shells ◽  
Critical Buckling Load ◽  
Element Modeling

We study the effect of a dimplelike geometric imperfection on the critical buckling load of spherical elastic shells under pressure loading. This investigation combines precision experiments, finite element modeling, and numerical solutions of a reduced shell theory, all of which are found to be in excellent quantitative agreement. In the experiments, the geometry and magnitude of the defect can be designed and precisely fabricated through a customizable rapid prototyping technique. Our primary focus is on predictively describing the imperfection sensitivity of the shell to provide a quantitative relation between its knockdown factor and the amplitude of the defect. In addition, we find that the buckling pressure becomes independent of the amplitude of the defect beyond a critical value. The level and onset of this plateau are quantified systematically and found to be affected by a single geometric parameter that depends on both the radius-to-thickness ratio of the shell and the angular width of the defect. To the best of our knowledge, this is the first time that experimental results on the knockdown factors of imperfect spherical shells have been accurately predicted, through both finite element modeling and shell theory solutions.

Sign in / Sign up

Export Citation Format

Share Document