Flows with moving boundaries and interfaces (MBI) are a large class of problems that include fluid-particle and fluid-structure interactions, and in broader terms, moving solid surfaces. They also include multi-fluid ...
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Flows with moving boundaries and interfaces (MBI) are a large class of problems that include fluid-particle and fluid-structure interactions, and in broader terms, moving solid surfaces. They also include multi-fluid flows, and as a special case of that, free-surface flows, sometimes in combination with moving solid surfaces. In some classes of MBI problems the solid surfaces could be in fast, linear or rotational relative motion or could come into contact. In almost all real-world applications, the solid surfaces would have complex geometries. All these problems are frequently encountered in engineering analysis and design, pose some of the most formidable computational challenges, and have a common core computational technology need. Bringing solution and analysis to them motivated the development of a good number of core computational methods and special methods targeting specific classes of MBI problems. This paper is an overview of some of those core and special methods. The focus is on isogeometric analysis, complex geometries, incompressible-flow Space-Time Variational Multiscale (ST-VMS) and Arbitrary Lagrangian-Eulerian VMS (ALE-VMS) methods, compressible-flow ST Streamline-Upwind/Petrov-Galerkin (ST-SUPG) and ALE-SUPG methods, and some of the special methods developed in connection with these core ST and ALE methods. The incompressible-flow ST-VMS and ALE-VMS and compressible-flow ST-SUPG and ALE-SUPG are moving-mesh methods, where the mesh moves to have mesh-resolution control near the fluid-solid interfaces, enabling high-resolution boundary-layer representation, an essential feature when the accuracy in representing the boundary layer is a priority. The computational examples presented are car and tire aerodynamics with road contact and tire deformation, ventricle-valve-aorta flow, and gas turbine flow.
Understanding the dynamics of phase boundaries in fluids requires quantitative knowledge about the microscale processes at the *** consider the sharp-interface motion of the compressible two-component flow and propose...
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Understanding the dynamics of phase boundaries in fluids requires quantitative knowledge about the microscale processes at the *** consider the sharp-interface motion of the compressible two-component flow and propose a heterogeneous multiscale method(HMM)to describe the flow fields *** multiscale approach combines a hyperbolic system of balance laws on the continuum scale with molecular-dynamics(MD)simulations on the microscale ***,the multiscale approach is necessary to compute the interface dynamics because there is—at present—no closed continuum-scale *** basic HMM relies on a moving-mesh finite-volume method and has been introduced recently for the compressible one-component flow with phase transitions by Magiera and Rohde in(J Comput Phys 469:111551,2022).To overcome the numerical complexity of the MD microscale model,a deep neural network is employed as an efficient surrogate *** entire approach is finally applied to simulate droplet dynamics for argon-methane mixtures in several space *** our knowledge,such compressible two-phase dynamics accounting for microscale phase-change transfer rates have not yet been computed.
We develop a one-dimensional moving-mesh method for hyperbolic systems of conservation laws. This method is based on the high-resolution finite-volume "wave-propagation method", implemented in the CLAWPACK s...
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We develop a one-dimensional moving-mesh method for hyperbolic systems of conservation laws. This method is based on the high-resolution finite-volume "wave-propagation method", implemented in the CLAWPACK software package. A modified system of conservation laws is solved on a fixed, uniform computational grid, with a grid mapping function computed simultaneously in such a way that in physical space certain features are tracked by cell interfaces. The method is tested on a shock-tube problem with multiple reflections where the contact discontinuity is tracked, and also on two multifluid problems where the interface between two distinct gases is tracked. One is a standard test problem and the other also involves a moving piston whose motion is also tracked by the movingmesh. (C) 2003 Elsevier Science Ltd. All rights reserved.
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