Effect of inserting obstacle to the velocity in a pipe flow

[wloon]

Hey guys, i want to ask about what the effect of inserting obstacle to the velocity profile of a pipe? I mean when i insert a cube obstacle inside a pipe, how the velocity profile look like? let's say the velocity profile is in laminar flow. Thanks

 

[mpaige1]

You will see a decrease in fluid velocity. As for the laminar flow, it will be laminar but you will have separation points along the outside of the cube. As the fluid separates from the cube, it forms vortices between the laminar flow and the cube surface. Google flow visualization and look at the images posted. It might give you an idea of how fluid will flow over a cube.