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mick - n/a
14-Jun-06, 09:16 PM
IM just a wondering , in using 5 x 5zr blades in a 900 duct at around 50 hp this should be a good effiecent set up and produce more static thrust.

or am i wrong , in carrying thrust tests considering the results ,they sugest low thrust output.



Using 6 blades will give better results in skirt preasure but will that set up perform better in static thrust tests?



has anybody out their done comparasons tests for both set ups?



and my final food for thought question, a 12 position hub with 6 x4zr blades in a 900 duct 50 hp, how would this compaire.

Nickinoue - n/a
14-Jun-06, 10:04 PM
if u r gunna go with 6 blades u might aswel go with a 9z hub and par blades together, it looks odd but im told it is slightly more effecient cuz theses room for the blades to make eddies without the other blades attacking that i think http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif ?

It also means you can have more blade length and saves u abit of dosh http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif .

6 or 5 blades with 50 hp slightly above a TZR should be more than adiquet. Having more blades will increase cussion performance but the dynamic thrust will surffer.

Nick

tonybroad - n/a
15-Jun-06, 07:40 AM
Hi Mick



What are you getting in your thrust test - A TZR should be able to pull 750+N (170lbs) with a 5/5 or 6/9



Check out the mods and sods bit of my website - i've done a comparison of a 6/9 and 5/5 hascon using the manufacturers software and the 5/5 looks to be far more efficient and absorbs less Hp yet delivers the same rate of flow and static pressure



I've also been doing a bit of thrust testing/tweaking lately and i'm getting what the manufacturers data suggests from my 6/9 Multiwing



I've bought a 5/5 Hasconwing and I'm on the verge of fitting it so i will be able to compare it directly to a 6/9 Multiwing - watch this space !



With the 4Z's i reckon you will effectivley lose the amount of working blade 'cos the 12 hub is a larger diameter and the blades are generally smaller - i don't have the multiwing software so this is just my thoughts



Good Luck



Tony

mick - n/a
15-Jun-06, 01:10 PM
hi tony its ricky

we are only getting 625nm on a static thrust test so we are quite low on thrust but it doesnt seem to be slowing the craft down,but if i can get the thrust right then we should be singin http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif

tonybroad - n/a
15-Jun-06, 02:06 PM
Hi Ricky



don't forget you're down on compression on one cylinder - get that sorted before you go trying diffrent fans



625N is very respectable



Tony

mick - n/a
19-Jun-06, 10:16 AM
hi tony its ricky

we have tested both silinders and both seem to have the same compression witch is 110. i have now higherd the splitter plate by 1 inch to try over come drag. now the only other thing we can think of to do is try a diffrent fan setup and hope for the best http://hovercraft.org.uk/images/icons/smiley_icons/icon_razz.gif cheers rick

mick - n/a
19-Jun-06, 10:21 AM
oh i forgot to add i did a thrust test the other day and i was pulling 165 pounds but tht was on very long grass im not sure if the grass would effect the static thrust thanks rick