Search found 3 matches

by Synchro
Thu Aug 23, 2007 10:19 am
Forum: Newcomers Briefing Room
Topic: Circular shrouded blades? Why Not?
Replies: 5
Views: 2385

Probably. My main thing was really to see fans like the impeller the TMD ones use. It would seem an obvious way to improve throughput, pressure and noise, I just wonder why it hasn't been done.
by Synchro
Thu Aug 23, 2007 9:26 am
Forum: Newcomers Briefing Room
Topic: Circular shrouded blades? Why Not?
Replies: 5
Views: 2385

Ah, I'd seen them a while back but not noticed that they had the shrouded blades as well as tip driving. Seems dumb that their sizes are off - I guess they need to make their corner drivers smaller. Might be interesting to see a centre-driven fan using it though. As for edge bearings, it would seem ...
by Synchro
Thu Aug 23, 2007 8:15 am
Forum: Newcomers Briefing Room
Topic: Circular shrouded blades? Why Not?
Replies: 5
Views: 2385

Circular shrouded blades? Why Not?

I know that fans generate noise at the blade tips, that pressure is reduced by leakage between the blade tips and surround. It occurred to me - why not attach blade ends to a circular shroud and rotate the whole thing? This would remove tip noise altogether (because there aren't any), reduce leakage...