Explain please the difference between these jet engine terms:
Obviously they are completely different procedures. The reason I ask this question is because I'm not a native speaker and have some problems differentiating these 2 things.
You don't necessarily have to go deeply into technical details about these two procedures, however it would be welcomed ;)
In general English usage, including in aviation, "rev up" is a verb form describing the act of increasing the speed of something. "Rev up the engine" just means give it a shot of power to make it go faster.
"Run up", as used in this case, is actually a noun, describing a procedure to test an engine against go-no-go criteria. "Do an engine run-up" means perform the run-up procedure, which may include accelerating the engine to a specific speed to put things under a bit of stress, and testing various systems while at speed to detect degraded or failed components or subsystems that are revealed only when under stress.
