AzfromOz said:
my "whirlpool" is achieved by vigorous stirring...
Before I used to have a pump I'd do the same, the chiller didn't get in the way. In fact chilling in still water is going to be far less effective since you want to be getting as much hot wort in contact with as much cold metal as possible, if still it will still "radiate" heat but the exchange rate will drop significantly as what's in contact with the chiller has already cooled.
Not unlike why burns should be treated with running water, not still.
Sounds like you want to have a nice trub cone form without interference from the chiller, so to whirlpool without the chiller in the way here's what I'd personally do without a pump:
1. Drop chiller in @ 15 min
2. At flame out, drop hop.
3. Turn on water, start stirring, stop at ~78-80C (you will lose a few more degrees to water in the chiller)
4. Wait X minutes
5. Turn water on, stir your tits off until chilled
6. Remove chiller, give one last big stir, wait for trub to settle
7. Collect final wort