Simulation of flow transients in liquid pipeline systems

Zeren, Zekai Uygur
The most basic property of a muscle is its ability to contract and produce force when stimulated. A muscle is mainly composed of cells consisting of myofibrils with its basic unit called as a sarcomere. A sarcomere is composed of actin and myosin responsible for the muscle contraction. The Hill-type muscle model is the most commonly used model to simulate the behavior of a muscle. A muscle can produce its maximum force at isometric conditions. The level of force produced in the muscle is determined by the the frequency of the signals from the CNS. The force production is also a function of force-muscle current velocity and force-muscle current length relations. A muscle contains two types of sensors; i.e. muscle spindle and golgi tendon organ, which give rise to the feedback control of the muscle length and muscle contraction velocity. In this study a 1-D model of a muscle is formed step by step in Simulink. In the models the muscle mechanics has been investigated and the results are compared with the previous works.


Modeling and simulation of viscous electro-active polymers
Vogel, Franziska; Göktepe, Serdar; Steinmann, Paul; Kuhl, Ellen (2014-11-01)
Electro-active materials are capable of undergoing large deformation when stimulated by an electric field. They can be divided into electronic and ionic electro-active polymers (EAPs) depending on their actuation mechanism based on their composition. We consider electronic EAPs, for which attractive Coulomb forces or local re-orientation of polar groups cause a bulk deformation. Many of these materials exhibit pronounced visco-elastic behavior. Here we show the development and implementation (o)f a constitu...
Assessment of hand-type hammer drill bits under percussive loading
Demir, Osman Koray; Çalışkan, Mehmet; Department of Mechanical Engineering (2007)
The task of a drill bit in percussive drilling is to transport the initial kinetic energy of the hammer to the workpiece in terms of stress waves. The efficiency of this transportation and the stresses that the drill bit is exposed to during the process is dependent on the nature of the stress waves. In hand-type hammer drilling, changing dimensions of the bit means changing conditions for the propagation and interaction of the stress waves. In this study, using finite element method, wave propagation and i...
Propagation of waves from a spherical cavity with and without a shell embedment
Akkas, N; Zakout, U; Tupholme, GE (Springer Science and Business Media LLC, 2000-01-01)
A spherical cavity in an infinite, elastic medium with and without a shell embedment is subjected to axisymmetric, non-torsional surface loads in the radial and meridional directions. The so-called Residual Variable Method (RVM) is used to obtain exact, closed-form solutions of the wave propagation problems. Some representative numerical results are presented graphically for the stresses created in two realistic loading situations.
Modeling and control of constrained flexible joint parallel manipulators
Oğan, Osman Can; İder, Kemal; Department of Mechanical Engineering (2010)
The purpose of the thesis is to achieve a hybrid force and motion control method of parallel manipulators working in a constrained environment, in the presence of joint flexibility that occurs at the actuated joints. A flexible joint is modeled and the equations of motion of the parallel manipulator are derived by using the Lagrange formulation. The structural damping of the active joints, viscous friction at the passive joints and the rotor damping are also considered in the model. It is shown that in a fl...
Arıkan, Mehmet Ali Sahir (1994-01-01)
Contact stresses in bodies in line contact are determined by using the analytical expressions developed for two elastic bodies held in contact by forces normal to the area of contact and accompanied by frictional (tangential) forces. Variations of the stresses in the contact region, and effect of coefficient of friction on these stresses is investigated. Maximum values of principal, maximum shearing and von Mises stresses are determined for static failure analysis; mean and alternating von Mises stresses ...
Citation Formats
Z. U. Zeren, “Simulation of flow transients in liquid pipeline systems,” M.S. - Master of Science, Middle East Technical University, 2007.