The present work is dedicated to the application of the recently developed （δ＋ -SPH） scheme to the self-propulsive fishlike swimming hydrodynamics. In the numerical method, a particle shifting technique （PST） is...The present work is dedicated to the application of the recently developed （δ＋ -SPH） scheme to the self-propulsive fishlike swimming hydrodynamics. In the numerical method, a particle shifting technique （PST） is implemented in the framework of δ-SPH, combining with an adaptive particle refinement （APR） which is a numerical technique adopted to refine the particle resolution in the local region and de-refine particles outside that region. This comes into being the so-called δ＋- SPH scheme which contributes to higher numerical accuracy and efficiency. In the fishlike swimming modeling, a NACA0012 profile is controlled to perform a wavy motion mimicking the fish swimming in water. Thanks to the mesh-free characteristic of SPH method, the NACA0012 profile can undergo a wavy motion with large amplitude and move forward freely, avoiding the problem of mesh distortion. A parallel staggered algorithm is adopted to perform the fluidstructure interaction between the foil and the surrounding fluid. Two different approaches are adopted for the fishlike swimming problem. In Approach 1, the foil is fixed and flaps in a free stream and in Approach 2, the wavy foil can move forward under the self-driving force. The numerical results clearly demonstrate the capability of the δ＋ -SPH scheme in modeling such kind of self-propulsive fishlike swimming problems.展开更多
基金funded by the National Natural Science Foundation of China (U1430236)the Fundamental Research Funds for the Central Universities (HEUGIP201701)
文摘The present work is dedicated to the application of the recently developed （δ＋ -SPH） scheme to the self-propulsive fishlike swimming hydrodynamics. In the numerical method, a particle shifting technique （PST） is implemented in the framework of δ-SPH, combining with an adaptive particle refinement （APR） which is a numerical technique adopted to refine the particle resolution in the local region and de-refine particles outside that region. This comes into being the so-called δ＋- SPH scheme which contributes to higher numerical accuracy and efficiency. In the fishlike swimming modeling, a NACA0012 profile is controlled to perform a wavy motion mimicking the fish swimming in water. Thanks to the mesh-free characteristic of SPH method, the NACA0012 profile can undergo a wavy motion with large amplitude and move forward freely, avoiding the problem of mesh distortion. A parallel staggered algorithm is adopted to perform the fluidstructure interaction between the foil and the surrounding fluid. Two different approaches are adopted for the fishlike swimming problem. In Approach 1, the foil is fixed and flaps in a free stream and in Approach 2, the wavy foil can move forward under the self-driving force. The numerical results clearly demonstrate the capability of the δ＋ -SPH scheme in modeling such kind of self-propulsive fishlike swimming problems.
