摘要
基于深度强化学习方法(deep reinforcement learning,DRL),采用一对施加在圆柱表面的质量流量为零的射流,对Re=200,400,间隙比G/D=0.5,0.7,1.0,1.5,2.0的近壁圆柱进行主动流动控制研究。通过DRL方法获得不同参数下的射流控制策略与相应控制效果,并讨论了不同射流位置(90°,270°)、(90°,320°)、(90°,360°)对控制效果的影响。研究发现Reynolds数、间隙比和射流位置都对控制效果有重要的影响。射流位置为(90°,270°)时通过DRL控制可以有效降低阻力系数及其波动,控制后的圆柱尾迹被拉长且圆柱前后压差降低。射流位置为(90°,320°)和(90°,360°)的控制效果相似,都能使平均阻力系数有所降低,但控制位置的不对称性导致控制后的阻力系数波动较大。Reynolds数和间隙比的增大会增加控制射流的质量流量水平,在相同条件下,使用(90°,270°)的射流位置可以用相同的质量流量得到更好的控制效果。
Based on the deep reinforcement learning(DRL)method a pair of jets with zero mass flow applied to the cylindrical surface was used to study the active flow control of a near-wall cylinder for Re=200,400,and the gap ratio G/D=0.5,0.7,1.0,1.5,2.0.The jet control strategies and corresponding control effects under different parameters were obtained by the DRL method,and the control effects of different jet positions(90°,270°)、(90°,320°)、(90°,360°)were discussed.It is found that the Reynolds number,gap ratio and jet position all have important influence on the control effects.When the jet position is(90°,270°),the drag coefficient and its fluctuation can be effectively reduced by DRL control,the controlled cylinder wake is elongated and the pressure difference between the front and rear of the cylinder is reduced.The control effects of the jet positions(90°,320°)and(90°,360°)are similar,which can reduce the average drag coefficient,but the drag coefficient after control fluctuates greatly due to the asymmetry of the control positions.The increase of Reynolds number and gap ratio will increase the mass flow level of the control jet.Under the same conditions,using the jet position of(90°,270°)can get better control effects with the same mass flow rate.
作者
王强
王伯福
刘宇陆
WANG Qiang;WANG Bo-fu;LIU Yu-lu(School of Mechanics and Engineering Sciences,Shanghai University/Shanghai Institute of Applied Mathematics and Mechanics,Shanghai 200072,China;School of Science,Shanghai University of Applied Sciences,Shanghai 201400,China;Shanghai Frontiers Science Base for Mechanoinfomatics,Shanghai 200072,China)
出处
《气体物理》
2023年第2期56-65,共10页
Physics of Gases
关键词
近壁圆柱绕流
流动控制
减阻
间隙比
射流位置
flow around a cylinder near the wall
flow control
drag reduction
gap ratio
jet position
