Numerical Simulation of Two-Dimensional Flow over Three Cylinders by Lattice Boltzmann Method

【摘要】 <正> The numerical simulation using the multiple relaxation time lattice Boltzmann method (MRT-LBM) iscarried out for the purpose of investigating the two-dimensional Bow around three circular cylinders.Among these threecircular cylinders, one of the three cylinders on which a forced in-line vibrating is used to do this research and attemptto find out the effects of the moving cylinder and the other two rigid cylinders on the wake characteristics and vortexformation.As a benchmark problem to discuss the problem of lift coefficient r.m.s for these cylinders with spacing ratiosT/D between other rigid side-by-side cylinders, and the calculation is carried out with two compared cases at Reynoldsnumber of 100, two of the cylinders are rigid and the other one is an in-line vibrated cylinder lying downstream, inaddition, forced vibrating amplitude and frequency are A/D = 0.5 and f_v= 0.4 (where A is the forced amplitude, D isthe cylinder diameter, and f_v stands for the vibrating frequency, respectively).The calculated results not only indicatethat the spacing ratios T/D (T is the center-to-center spacing between the two upstream cylinders) have influence onthe wake patterns and the formation of vortex shedding, but also analyze the lift coefficient r.m.s for the three cylinderswith the spacing ratios S/D (where S is the center-to-center spacing between the center of upstream two side-by-sidecylinders and downstream cylinder).更多还原

【Abstract】 The numerical simulation using the multiple relaxation time lattice Boltzmann method (MRT-LBM) is carried out for the purpose of investigating the two-dimensional Bow around three circular cylinders.Among these three circular cylinders, one of the three cylinders on which a forced in-line vibrating is used to do this research and attempt to find out the effects of the moving cylinder and the other two rigid cylinders on the wake characteristics and vortex formation.As a benchmark problem to discuss the problem of lift coefficient r.m.s for these cylinders with spacing ratios T/D between other rigid side-by-side cylinders, and the calculation is carried out with two compared cases at Reynolds number of 100, two of the cylinders are rigid and the other one is an in-line vibrated cylinder lying downstream, in addition, forced vibrating amplitude and frequency are A/D = 0.5 and f_v= 0.4 (where A is the forced amplitude, D is the cylinder diameter, and f_v stands for the vibrating frequency, respectively).The calculated results not only indicate that the spacing ratios T/D (T is the center-to-center spacing between the two upstream cylinders) have influence on the wake patterns and the formation of vortex shedding, but also analyze the lift coefficient r.m.s for the three cylinders with the spacing ratios S/D (where S is the center-to-center spacing between the center of upstream two side-by-side cylinders and downstream cylinder).更多还原