A new formulation of the immersed boundary method with a structure algebraically identical to the traditional fractional step method is presented for incompressible flow over bodies with prescribed surface motion. Like previous methods, a boundary force is applied at the immersed surface to satisfy the no-slip constraint. This extra constraint can be added to the incompressible Navier–Stokes eq...

We study the equilibrium states for an energy functional with a parametric force field on a region of a surface. Consideration of free equilibrium states is based on Lyusternik - Schnirelman's and Skrypnik's variational methods. Consideration of equilibrium states under a constraint of geometrical character is based on an analog of Skrypnik's method, described in [P. Vyridis, {it Bifurcation in...

where λ is the Lagrange multiplier and ψ = 0 the holonomic constraint. The first practical algorithm for constrained dynamics was called SHAKE [3]. In this algorithm the Lagrange multiplier was calculated from the viewpoint, that no exact discrete solution could be obtained. Thus the constraints were satisfied by inserting the discrete propagator into the holonomic constraint, ψ(t+ h) = 0. This...

This paper studies the generalized version of theZakharov-Kuznetsov Benjamin-Bona-Mahoney equation. The functionalvariable method as well as the simplest equation method areapplied to obtain solitons and singular periodic solutions to theequation. There are several constraint conditions that arenaturally revealed in order for these specialized type ofsolutions to exist. The results of this pape...

In this paper, the coupled dispersive (2+1)-dimensional long wave equation is studied. The traveling wave hypothesis yields complexiton solutions. Subsequently, the wave equation is studied with power law nonlinearity where the ansatz method is applied to yield solitary wave solutions. The constraint conditions for the existence of solitons naturally fall out of the derivation of the soliton so...

Dynamic control of constrained mechanical systems, such as robotic manipulators under end-effector constraints, parallel manipulators, and multifingered robotic hands under closure constraints have been classic problems in robotics research. There have been numerous treatments on modeling, analysis, and control for each class of problem. In this paper, we provide a unified geometric framework f...

in the current study the effect of casimir force and squeezed film damping on the pull-in instability and dynamic behavior of electrostatically actuated nano and micro electromechanical systems is investigated separately. linear elastic membrane theory is used to model the static and dynamic behavior of system for strip, annular and disk geometries. squeezed film damping effect is modeled using...

The purpose of this study is to derive optimal shapes of a body located in viscous flows by the finite element method using the acoustic velocity and the four-step explicit scheme. The formulation is based on an optimal control theory in which a performance function of the fluid force is introduced. The performance function should be minimized satisfying the state equation. This problem can be ...