|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | AnAdaptive Moving Mesh Method for Two-Dimensional Incompressible Viscous Flows显示文摘In this paper, we present an adaptive moving mesh technique for solvingthe incompressible viscous flows using the vorticity stream-function formulation. Themoving mesh strategy is based on the approach proposed by Li et al. [J. Comput. Phys.,170 (2001), pp. 562–588] to separate the mesh-moving and evolving PDE at each timestep. The Navier-Stokes equations are solved in the vorticity stream-function form bya finite-volume method in space, and the mesh-moving part is realized by solving theEuler-Lagrange equations to minimize a certain variation in conjunction with a moresophisticated monitor function. A conservative interpolation is used to redistributethe numerical solutions on the new meshes. This paper discusses the implementationof the periodic boundary conditions, where the physical domain is allowed to deformwith time while the computational domain remains fixed and regular throughout. Numericalresults demonstrate the accuracy and effectiveness of the proposed algorithm. | Zhijun Tan K.M.Lim B.C.Khoo | 2008 | Communications in Computational Physics2008，3，3： | 1 |
| 2 | Shear stress-induced pH increase in plasma is mediated by a decrease in P(CO,(2):the increase in pH enhances shear stress-nduced P-selectin expression in platelets显示文摘 | Chung K.Y K.M.Lim Chung S.M | | 0，，03： | 1 |
| 3 | A BEM/FEM Coupling Approach for Fluid-Structure Interaction Simulation of Cell Motion显示文摘In this paper, accurate and efficient simulation of cell motion in a biological fluid flow is investigated. The membrane of a moving cell is represented by athin shell composed of incompressible neo-Hookean elastic materials and the liquidsaround the membrane are approximated as incompressible Newtonian flows with lowReynolds numbers. The biofluid mechanics is approximated by the Stokes flow equations. A low-order BEM model is developed for the two biological fluids coupled atthe membrane surface. The moving boundary problem in fluid mechanics can be effectively solved using the BEM with a GMRES solver. The FEM model based on a flatthin shell element is further developed to predict the membrane load due to the largedeformation of a moving cell. Computational efficiency is greatly improved due tothe one-dimensional reduction in the present BEM and FEM models. The BEM solverfor the biological fluids is coupled with the FEM solver for the cell membrane at themembrane surface. The position of the membrane surface nodes is advanced in time byusing the classical fourth-order Runge-Kutta method. Numerical instability is avoidedby using a relatively small time step. Further numerical instabilities in the FEM solveris alleviated by using various techniques. The present method is applied to the FSIproblems of cell motion in a cylindrical flow. Numerical examples can illustrate thedistinct accuracy, efficiency and robustness of the present method. Furthermore, theimportance of bending stiffness of a cell membrane for stable cell motion simulation isemphasized. It is suggested that the present approach be an appealing alternative forsimulating the fluid-structure interaction of moving cells. | S.Y.Wang P.Q.Chen K.M.Lim B.C.Khoo | 2010 | Communications in Computational Physics2010，7，5： | 0 |
| 4 | An Implementation ofMAC Grid-Based IIM-Stokes Solver for Incompressible Two-Phase Flows显示文摘Abstract.In this paper,a novel implementation of immersed interface method combined with Stokes solver on a MAC staggered grid for solving the steady two-fluid Stokes equations with interfaces.The velocity components along the interface are introduced as two augmented variables and the resulting augmented equation is then solved by the GMRES method.The augmented variables and/or the forces are related to the jumps in pressure and the jumps in the derivatives of both pressure and velocity,and are interpolated using cubic splines and are then applied to the fluid through the jump conditions.The Stokes equations are discretized on a staggered Cartesian grid via a second order finite difference method and solved by the conjugate gradient Uzawa-typemethod.The numerical results show that the overall scheme is second order accurate.The major advantages of the present IIM-Stokes solver are the efficiency and flexibility in terms of types of fluid flow and different boundary conditions.The proposed method avoids solution of the pressure Poisson equation,and comparisons are made to show the advantages of time savings by the present method.The generalized two-phase Stokes solver with correction terms has also been applied to incompressible two-phase Navier-Stokes flow. | Zhijun Tan K.M.Lim B.C.Khoo | 2011 | Communications in Computational Physics2011，10，10： | 0 |
| 5 | An Indirect-Forcing Immersed Boundary Method for Incompressible Viscous Flows with Interfaces on Irregular Domains显示文摘An indirect-forcing immersed boundary method for solving the incompressible Navier-Stokes equations involving the interfaces and irregular domains is developed.The rigid boundaries and interfaces are represented by a number of Lagrangian control points.Stationary rigid boundaries are embedded in the Cartesian grid and singular forces at the rigid boundaries are applied to impose the prescribed velocity conditions.The singular forces at the interfaces and the rigid boundaries are then distributed to the nearby Cartesian grid points using the immersed boundary method.In the present work,the singular forces at the rigid boundaries are computed implicitly by solving a small system of equations at each time step to ensure that the prescribed velocity condition at the rigid boundary is satisfied exactly.For deformable interfaces,the forces that the interface exerts on the fluid are computed from the configuration of the elastic interface and are applied to the fluid.The Navier-Stokes equations are discretized using finite difference method on a staggered uniform Cartesian grid by a second order accurate projection method.The ability of the method to simulate viscous flows with interfaces on irregular domains is demonstrated by applying to the rotational flow problem,the relaxation of an elastic membrane and flow in a constriction with an immersed elastic membrane. | Zhijun Tan K.M.Lim B.C.Khoo Desheng Wang | 2009 | Communications in Computational Physics2009，6，10： | 0 |
| 6 | An Immersed Interface Method for the Simulation of Inextensible Interfaces in Viscous Fluids显示文摘In this paper,an immersed interface method is presented to simulate the dynamics of inextensible interfaces in an incompressible flow.The tension is introduced as an augmented variable to satisfy the constraint of interface inextensibility,and the resulting augmented system is solved by the GMRES method.In this work,the arclength of the interface is locally and globally conserved as the enclosed region undergoes deformation.The forces at the interface are calculated from the configuration of the interface and the computed augmented variable,and then applied to the fluid through the related jump conditions.The governing equations are discretized on a MAC grid via a second-order finite difference scheme which incorporates jump contributions and solved by the conjugate gradient Uzawa-type method.The proposed method is applied to several examples including the deformation of a liquid capsule with inextensible interfaces in a shear flow.Numerical results reveal that both the area enclosed by interface and arclength of interface are conserved well simultaneously.These provide further evidence on the capability of the present method to simulate incompressible flows involving inextensible interfaces. | Zhijun Tan D.V.Le K.M.Lim B.C.Khoo | 2012 | Communications in Computational Physics2012，11，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员