基于格子Boltzmann方法的船舶风力助推转子绕流特性

风力转子推进装置节能环保,降低推力成本,有利于船舶行业的绿色发展。基于多松弛格子Boltzmann方法,对并列风力助推转子绕流进行数值模拟。首先模拟单圆柱绕流的流动特性,以验证程序的可靠性,重点探究双圆柱的间距比和转速比对圆柱绕流特性的影响。获取圆柱的升阻力系数以及尾流流型,验证临界转速比的存在。结果显示:旋转可以有效地抑制涡的生成和脱落,当转速比达到临界转速比时,漩涡彻底消失,流场变得稳定;时均升力系数的绝对值和时均阻力系数随转速比的增大分别增大和减小。

Flow characteristics analysis of marine wind-driven rotor sails based on lattice Boltzmann method

The wind propulsion device is energy-saving and environmentally friendly,reduces thrust costs,and is conducive to the green development of the ship industry.Based on the multiple-relaxation-time lattice boltzmann method,the flow around parallel wind-driven rotor is numerically simulated in this paper.First,the flow characteristics of a single cylinder was simulated to verify the reliability of the program.Then,the effect of the spacing ratio and rotational speed ratio on the flow characteristics of the double cylinder was studied.The lift coefficient,drag coefficient and wake flow patterns of the cylinder were obtained,and the existence of critical rotational speed ratio was verified.The results show that the rotation of the cylinder can suppress vortex shedding effectively;the absolute value of the mean lift coefficient increases with the increase of the rotational speed ratio,while the trend of the mean drag coefficient is opposite.The purpose of this paper is to provide reference for the control and design method of wind-driven rotor sails.