General tube law for collapsible thin and thick-wall tubes.
Modeling the complex deformations of cylindrical tubes under external pressure is of interest in engineering and physiological applications. The highly non-linear post-buckling behavior of cross-section of the tube during collapse attracted researchers for years. Major efforts were concentrated on studying the behavior of thin-wall tubes. Unfortunately, the knowledge on post-buckling of thick-wall tubes is still incomplete, although many experimental and several theoretical studies have been performed. In this study we systematically studied the effect of the wall thickness on post-buckling behavior of the tube. For this purpose, we utilized a computational model for evaluation of the real geometry of the deformed cross-sectional area due to negative transmural (internal minus external) pressure. We also developed an experimental method to validate the computational results. Based on the computed cross-sections of tubes with different wall thicknesses, we developed a general tube law that accounts for thin or thick wall tubes and fits the numerical data of computed cross-sectional areas versus transmural pressures.
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, 69978, Israel.
Pavel
P
Kozlovsky
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, 69978, Israel.
Uri
U
Zaretsky
Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky, Medical Center, Tel Aviv 64239 and Sackler Faculty of Medicine, TelAviv University, Tel Aviv 69978, Israel.
Ariel J
AJ
Jaffa
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, 69978, Israel. Electronic address: elad@post.tau.ac.il.
David
D
Elad
D001698:Biomedical Engineering / Q000379:methods*; D003198:Computer Simulation; D004867:Equipment Design; D007091:Image Processing, Computer-Assisted; D008962:Models, Theoretical; D009068:Movement; D011312:Pressure; D012212:Rheology; D014463:Ultrasonography
Active contours; Collapsible elastic tubes; Thick-wall tubes; Tube-law; Ultrasound imaging