Talk:Stagnation pressure

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I don't understand why the thermal form of stagnation pressure is presented here. Stagnation pressure is the pressure a moving fluid would have if it is stagnated or stopped. It is difficult to clearly communicate this in a formula that makes no reference to velocity. Stagnation pressure is constant in an eisentropic flow. P_s = P + ρv² where P_s is the stagnation pressure, P is the pressure at a given velocity, ρ is density and v is velocity. Granted that any change in v must be accompanied by a change in temperature T, but to someone that is un initiated in the art of fluid dynamics this is probably not obvious. This is especially true when working with an incompressible fluid such as water.

Adding heat to a moving gas at constant pressure and velocity reduces its density and stagnation pressure. Conversley cooling a moving gas at constant pressure and velocity has the oposite effect. US Patent 5,083,429describes a device that uses this effect to extract power.