The words clearly have a similar meaning. But I think there must be a subtle difference.
e.g. You get a "flight simulator", but an "ipad emulator".
Both are pieces of software for replicating the behaviour of something. So why are the words not interchangable?
Best Answer
โ "Emulator": "Comparison with Simulation", Wikipedia
See also the Stack Overflow question "What's the difference between emulation and simulation?"