What is Momentum Flowrate?
Momentum flowrate is the rate of transport of momentum across a unit area perpendicular to the direction of fluid flow. The momentum flowrate is involved in the overall conservation of momentum that must be satisfied across any arbitrary control volume within the flow system, such as an individual finite volume cell in a computational fluid dynamics model.
The flow of momentum is responsible for the intertial forces that arise in a fluid dynamics system. These can be expressed for inviscid flow by the Euler equations, or in the more general case by the Navier-Stokes equations.