ELi5 How do people control which direction to move liquid/gas in a pipe


Like how do they choose to move from left to right or bottom to top

In: 1

Pressure. You push the gas/liquid in from one end, the only direction it can go is towards the other end. If you need more distance/speed, you push harder.

Fluids (gas and liquid) move from high pressure to low pressure.

To get a fluid to move through a pipe you either shove more in at one end to increase pressure at the end you want it to flow from (water pipes, gas mains), or you suck some out at the other end to decrease pressure at the end you want it to flow to (vacuum cleaner, vacuum tube delivery systems)

Just pressure. The gas or liquid is at a high pressure at the source, so when a valve is opened, introducing a low-pressure enivronment, it moves toward low pressure.

For example, a propane tank. Propane is normally a gas at regular temps, but the propane in that canister is liquid. It is trying to go back to a gas, which creates pressure. This is what happens when you heat water in an enclosed container… it is at a temp where it wants to expand into a gas, but there isn’t enough room. Then, when you open the valve on the propane tank, suddenly there is a low pressure environment for the gas to expand into.