[hancock]

The relevance of following mathematical statements to practical problems

1)“Inviscid flow” with a given Reynolds number
2) “Inviscid flow” with no slip wall boundary condition.

Also how can we simulate this in CFD?

Any references will be useful.

[LuckyTran]

For engineering problems inviscid means you set viscosity to 0 or do not include the viscous force in your calculation.

Mathematically, inviscid means that viscous forces are negligible (i.e. very small). Although viscosity being equal to 0 is sufficient to show that a flow is inviscid in the classical sense, a finite Reynolds number is possible when one considers that a non-zero viscosity together with infinite strain (i.e. ridiculously high velocity gradients) can dissipate energy at a finite rate. There are practical applications for these flows in astrophysics for example where velocity approaches the order of the speed of light. You typically don't simulate these via traditional CFD like RANS with a turbulence model because handling infinite shear stress is not trivial.

[FMDenaro]

Originally Posted by hancock

The relevance of following mathematical statements to practical problems

1)“Inviscid flow” with a given Reynolds number
2) “Inviscid flow” with no slip wall boundary condition.

Also how can we simulate this in CFD?

Any references will be useful.

Statements 1) and 2) are wrong. Inviscid flows means the viscosity and conducibility are assumed zero. Therefore, Reynolds and Peclet numbers are infinite.


From a mathematical side, the character of the PDEs systems changes and you have to work with a system of hyperbolic equations.






There are several CFD textbooks (Leveque, Hirsch, Toro...) wherein you can study the formulations.