With the intermediate flow states predicted by local two phase Riemann problem,the modified ghost fluid method(MGFM)and its variant(r GFM)have been widely employed to resolve the interface condition in the simulation ...With the intermediate flow states predicted by local two phase Riemann problem,the modified ghost fluid method(MGFM)and its variant(r GFM)have been widely employed to resolve the interface condition in the simulation of compressible multi-medium flows.In this work,the drawback of the construction procedure of local two phase Riemann problem in r GFM was investigated in detail,and a refined version of the construction procedure was specially developed to make the simulation of underwater explosion bubbles more accurate and robust.Beside the refined r GFM,the fast and accurate particle level set method was also adopted to achieve a more effective and computationally efficient capture of the evolving multi-medium interfaces during the simulation.To demonstrate the improvement brought by current refinement,several typical numerical examples of underwater explosion bubbles were performed with original r GFM and refined r GFM,respectively.The results indicate that,when compared with original r GFM,numerical oscillations were effectively removed with the proposed refinement.Accordingly,with present refined treatment of interface condition,a more accurate and robust simulation of underwater explosion bubbles was accomplished in this work.展开更多
In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high mag...In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high magnitude(such that the solid medium can be under plastic compression)to a subsequently very low quantity(so that cavitation can occur in the fluid).New techniques are also developed in the definition of the ghost fluid status when the structure is under plastic deformation or when the flow is under cavitation next to the structure.Numerical results show that the improved MGFM for treatment of the fluid-deformable structure coupling works efficiently for all pressure ranges and is capable of simulating cavitation evolution and cavitation re-loading in conjunction with the employment of the isentropic one-fluid cavitation model.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.041322062 and 51075004)the Foundation of Zhejiang Educational Committee(Grant No.529003+G21144)
文摘With the intermediate flow states predicted by local two phase Riemann problem,the modified ghost fluid method(MGFM)and its variant(r GFM)have been widely employed to resolve the interface condition in the simulation of compressible multi-medium flows.In this work,the drawback of the construction procedure of local two phase Riemann problem in r GFM was investigated in detail,and a refined version of the construction procedure was specially developed to make the simulation of underwater explosion bubbles more accurate and robust.Beside the refined r GFM,the fast and accurate particle level set method was also adopted to achieve a more effective and computationally efficient capture of the evolving multi-medium interfaces during the simulation.To demonstrate the improvement brought by current refinement,several typical numerical examples of underwater explosion bubbles were performed with original r GFM and refined r GFM,respectively.The results indicate that,when compared with original r GFM,numerical oscillations were effectively removed with the proposed refinement.Accordingly,with present refined treatment of interface condition,a more accurate and robust simulation of underwater explosion bubbles was accomplished in this work.
文摘In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high magnitude(such that the solid medium can be under plastic compression)to a subsequently very low quantity(so that cavitation can occur in the fluid).New techniques are also developed in the definition of the ghost fluid status when the structure is under plastic deformation or when the flow is under cavitation next to the structure.Numerical results show that the improved MGFM for treatment of the fluid-deformable structure coupling works efficiently for all pressure ranges and is capable of simulating cavitation evolution and cavitation re-loading in conjunction with the employment of the isentropic one-fluid cavitation model.
