A flow in which viscous effects can be neglected is known as inviscid flow. At high Reynolds numbers, flow past slender bodies involve thin boundary layers. Viscous effects are important only inside the boundary layer and the flow outside it is nearly inviscid. If the boundary layer is not separated then the inviscid flow model can be used to predict the pressure distribution with reasonable accuracy.
The governing equations for inviscid flow are obtained by discarding the viscous terms from the Navier-Stokes equations
- Continuity equation
- Momentum equation
- Energy equation