j_m(t,l) = j_m = \rm const

In case of a  Pipe Flow with constant cross-section area  it simplifies to: 

\dot m(t,l) = \dot m = \rm const

See also

Physics / Mechanics / Continuum mechanics / Fluid Mechanics / Fluid Dynamics / Fluid Flow / Pipe Flow / Pipe Flow Dynamics / Pipe Flow Simulation 

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