The issue of hydrostatic head
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Help: When gas flows through a pipe, as the flow velocity increases, the static head decreases. And the hydrostatic head is the pressure caused by its own gravity. But the gravity of the gas here hasn’t changed; why then does it decrease? That is: How is the static head of the gas in the pipeline generated?
Static head is the static pressure energy possessed by a unit weight of fluid. It is related not only to weight but also to pressure
The static head of a gas is the relative static pressure per unit volume of gas, and its value equals the relative pressure (i.e., gauge pressure) of the gas inside and outside the pipe. The energy of a gas = potential energy + kinetic energy. In steady flow, as the flow velocity increases, the kinetic energy rises while the potential energy decreases (the static pressure head decreases). ——Energy conservation!
Reply to 3# txa001: It should be taken into account that the transmission equipment also continues to supply energy as the fluid accelerates; therefore, it can be assumed for a short period of time that the potential energy remains constant. The increase in velocity is exactly equal to the energy supplied by the transmission equipment. So why then does the static head decrease at this point?