In this section we modify the fluid system to allow for flow. The flow is steady-state which means it is constant over time for a given fluid system. To describe flow, kinetic energy-density, in addit...In this section we modify the fluid system to allow for flow. The flow is steady-state which means it is constant over time for a given fluid system. To describe flow, kinetic energy-density, in addition to pressure and gravitational potential energy-density, is added to the equation which describes energy-density conservation. We also look dissipative effects of resistance to flow which convert mechanical energy to thermal energy, and a source which adds energy to the fluid flow system, a pump.