|
|
investigation on the mechanism of drag modification over triangular riblets
|
|
|
|
|
نویسنده
|
zhang m. m. ,zhang z. l. ,zhao m.
|
منبع
|
journal of applied fluid mechanics - 2020 - دوره : 13 - شماره : 4 - صفحه:1093 -1106
|
چکیده
|
This paper presents experimental and numerical investigations on the modification of local spanwise skinfriction over triangular riblets under the total drag reduction condition. specifically, the mean and fluctuating vortical flow fields were measured using 2-components x-wires and computed using les, respectively. besides, the relationship between local skin-friction along the riblet spanwise and associated vortex evolution was also built using the vortex dynamic method. based on these results, it was found that, compared with the smooth case, the impaired and enhanced vortex strength, and resultant viscous diffusion/energy dissipation, determined the reduction and augment of the viscous drag force over the local spanwise riblet groove, i.e., decreasing and increasing cases of local drag, respectively. furthermore, the mean normal diffusion fluxes of normal and spanwise vorticities contributed more to the viscous drag under these two cases. correspondingly, the relevant flow physics related to these phenomena was discussed in detail.
|
کلیدواژه
|
riblets ,drag reduction ,local skinfriction ,vortex dynamic method
|
آدرس
|
chinese academy of sciences, institute of engineering thermophysics, key laboratory of wind energy utilization, dalian national laboratory for clean energy, china, chinese academy of sciences, institute of engineering thermophysics, key laboratory of wind energy utilization, dalian national laboratory for clean energy, china, tianjin university, school of mechanical engineering, department of mechanics, china
|
پست الکترونیکی
|
ming.zhao@tju.edu.cn
|
|
|
|
|
|
|
|
|
|
|
|
Authors
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|