This very important concept is what I call Obi-Wan Kenobi concept. Remember the training scene: “Luke, Trust your feelings.”. Same here. By other words, an engineer must “feel” things and physical events.
Datacenter are plants with many fields of technology. One cannot master all aspects of the equipment. There is however a trick to at least understand or “feel” physic behind hydraulic and electricity when mastering one of them: the similarity :
In both cases, similarities can be used.
Pressure is like tension. Flow rate is like intensity.
Power from hydraulic is related to pressure, power from electricity is related to tension.
Heat generated by flow rate in pipes (friction) is related to flow rate and pipe resistance. Heat generated by electricity is related to intensity and cable resistance.
The flow rate is related to pipe resistance and pressure applied. The intensity is related to cable resistance and tension applied.
When a pipe divide and reach multiple points (without taking into account pipe friction and gravity), all these points share the same pressure. When a cable divide and reach multiple points (without taking into account cable resistance and electric fields), all these points share the same tension.
A tank full of water and opened at the bottom will empty at an exponential decreasing speed (the less water in the tank, the less pressure to push water outside, and the less flow rate).
A capacitor full of energy linked to a circuit will discharge at an exponential decreasing speed (the less energy, the less tension to push electrons to move).