Hey guys I am looking at a turbulent shear flow, where x1 is the streamwise direction, x2 and x3 represent the spanweise directions. In streamwise direction the domain in not bounded, thus infinite, is it possible to therefore assume that all the fluctuations are independent of x1? meaning generally speaking d/dx1=0?
Hey guys,
Let's assume a plane Couette flow. It is described as the motion of a fluid between two plates, of which at least one plane moves with a constant velocity in the streamweise direction. Because of the motion of the plate the fluid inbetween begins to build vortices, similar to the Taylor-Green vortices. I am currently asking myself, if these vortices vanish over the time, since the motion of the plate is constant or if the vortices remain, since the plate is moved constantly.
I have tried to solve the Navier-Stokes-equation for fluctuations in a plane Couette flow, and I obtained decaying solutions for these vortex-fluctuations as e^{-(a+b)t}. I am not sure about the physicallity though, since I expected the vortices to not decay.
Do you have any ideas about what is true?
This is actually the second time a question such as this has stopped me in my tracks. I have the answer but I have no similar questions worked through with a clearer methodology so either helping me break down what's going on here or giving me some advice as to what to go and revise would be appreciated. (I'm aware that I'm ignorant of my ignorance atm)
https://ibb.co/bAVLWb
My Issue is with the answers on the third 'page'. Namely, everything apart from the 100kN
How much shear does fluid encounters during flow through a pipe ? How to calculate it ?
The opening is a razor blade riding on the surface of a rotating embossed cylinder.
Can anyone give an explanation as to why there is zero shear stress in the center of laminar flow inside a cylindrical pipe, and maximum shear stress at the boundaries?
Here is a graph presented that depicts it visually: http://imgur.com/a/KOX3y
Intuitively, I would think shear stress would be the greatest in the middle, and zero at the boundaries. I'm thinking about it in this sense: In the middle, two layers of the fastest moving fluid are acting on the center layer exerting the most shear, and at the boundaries, there is little to no movement, hence no shear stress. Am I thinking about shear all wrong?
Hey guys I am looking at a turbulent shear flow, where x1 is the streamwise direction, x2 and x3 represent the spanweise directions. In streamwise direction the domain in not bounded, thus infinite, is it possible to therefore assume that all the fluctuations are independent of x1? meaning generally speaking d/dx1=0?
Hey guys,
Let's assume a plane Couette flow. It is described as the motion of a fluid between two plates, of which at least one plane moves with a constant velocity in the streamweise direction. Because of the motion of the plate the fluid inbetween begins to build vortices, similar to the Taylor-Green vortices. I am currently asking myself, if these vortices vanish over the time, since the motion of the plate is constant or if the vortices remain, since the plate is moved constantly.
I have tried to solve the Navier-Stokes-equation for fluctuations in a plane Couette flow, and I obtained decaying solutions for these vortex-fluctuations as e^{-(a+b)t}. I am not sure about the physicallity though, since I expected the vortices to not decay.
Do you have any ideas about what is true?
