[Stoves] Reminder needed please

[neiltm at uwclub.net]

Could someone please possibly remind me who and when was the thread that 
shared experiments with a NDTLUD where a static 'fan blade' was utilised 
at the top of the stove to introduce swirl for better air mixing, and 
also some holes half way up the burn chamber?  Some pictures were also 
shared.

I have the posts, it is just finding them.

Thanks,   Neil Taylor