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D W Schwendeman - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and Incompressible Flow model problem analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An analysis is made of a new partitioned scheme for solving fluid-structure interaction problems involving viscous Incompressible Flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and Incompressible Flow part i model problem analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) problems involving viscous Incompressible Flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and analysis of some model problems. The analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
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an analysis of a new stable partitioned algorithm for fsi problems part i Incompressible Flow and elastic solids
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. Importantly, these new added-mass partitioned (AMP) schemes are stable and retain full accuracy with no sub-iterations per time step, even in the presence of strong added-mass effects (e.g. for light solids). The numerical approach described here for bulk compressible solids extends the scheme of Banks et al. [1,2] for inviscid compressible Flow, and uses Robin (mixed) boundary conditions with the fluid and solid solvers at the interface. The basic AMP Robin conditions, involving a linear combination of velocity and stress, are determined from the outgoing solid characteristic relation normal to the fluid–solid interface combined with the matching conditions on the velocity and traction. Two alternative forms of the AMP conditions are then derived depending on whether the fluid equations are advanced with a fractional-step method or not. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems; the full nonlinear case being left for future consideration. A normal mode analysis is performed to show that the new AMP algorithm is stable for any ratio of the solid and fluid densities, including the case of very light solids when added-mass effects are large. In contrast, it is shown that a traditional partitioned algorithm involving a Dirichlet–Neumann coupling for the same FSI problem is formally unconditionally unstable for any ratio of densities. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy solids.
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an analysis of a new stable partitioned algorithm for fsi problems part ii Incompressible Flow and structural shells
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. The numerical approach described here for structural shells uses Robin (mixed) interface conditions for the pressure and velocity in the fluid which are derived directly from the governing equations. The resulting added-mass partitioned (AMP) algorithm is stable even for very light structures, requires no sub-iterations per time step, and is second-order accurate. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems. A normal mode analysis is performed to show that the new AMP algorithm is stable, even for the case of very light structures when added-mass effects are large. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy structures. A summary comparison of the AMP algorithm developed here and the one in Part I is provided.
J W Banks - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and Incompressible Flow model problem analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An analysis is made of a new partitioned scheme for solving fluid-structure interaction problems involving viscous Incompressible Flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and Incompressible Flow part i model problem analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) problems involving viscous Incompressible Flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and analysis of some model problems. The analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
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an analysis of a new stable partitioned algorithm for fsi problems part i Incompressible Flow and elastic solids
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. Importantly, these new added-mass partitioned (AMP) schemes are stable and retain full accuracy with no sub-iterations per time step, even in the presence of strong added-mass effects (e.g. for light solids). The numerical approach described here for bulk compressible solids extends the scheme of Banks et al. [1,2] for inviscid compressible Flow, and uses Robin (mixed) boundary conditions with the fluid and solid solvers at the interface. The basic AMP Robin conditions, involving a linear combination of velocity and stress, are determined from the outgoing solid characteristic relation normal to the fluid–solid interface combined with the matching conditions on the velocity and traction. Two alternative forms of the AMP conditions are then derived depending on whether the fluid equations are advanced with a fractional-step method or not. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems; the full nonlinear case being left for future consideration. A normal mode analysis is performed to show that the new AMP algorithm is stable for any ratio of the solid and fluid densities, including the case of very light solids when added-mass effects are large. In contrast, it is shown that a traditional partitioned algorithm involving a Dirichlet–Neumann coupling for the same FSI problem is formally unconditionally unstable for any ratio of densities. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy solids.
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an analysis of a new stable partitioned algorithm for fsi problems part ii Incompressible Flow and structural shells
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. The numerical approach described here for structural shells uses Robin (mixed) interface conditions for the pressure and velocity in the fluid which are derived directly from the governing equations. The resulting added-mass partitioned (AMP) algorithm is stable even for very light structures, requires no sub-iterations per time step, and is second-order accurate. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems. A normal mode analysis is performed to show that the new AMP algorithm is stable, even for the case of very light structures when added-mass effects are large. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy structures. A summary comparison of the AMP algorithm developed here and the one in Part I is provided.
Yong Zhao - One of the best experts on this subject based on the ideXlab platform.
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an unstructured mesh arbitrary lagrangian eulerian unsteady Incompressible Flow solver and its application to insect flight aerodynamics
Physics of Fluids, 2016Co-Authors: Xiaohui Su, Yong ZhaoAbstract:In this paper, an unstructured mesh Arbitrary Lagrangian-Eulerian (ALE) Incompressible Flow solver is developed to investigate the aerodynamics of insect hovering flight. The proposed finite-volume ALE Navier-Stokes solver is based on the artificial compressibility method (ACM) with a high-resolution method of characteristics-based scheme on unstructured grids. The present ALE model is validated and assessed through Flow passing over an oscillating cylinder. Good agreements with experimental results and other numerical solutions are obtained, which demonstrates the accuracy and the capability of the present model. The lift generation mechanisms of 2D wing in hovering motion, including wake capture, delayed stall, rapid pitch, as well as clap and fling are then studied and illustrated using the current ALE model. Moreover, the optimized angular amplitude in symmetry model, 45°, is firstly reported in details using averaged lift and the energy power method. Besides, the lift generation of complete cyclic cl...
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an unstructured mesh arbitrary lagrangian eulerian unsteady Incompressible Flow solver and its application to insect flight aerodynamics
Physics of Fluids, 2016Co-Authors: Yuanwei Cao, Yong ZhaoAbstract:In this paper, an unstructured mesh Arbitrary Lagrangian-Eulerian (ALE) Incompressible Flow solver is developed to investigate the aerodynamics of insect hovering flight. The proposed finite-volume ALE Navier-Stokes solver is based on the artificial compressibility method (ACM) with a high-resolution method of characteristics-based scheme on unstructured grids. The present ALE model is validated and assessed through Flow passing over an oscillating cylinder. Good agreements with experimental results and other numerical solutions are obtained, which demonstrates the accuracy and the capability of the present model. The lift generation mechanisms of 2D wing in hovering motion, including wake capture, delayed stall, rapid pitch, as well as clap and fling are then studied and illustrated using the current ALE model. Moreover, the optimized angular amplitude in symmetry model, 45°, is firstly reported in details using averaged lift and the energy power method. Besides, the lift generation of complete cyclic clap and fling motion, which is simulated by few researchers using the ALE method due to large deformation, is studied and clarified for the first time. The present ALE model is found to be a useful tool to investigate lift force generation mechanism for insect wing flight.
William D Henshaw - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and Incompressible Flow model problem analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An analysis is made of a new partitioned scheme for solving fluid-structure interaction problems involving viscous Incompressible Flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and Incompressible Flow part i model problem analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) problems involving viscous Incompressible Flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and analysis of some model problems. The analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
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an analysis of a new stable partitioned algorithm for fsi problems part i Incompressible Flow and elastic solids
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. Importantly, these new added-mass partitioned (AMP) schemes are stable and retain full accuracy with no sub-iterations per time step, even in the presence of strong added-mass effects (e.g. for light solids). The numerical approach described here for bulk compressible solids extends the scheme of Banks et al. [1,2] for inviscid compressible Flow, and uses Robin (mixed) boundary conditions with the fluid and solid solvers at the interface. The basic AMP Robin conditions, involving a linear combination of velocity and stress, are determined from the outgoing solid characteristic relation normal to the fluid–solid interface combined with the matching conditions on the velocity and traction. Two alternative forms of the AMP conditions are then derived depending on whether the fluid equations are advanced with a fractional-step method or not. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems; the full nonlinear case being left for future consideration. A normal mode analysis is performed to show that the new AMP algorithm is stable for any ratio of the solid and fluid densities, including the case of very light solids when added-mass effects are large. In contrast, it is shown that a traditional partitioned algorithm involving a Dirichlet–Neumann coupling for the same FSI problem is formally unconditionally unstable for any ratio of densities. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy solids.
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an analysis of a new stable partitioned algorithm for fsi problems part ii Incompressible Flow and structural shells
Journal of Computational Physics, 2014Co-Authors: J W Banks, William D Henshaw, D W SchwendemanAbstract:Stable partitioned algorithms for fluid–structure interaction (FSI) problems are developed and analyzed in this two-part paper. Part I describes an algorithm for Incompressible Flow coupled with compressible elastic solids, while Part II discusses an algorithm for Incompressible Flow coupled with structural shells. The numerical approach described here for structural shells uses Robin (mixed) interface conditions for the pressure and velocity in the fluid which are derived directly from the governing equations. The resulting added-mass partitioned (AMP) algorithm is stable even for very light structures, requires no sub-iterations per time step, and is second-order accurate. The stability and accuracy of the AMP algorithm is evaluated for linearized FSI model problems. A normal mode analysis is performed to show that the new AMP algorithm is stable, even for the case of very light structures when added-mass effects are large. Exact traveling wave solutions are derived for the FSI model problems, and these solutions are used to verify the stability and accuracy of the corresponding numerical results obtained from the AMP algorithm for the cases of light, medium and heavy structures. A summary comparison of the AMP algorithm developed here and the one in Part I is provided.
Xiaohui Su - One of the best experts on this subject based on the ideXlab platform.
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an unstructured mesh arbitrary lagrangian eulerian unsteady Incompressible Flow solver and its application to insect flight aerodynamics
Physics of Fluids, 2016Co-Authors: Xiaohui Su, Yong ZhaoAbstract:In this paper, an unstructured mesh Arbitrary Lagrangian-Eulerian (ALE) Incompressible Flow solver is developed to investigate the aerodynamics of insect hovering flight. The proposed finite-volume ALE Navier-Stokes solver is based on the artificial compressibility method (ACM) with a high-resolution method of characteristics-based scheme on unstructured grids. The present ALE model is validated and assessed through Flow passing over an oscillating cylinder. Good agreements with experimental results and other numerical solutions are obtained, which demonstrates the accuracy and the capability of the present model. The lift generation mechanisms of 2D wing in hovering motion, including wake capture, delayed stall, rapid pitch, as well as clap and fling are then studied and illustrated using the current ALE model. Moreover, the optimized angular amplitude in symmetry model, 45°, is firstly reported in details using averaged lift and the energy power method. Besides, the lift generation of complete cyclic cl...
