[samina]

hi friends,
Can anyone tell me about some efficient n stable numerical schemes to solve Boundary Layer Flow Problem. thanks
With profound regards.
samina

[leflix]

Originally Posted by samina

hi friends,
Can anyone tell me about some efficient n stable numerical schemes to solve Boundary Layer Flow Problem. thanks
With profound regards.
samina

Hi Samina

which kind of boundary layer problem?
If it is 2D and over a flat plate, solving Blasius equation is straightforward.
check this :http://moon.pr.erau.edu/~gallyt/ae30...ricBlasius.pdf
If the geometry is more complex than flat plate, use any good Navier-Stokes solver.

[samina]

thanks leflix,
you suggested a goood link.
My problem is not on an easy geometry, its the BVP for the flow over an expanding stretching cylinder, (in cylindrical coordinates) 3D geometry

[leflix]

Originally Posted by samina

My problem is not on an easy geometry, its the BVP for the flow over an expanding stretching cylinder, (in cylindrical coordinates) 3D geometry

Then the only outcome is to solve the full NS equations. Refine the grid near the wall. Hope the Reynolds number is not too high....

[samina]

One more issue,I have NS eq of order four, while i have only three boundary conditions..
What should i do for the missing condition.
Regards

[cfdnewbie]

Originally Posted by samina

One more issue,I have NS eq of order four, while i have only three boundary conditions..
What should i do for the missing condition.
Regards

What kind of formulation of the NS equations do you have?? They are second order PDEs....

[samina]

Obviously, 2nd order PDEs (NS eqs for the viscous fluid).
but when i convert these equations to ODE, by using similarity transform for the stretching surfaces, order of the differential equation is raised by 1, so it becomes 3rd order ODE.
And when i solve the same problem for the 2nd grade fluid, i get ODE of order 4

[cfdnewbie]

Originally Posted by samina

Obviously, 2nd order PDEs (NS eqs for the viscous fluid).
but when i convert these equations to ODE, by using similarity transform for the stretching surfaces, order of the differential equation is raised by 1, so it becomes 3rd order ODE.
And when i solve the same problem for the 2nd grade fluid, i get ODE of order 4

Sorry, I don't know what a 2nd grade fluid is, but if you have 3 BCs from the similarity ( I assume what you are doing is similar to the classical blasius solution, which is a 3rd order PDE), then the last one has to come from this 2nd grade fluid, whatever that might be