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Journal of Hydrodynamics 2022年第3期34卷 408-421页

作者： Ming-Kang Li Shuai Zhang Yu-Xiang Peng A-Man Zhang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China Nanhai Institute of Harbin Engineering University Sanya572024China School of Marine Engineering and Technology Sun Yat-sen UniversityZhuhai519082China

The collapse of a cavitation bubble is an interesting topic and it has many applications in the engineering *** to its compressible nature,the modelling of a cavitation bubble is not easy by the Lagrangian method,like the smoothed particle hydrodynamics(SPH),as there is large variation of particle ***,there are two kinds of method that have been proposed to deal with this problem:the particle regeneration technique(PRT)and the volume adaptive scheme(VAS).They have all been validated via several numerical tests of compressible flow in the past *** is based on totally different concept,the ultimate simulation results and properties may ***,we intend to compare these two methods based on the Riemann-based SPH solver with monotone upwind-centered scheme for conservation laws(MUSCL)reconstruction via several numerical *** characteristics of these two methods are discussed and the applicable scope for them are also commented for further usage.

关键词： compressible flow smoothed particle hydrodynamics(SPH) particle regeneration technique(PRT) volume adaptive scheme(VAS)

Computational Analysis of the compressible flow Driven by a Piston in a Ballistic Range

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Journal of Thermal Science 2007年第4期16卷 360-369页

作者： G.Rajesh R.Mishra H.G.Kang H.D.Kim School of Mechanical Engineering Andong National University388Songcheon-DongAndong-760 749Korea

The ballistic range has long been employed in a variety of engineering fields such as high-velocity impact engineering, projectile aerodynamics and aeroballistics, since it can create an extremely high-pressure state in very short time. Since the operation of the ballistic range includes many complicated phenomena, each process should be understood in detail for the performance enhancement of the device. One of the main processes which have significant influence on the device performance is the compression process of the driver gas. Most of the studies available in this field hardly discuss this phenomenon in detail and thus lack a proper understanding of its effect on the whole system performance. In the present study, a computational analysis has been made to investigate the fluid dynamic aspects of the compression process in the pump tube of a ballistic range and to assess how it affects the performance of the ballistic range. The results obtained are validated with the available experimental data. In order to evaluate the system performance, several performance parameters are defined. Effect of a shock tube added in between the pump tube and launch tube on the performance of the ballistic range is also studied analytically. Performance of the ballistic range could be significantly improved by the proper selection of the pump tube and high-pressure tube parameters and the addition of the shock tube.

关键词： Ballistic range compressible flow piston shock tube chimera mesh

A discrete Boltzmann model with symmetric velocity discretization for compressible flow

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Chinese Physics B 2023年第11期32卷 374-382页

作者：林传栋孙笑朋苏咸利赖惠林方晓 Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Mathematics and Statistics the Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Key Laboratory of Analytical Mathematics and Applications(FJKLAMA)and Center for Applied Mathematics of Fujian Province(FJNU)Fujian Normal UniversityFuzhou 350117China

A discrete Boltzmann model(DBM) with symmetric velocity discretization is constructed for compressible systems with an adjustable specific heat ratio in the external force field. The proposed two-dimensional(2D) nine-velocity scheme has better spatial symmetry and numerical accuracy than the discretized velocity model in literature [Acta Aerodyn. Sin.40 98108(2022)] and owns higher computational efficiency than the one in literature [Phys. Rev. E 99 012142(2019)].In addition, the matrix inversion method is adopted to calculate the discrete equilibrium distribution function and force term, both of which satisfy nine independent kinetic moment relations. Moreover, the DBM could be used to study a few thermodynamic nonequilibrium effects beyond the Euler equations that are recovered from the kinetic model in the hydrodynamic limit via the Chapman–Enskog expansion. Finally, the present method is verified through typical numerical simulations, including the free-falling process, Sod’s shock tube, sound wave, compressible Rayleigh–Taylor instability,and translational motion of a 2D fluid system.

关键词： discrete Boltzmann method compressible flow nonequilibrium effect kinetic method

Numerical investigation on compressible flow around a cylinder in proximity to the heated wall

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Journal of Hydrodynamics 2024年第3期36卷 519-533页

作者： Yu-lu Liu Jun-wang Qu Yi-zhou Tao Yong-guang Lyu Xiang Qiu Shanghai Institute of Technology School of ScienceShanghai201418China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China

In this study,direct numerical simulations were conducted to investigate the compressible flow around a circular cylinder near a heated wall at a Reynolds number(Re)of 500 and a Mach number(Ma)of *** heating ratio T^(*)ranging from 1.0 to 1.6 represents the different situations of a heated wall,whereas the gap ratio ranges from 0.3 to *** study analyzed the impact of heating effect and wall proximity on flow characteristics and aerodynamic *** results indicated that the stability of the flow was enhanced as the gap ratio decreased or the heating ratio *** the calculation of enstrophy,it was found that the strength of shedding vortices weakens with a decrease in gap ratio or an increase in heating ***,the mean drag coefficient decreases as the heating ratio increases or the gap ratio *** contrast,the mean lift coefficient initially decreases and then increases as the gap ratio ***,the drag reduction mechanism was analyzed by examining the pressure distribution on the surface of the cylinder.

关键词： compressible flow wall proximity heating effect stability enstrophy

compressible flow characteristics around a biconvex arc airfoil in a channel

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Propulsion and Power Research 2014年第1期3卷 29-40页

作者： Md.Abdul Hamid A.B.M.Toufique Hasan S.M.Alimuzzaman S.Matsuo T.Setoguchi Department of Mechanical Engineering Bangladesh University of Engineering and Technology(BUET)Dhaka-1000Bangladesh Department of Advanced Technology Fusion Saga UniversitySaga 8408502Japan

Shock wave-boundary layer interactions(SWBLI)are observed in several practical high-speed internal flows,such as compressor blades,turbine cascades,nozzles and so *** induced oscillations(SIO),aerodynamic instabilities so-called buffet flows,flutter,aeroacoustic noise and vibration are the detrimental consequences of this unsteady shockboundary layer *** the present study,a numerical computation has been performed to investigate the compressible flow characteristics around a 12%thick biconvex circular arc airfoil in a two dimensional *** averaged Navier-Stokes equations with two equation k-ωshear stress transport(SST)turbulence model have been applied for the computational *** flow field characteristics has been studied from pressure ratio(ratio of back pressure,pb to inlet total pressure,p01)of 0.75 to *** present computational results have been compared and validated with the available experimental *** results showed that the internal flow field characteristics such as shock wave structure,its behavior(steady or unsteady)and the corresponding boundary layer interaction are varied with pressure ***-excited shock oscillation was observed at certain flow ***,the mode of unsteady shock oscillation and its frequency are varied significantly with change of pressure ratio.

关键词： compressible flow Shock waves Shock induced oscillation Frequency Reynolds-averaged Navier-Stokes(RANS)

Constrained Large-Eddy Simulation of compressible flow Past a Circular Cylinder

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Communications in Computational Physics 2014年第2期15卷 388-421页

作者： Renkai Hong Zhenhua Xia Yipeng Shi Zuoli Xiao Shiyi Chen State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking UniversityBeijing 100871P.R.China. Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871P.R.China

compressible flow past a circular cylinder at an inflow Reynolds number of 2×105 is numerically investigated by using a constrained large-eddy simulation(CLES)*** simulation with adiabatic wall boundary condition and at a free-stream Mach number of 0.75 is conducted to validate and verify the performance of the present CLES method in predicting separated *** typical and characteristic physical quantities,such as the drag coefficient,the root-mean-square lift fluctuations,the Strouhal number,the pressure and skin friction distributions around the cylinder,*** calculated and compared with previously reported experimental data,finer-grid large-eddy simulation(LES)data and those obtained in the present LES and detached-eddy simulation(DES)on coarse *** turns out that CLES is superior to DES in predicting such separated flow and that CLES can mimic the intricate shock wave dynamics quite ***,the effects of Mach number on the flow patterns and parameters such as the pressure,skin friction and drag coefficients,and the cylinder surface temperature are studied,with Mach number varying from 0.1 to *** behaviors of the pressure and skin friction distributions are observed with increasing Mach number and the minimum mean separation angle occurs at a subcritical Mach number of between 0.3 and ***,the wall temperature effects on the thermodynamic and aerodynamic quantities are explored in a series of simulations using isothermal wall boundary conditions at three different wall *** is found that the flow separates earlier from the cylinder surface with a longer recirculation length in the wake and a higher pressure coefficient at the rear stagnation point for higher wall ***,the influences of different thermal wall boundary conditions on the flow field are gradually magnified from the front stagnation point to the rear stagnation *** is inferred that the CLES approach in its current

关键词： compressible flow constrained large-eddy simulation circular cylinder separated flow.

A parallel methodology of adaptive Cartesian grid for compressible flow simulations

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Advances in Aerodynamics 2022年第1期4卷 449-478页

作者： Xinyu Qi Yuchen Yang Linlin Tian Zhenming Wang Ning Zhao College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

The combination of Cartesian grid and the adaptive mesh refinement(AMR)technology is an effective way to handle complex geometry and solve complex flow *** high-efficiency Cartesian-based AMR libraries have been developed to handle dynamic changes of the grid in parallel but still can not meet the unique requirements of simulating flow around *** this paper,we propose an efficient Cartesian grid generation method and an information transmission approach for the wall boundary to parallelize the implementation of ghost-cell method(GCM).Also,the multi-valued ghost-cell method to handle multi-value points is improved to adapt to the parallel *** the mentioned methodologies with the open-source library p4est,an automatic and efficient simulation of compressible flow is *** overall performance of the methodology is tested through a wide range of inviscid/viscous flow *** results indicate that the capability and parallel scalability of the present numerical methodology for solving multiple types of flows,involving shock and vortices,multi-body flow and unsteady flows are agreeable as compared with related reference data.

关键词： Cartesian grids AMR Parallel computing compressible flow Immersed boundary method

Upwind and High-Resolution Methods for compressible flow:From Donor Cell to Residual-Distribution Schemes

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Communications in Computational Physics 2006年第2期1卷 192-206页

作者： Bram van Leer W.M.Keck Foundation Laboratory for Computational Fluid Dynamics Department of Aerospace EngineeringThe University of MichiganAnn ArborMI 48108-2140USA

In this paper I review three key topics in CFD that have kept researchers busy for half a ***,the concept of upwind differencing,evident for 1-D linear ***,its implementation for nonlinear systems in the form of highresolution schemes,now regarded as ***,its genuinely multidimensional implementation in the form of residual-distribution schemes,the most recent *** lecture focuses on historical developments;it is not intended as a technical review of methods,hence the lack of formulas and absence of figures.

关键词： Upwind difference high-resolution method compressible flow nonlinear conservation laws

A new dynamic subgrid-scale model using artificial neural network for compressible flow

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Theoretical & Applied Mechanics Letters 2022年第4期12卷 267-274页

作者： Han Qi Xinliang Li Ning Luo Changping Yu LHD Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

The subgrid-scale(SGS)kinetic energy has been used to predict the SGS stress in compressible flow and it was resolved through the SGS kinetic energy transport equation in past *** this paper,a new SGS eddy-viscosity model is proposed using artificial neural network to obtain the SGS kinetic energy precisely,instead of using the SGS kinetic energy *** the infinite series expansion and reserving the first term of the expanded term,we obtain an approximated SGS kinetic energy,which has a high correlation with the real SGS kinetic ***,the coefficient of the modelled SGS kinetic energy is resolved by the artificial neural network and the modelled SGS kinetic energy is more accurate through this method compared to the SGS kinetic energy obtained from the SGS kinetic energy *** coefficients of the SGS stress and SGS heat flux terms are determined by the dynamic *** new model is tested in the compressible turbulent channel *** the a posterior tests,we know that the new model can precisely predict the mean velocity,the Reynolds stress,the mean temperature and turbulence intensities,etc.

关键词： Subgrid-scale kinetic energy Eddy-viscosity model compressible flow

compressible flow SIMULATION AROUND AIRFOIL BASED ON LATTICE BOLTZMANN METHOD

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Transactions of Nanjing University of Aeronautics and Astronautics 2009年第3期26卷 206-211页

作者：钟诚文李凯孙建红卓从山解建飞西北工业大学航空学院南京航空航天大学航空宇航学院

The flow around airfoil NACA0012 enwrapped by the body-fitted grid is simulated by a coupled doubledistribution-function （DDF） lattice Boltzmann method （LBM） for the compressible Navier-Stokes equations. Firstly, the method is tested by simulating the low Reynolds number flow at Ma =0. 5,a=0. 0, Re=5 000. Then the simulation of flow around the airfoil is carried out at Ma：0. 5, 0. 85, 1.2; a=-0.05, 1.0, 0.0, respectively. And a better result is obtained by using a local refined grid. It reduces the error produced by the grid at Ma=0. 85. Though the inviscid boundary condition is used to avoid the problem of flow transition to turbulence at high Reynolds numbers, the pressure distribution obtained by the simulation agrees well with that of the experimental results. Thus, it proves the reliability of the method and shows its potential for the compressible flow simulation. The suecessful application to the flow around airfoil lays a foundation of the numerical simulation of turbulence.

关键词： compressible flow computational fluid dynamics lattice Boltzmann method airfoil body-fitted grid