Estudo dos efeitos da estratificação na supressão da turbulência em um escoamento de Couette plano

Abstract

The bounded layer is the region after the surfasse that is affected by the presence of the same. Shortly after sunset, the earth’s surfasse begins to coolby the emission of long-wave radiation, this processis known as termal stratifcation. Na alternative that has been widely used to study the effects of stratifcation on turbulence is the use of numerical experiments, this is because they have a lower cost than physical experiments, in addition to being idealized, controled and not subject to interference from phenomena on a larger scale than the turbulent one. The computational domain has 12.56m in x, 2m in y, and 8.378 in z. The computational domain has a total of 1629029 points where the equations were discretized by the fnite volume method. After the formation and establishment of the vórtices (frst7200s), the lowe rsurface of the domain is cooled at a constant rate of 0.5K h−1 to 64800 s. Over the cooling time, it was observed that the reduction of turbulence until its colapse and the presence of intermittence phenomena were observed.