This paper presents a comparative study of a meshless level-set method in the simulation of sloshing flows. The numerical moving particle semi-implicit (MPS) method and a grid based schemes of the MPS and level-set ...This paper presents a comparative study of a meshless level-set method in the simulation of sloshing flows. The numerical moving particle semi-implicit (MPS) method and a grid based schemes of the MPS and level-set methods are outlined and two violent sloshing cases are considered. The computed results are compared with the corresponding experimental data for validation. The impact pressure and the deformations of free surface induced by sloshing are comparatively analyzed, and are in good agreement with experimental ones. Results show that both the MPS and level-set methods are good tools for simulation of violent sloshing flows. However, the second pressure peaks as well as breaking and splashing of free surface by the MPS method are captured better than by the level-set method.展开更多
Generating body-fitted particle distribution for arbitrarily complex geometry underpins the applications of particle-based method to engineering and bioengineering and is highly challenging,and thus hinders the potent...Generating body-fitted particle distribution for arbitrarily complex geometry underpins the applications of particle-based method to engineering and bioengineering and is highly challenging,and thus hinders the potential of particle methods.In this paper,we present a new computer-aided design(CAD)compatible body-fitted particle generator,termed as CAD-BPG,for arbitrarily complex 3-D geometry.By parsing a CAD model,the present method can accurately tackle arbitrarily complex geometry representation and describe the corresponding geometry surface by constructing an implicit zero level-set function on Cartesian background mesh.To achieve a body-fitted and isotropic particle distribution,physics-driven relaxation process with surface bounding governed by the transport-velocity formulation of smoothed particle hydrodynamics(SPH)methodology is conducted to characterize the particle evolution.A set of examples,ranging from propeller,stent structures and anatomical heart models,show simplicity,accuracy and versatility of the present CAD-BPG for generating body-fitted particle distribution of arbitrarily complex 3-D geometry.Last but not least,the present CAD-BPG is applied for modeling wave-structure interaction,where wave interaction with an oscillating wave surge converter is studied,and the results show that the present method not only provides an efficient and easy-to-implement pre-processing tool for particle-based simulation but also improves the numerical accuracy compared with lattice particle distribution.Consequently,the propose CAD-BPG sheds light on simulating real-world applications by particle-based methods for researchers and engineers.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51379125,51411130131 and 11272120)the National Key Basic Research Development of China(973 Program,Grant No.2013CB036103)+1 种基金the High Te-chnology of Marine Research Project of the Ministry of Indu-stry and the Information Technology of Chinathe Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(Grant No.2013022)
文摘This paper presents a comparative study of a meshless level-set method in the simulation of sloshing flows. The numerical moving particle semi-implicit (MPS) method and a grid based schemes of the MPS and level-set methods are outlined and two violent sloshing cases are considered. The computed results are compared with the corresponding experimental data for validation. The impact pressure and the deformations of free surface induced by sloshing are comparatively analyzed, and are in good agreement with experimental ones. Results show that both the MPS and level-set methods are good tools for simulation of violent sloshing flows. However, the second pressure peaks as well as breaking and splashing of free surface by the MPS method are captured better than by the level-set method.
基金the National Natural Science Foundation of China(Grant No.91952110)the Deutsche Forschungsgemeinschaft under(Grant Nos.DFG HU 1572/10-1,DFG HU1527/12-1).
文摘Generating body-fitted particle distribution for arbitrarily complex geometry underpins the applications of particle-based method to engineering and bioengineering and is highly challenging,and thus hinders the potential of particle methods.In this paper,we present a new computer-aided design(CAD)compatible body-fitted particle generator,termed as CAD-BPG,for arbitrarily complex 3-D geometry.By parsing a CAD model,the present method can accurately tackle arbitrarily complex geometry representation and describe the corresponding geometry surface by constructing an implicit zero level-set function on Cartesian background mesh.To achieve a body-fitted and isotropic particle distribution,physics-driven relaxation process with surface bounding governed by the transport-velocity formulation of smoothed particle hydrodynamics(SPH)methodology is conducted to characterize the particle evolution.A set of examples,ranging from propeller,stent structures and anatomical heart models,show simplicity,accuracy and versatility of the present CAD-BPG for generating body-fitted particle distribution of arbitrarily complex 3-D geometry.Last but not least,the present CAD-BPG is applied for modeling wave-structure interaction,where wave interaction with an oscillating wave surge converter is studied,and the results show that the present method not only provides an efficient and easy-to-implement pre-processing tool for particle-based simulation but also improves the numerical accuracy compared with lattice particle distribution.Consequently,the propose CAD-BPG sheds light on simulating real-world applications by particle-based methods for researchers and engineers.