ORIGINAL: rcdriver22
ORIGINAL: BJ64
Got any links there Xair?
I've been Googling like mad, but haven't come across anything all that useful so far...
BJ
The tube reduction in dia is usually nominal 5-7%, the spacing betweem is more critical. If you have no test bed for thrust try reading RCJI articles about 6 yrs ago or join GTBA for $20.
Paul
Um..."tube reduction 5-7%" - from what to start with? Does that mean that the tube is tapered? If so, bigger diam at the Turbine exhaust and smaller diam end at the rear of the 'craft?
Is there any particular formula for what the dimensions of the bellmouth should be?
And when you say 'spacing in between', do you mean the air-gap between the Turbine's exhaust and the start (bellmouth) of the exhaust tube?
BJ