Drag Force at very very high Renolds Number ?

1. Jul 25, 2011

sunnyguha

What is the expression for Drag Force at very very High Renolds Number flow (>10^6)
as we know the expression
for drag force between Re1 and Re10^5 = 0.5kpAv^2
but this isnt valid aft 10^5 ..
so .....

2. Jul 25, 2011

There isn't any general equation for drag at any value of Reynolds number to be honest. Even the equation you quoted depends on a a coefficient that varies wildly for different environments and geometries.

Let me instead pose this question: what exactly is the situation that you are in? What are the details of the system? How high do you consider "very very high," because 10^6 is actually pretty low for quite a few situations.

3. Jul 25, 2011

sunnyguha

as in lets take an example for a sphere of radius 0.1 m moking with the speed of 100 m/sec
Renolds = pv/viscosity which gives 10^7

so what wud be the drag force calculating expression for this situation

4. Jul 25, 2011