Effect of Shear Flow on Flow Characteristics of The PTC Cylinder

Abstract

In this paper, FLUENT software was used to simulate the flow characteristics of the passive turbulence control (PTC) cylinder in shear flow field. In the range of Reynolds number 3.5×10⁴ ⩽Re⩽7.0×10⁴, shear rate (K) and Reynolds number (Re) can affect the dynamic characteristics of the PTC cylinder. The results show that, in shear flow field, the trends of C_Drms and C_Drms of the PTC cylinder are the same as those in uniform flow field. When the parameter K is constant, C_Drms and C_Drms decrease with the increase of the parameter Re. When Re is constant, both C_Drms and C_Drms decrease with the increase of K. When Reynolds number is 3.5×10⁴, the results about the wake shape of the PTC cylinder in the shear flow field show that the characteristics of the incoming flow will influence the pressure distribution to a greater extent and offset the influence of partial randomness to a certain extent. Compared with the randomness of KH instability of shear layer in the symmetric flow field, the difference of pressure distribution on the upper and lower surfaces of a cylinder in the shear flow field makes it easier to excite the periodic vorticity phenomenon.