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 Oliver August 19, 1998 11:11

F Difference/F Volume/ F Element

Can anyone summarise the difference bewteen the three methods, mentioned above. Also if anyone knowns, where I can obtain information related to the F.V.M, I would appreciate it.

Thanks

Oliver

 Ravi Krishnamurthy August 20, 1998 15:01

Re: F Difference/F Volume/ F Element

Essentially the difference between the three methods is the way the solution is expanded on the finite mesh.

The basis function for the finite diff. method is a Dirac delta function with the solution independent on the neighbourhood mesh.

The Finite vol method has a unit step as the basis function with the solution constant over the mesh volume.

The Finite element basis in general is linear that is the 'hat' function.

Each of the above has a higher degree polynomial for the solution basis. This is altered for each of the above cases when more accuracy is required, like higher order spatial accuracuy by interpolation in F.D/F.V methods and increasing the polynomial fit in the F.E. methos, like quadratic elements.

A good starting point is the general CFD books like the one by Anderson, Tannehill and Pletcher.

Ravi

 Oliver August 21, 1998 07:24

Re: F Difference/F Volume/ F Element