- #36
256bits
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sophiecentaur said:Except that the load / speed characteristic of the motor would affect the actual change in mass flow of the air.
You have two engines involved. The Fan drives the air and then the heater is a further energy source so you have a heat engine - it's like a very feeble jet engine in more or less every respect.
I think that the hair dryer result they got is only a special case and it 'just happens' that there was no detectable difference. That could be confusing the wider issue.
A feeble jet engine is what I was tying to point out in post #6.
I expected there to be some extra thrust, but perhaps the compression of the air from the fan is just not enough, since only the friction from the interior walls and parts would be responsible for any back pressure.