Calculating thrust

[Stumpalump]

I'm trying to fiqure out what size fan would be best. I'm looking at this one at lowes but don't know how to convert CFM to thrust.
https://www.lowes.com/pd/Utilitech-...-_-4755305:Utilitech_Pro&CAWELAID=&am p;amp;kp id=47553 05&CAGPSPN=pla&store_code= 2272&amp ;amp;k_click ID=5b4bcf6f-3da0-47bf-9c17-879e51eb3910&gclid=EAIaIQobChMI_sHWt7K Z2gI ViV9-Ch1hRQkqEAQYAyABEgInvPD_BwE

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I think the Honda EU2000 has enough power for it.

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The canoe is a big heavy 18 footer. I found a nice 3' shop fan at Harbor freight and with my 20% coupon it's not to expensive but I'm back to my question on how to calculate the thrust into a meaningful number. The 3 footer might be too big.

 

[Sea Rider]

I would start with the larger fan, fan will take its time to power a canoe from a dead stop to displacement speed, now imagine a much smaller fan doing same job..

Happy Boating

 

[GA_Boater]

Don't know nuttin' to convert CFM to thrust, but if the guard grids are removed thrust should be increased. And fish filleting will be fast and hopefully, painless.

 

[garbageguy]

Should we be considering what the date is?

 

[GA_Boater]

Should we be considering what the date is?

Nah - This will work tomorrow. :lol:

 

[jbuote]

Hmm...
I suppose you could go with a large oscillating fan. That way you could have power steering too!
Just a thought.. :laugh:

 

[Stumpalump]

Hmm...
I suppose you could go with a large oscillating fan. That way you could have power steering too!
Just a thought.. :laugh:

I already figured out steering.

https://www.iboats.com/shop/boat-se...wood-clamp-on-boat-seat-swivel-swivl-eze.html

If they made a reclining bracket I'd have tilt and trim.

 

[jbuote]

If they made a reclining bracket I'd have tilt and trim.

Might consider using these between swivel base and fan then?

https://www.iboats.com/shop/boat-se...nch-silver-boat-seat-hinge-9-1-2-in-pair.html

 

[Ned L]

Very good!!!!

 

[Texasmark]

Should we be considering what the date is?

Good point. Apparently others have the same problem as I do.....get to reading the question and don't pay attention to the posting date.

 

[Maclin]

You would need a bigger fan with that much weight, which would need more power, which would need a bigger generator, which would weigh more and you would need a bigger fan, and a bigger generator.... you're gonna need a bigger boat.

 

[GA_Boater]

You would need a bigger fan with that much weight, which would need more power, which would need a bigger generator, which would weigh more and you would need a bigger fan, and a bigger generator.... you're gonna need a bigger boat.

Or we could wait until Stump concludes 362 days of testing. LOL

 

[Horigan]

Agreed. I calculated it for the fun of it. The Lowes fan linked (7860 CFM and 24" blade) will only produce 13.5 lbs of thrust.

Here's the question for those interested.
Thrust = (Density) x (CFM^2) / ((Pi) x (r^2)) Remember to convert your units.

 

[Maclin]

Agreed. I calculated it for the fun of it. The Lowes fan linked (7860 CFM and 24" blade) will only produce 13.5 lbs of thrust.

Here's the question for those interested.
Thrust = (Density) x (CFM^2) / ((Pi) x (r^2)) Remember to convert your units.

Who invited Archimedes? :lol:

 

[Scott Danforth]

this is the fan that should be used

 

[Old Ironmaker]

The only problem with the formula is calculating density. Fairly simple in an operating Blast Furnace. 790 feet per second with a 6" Tuyere @ 35psi, dependant on Blowpipe size. You are either need a bigger fan or smaller boat to move it. I saw a Land Shark here the other day.

 

[bassman284]

Or we could wait until Stump concludes 362 days of testing. LOL

That's my plan.

 

[fishrdan]

Slight design flaw... The fan would be much more efficient in the water, with the added bonus of electro-shocking the fish your after.

[DISCLAIMER: Check your local electro-shock fishing regulations before use.]

 

[Doh]

Agreed. I calculated it for the fun of it. The Lowes fan linked (7860 CFM and 24" blade) will only produce 13.5 lbs of thrust.

Here's the question for those interested.
Thrust = (Density) x (CFM^2) / ((Pi) x (r^2)) Remember to convert your units.

Density!

Water is Denser than Air.

Seal the Fan Motor is a empty 2L Pop Bottle, a good Ground Fault extension cord, It could make 25-30 knots.

 

[Old Ironmaker]

Whenever I am not having a good day I know I can always come aboard here and a smile will come to my ugly mug, each and every time. Especially today, we lost a dear friend of over 35 years today to that ugly C word. He was the man that put a fishing rod in my hands and put my butt in his Sears car topper many, many years ago. Thanks for the smile all.