So who here has tried to make a homemade wind tunnel to test wings? My first attempt.

[yamahasho]

Hello all, I had an 18” by 13 centrifugal fan around around and wanted to see if I can push some real air to make a wind tunnel.

Looks like this:

https://surpluscityliquidators.com/prod ... motor.html



Trust me this thing is heavy and pretty big but is it big enough? I think I need at least two.

Spec picture Shown here page 107

https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

18-13a, so 18 diameter with 13 width of the fan, and 18”x13” outlet.

Shown here
https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

Page 111, Fgp-18-13A
At .375” static pressure and 723 rpm it needs 3.14Hp, has a flow rate of 6200Cfm. (Not that much)

I plan to run at 2000 rpm but probably need some real Hp, your guess is as good as mine. Fan graph only goes to .375”.

My question before I make the contraction and chamber is how much Hp is needed? Anyone able to make something like this at home and what motor size did you use? How much wind speed did you achieve?

I would greatly appreciate if someone could share their experiences or critique this project.

[Andres125sx]

Sorry, can´t add anything valuable, apart from my support. I love this project, keep us updated and good luck

[Greg Locock]

Each doubling of speed seems to need 10x the power, and i'm not convinced that you can blithely push an 800 rpm device to 2000 rpm

[J.A.W.]

@ OP, you might want to 'do the mathematics' before actually buying the hardware...

Why a wind tunnel anyhow? What kind of test results are you looking for?

Can't you test a wing on a model plane in open air? Or on a surface vehicle?

A large gas-pressure tank & air compressor might well blow a stream down a test tube, too.

[yamahasho]

Each doubling of speed seems to need 10x the power, and i'm not convinced that you can blithely push an 800 rpm device to 2000 rpm

So you’re thinking about 30Hp to get this fan up to 2000Rpm, we’ll I better go start looking how to get that, may need a gas motor for this one versus running on a 3-phase motor at 240v. A 30Hp electric motor would be enormous.

Thanks for the input.

[yamahasho]

@ OP, you might want to 'do the mathematics' before actually buying the hardware...

Why a wind tunnel anyhow? What kind of test results are you looking for?

Can't you test a wing on a model plane in open air? Or on a surface vehicle?

A large gas-pressure tank & air compressor might well blow a stream down a test tube, too.

My first idea was to get about 12 leaf blowers but I knew that wouldn’t cut it.

We’re testing downforce on my car’s wings and other winglets in various places.

I haven’t thought of the instrumentation yet but it would have to be precise since the winglets would have to be scaled down.

An air compressor tank you say? Wonder how large it would have to be for a test chamber of around 16” by 16”.

[TNTHead]

Hello all, I had an 18” by 13 centrifugal fan around around and wanted to see if I can push some real air to make a wind tunnel.

Looks like this:

https://surpluscityliquidators.com/prod ... motor.html

https://asp-scl-web-3-pavinthewaysoftw ... 192622.jpg

Trust me this thing is heavy and pretty big but is it big enough? I think I need at least two.

Spec picture Shown here page 107

https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

18-13a, so 18 diameter with 13 width of the fan, and 18”x13” outlet.

Shown here
https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

Page 111, Fgp-18-13A
At .375” static pressure and 723 rpm it needs 3.14Hp, has a flow rate of 6200Cfm. (Not that much)

I plan to run at 2000 rpm but probably need some real Hp, your guess is as good as mine. Fan graph only goes to .375”.

My question before I make the contraction and chamber is how much Hp is needed? Anyone able to make something like this at home and what motor size did you use? How much wind speed did you achieve?

I would greatly appreciate if someone could share their experiences or critique this project.

Interesting idea.
How are you are going to stabilise the flow? For a wind tunnel the turbulence intensity needs to be low enough otherwise you cannot get any sensible data out of it.

[yamahasho]

Hello all, I had an 18” by 13 centrifugal fan around around and wanted to see if I can push some real air to make a wind tunnel.

Looks like this:

https://surpluscityliquidators.com/prod ... motor.html

https://asp-scl-web-3-pavinthewaysoftw ... 192622.jpg

Trust me this thing is heavy and pretty big but is it big enough? I think I need at least two.

Spec picture Shown here page 107

https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

18-13a, so 18 diameter with 13 width of the fan, and 18”x13” outlet.

Shown here
https://www.lauparts.com/-/media/lau-pa ... 062020.pdf

Page 111, Fgp-18-13A
At .375” static pressure and 723 rpm it needs 3.14Hp, has a flow rate of 6200Cfm. (Not that much)

I plan to run at 2000 rpm but probably need some real Hp, your guess is as good as mine. Fan graph only goes to .375”.

My question before I make the contraction and chamber is how much Hp is needed? Anyone able to make something like this at home and what motor size did you use? How much wind speed did you achieve?

I would greatly appreciate if someone could share their experiences or critique this project.

Interesting idea.
How are you are going to stabilise the flow? For a wind tunnel the turbulence intensity needs to be low enough otherwise you cannot get any sensible data out of it.

For the honeycomb I was thinking straws, that’s a bit down the road yet. Open to easier less labor intensive ideas.

I have all the hardware already except the motors, I have 12hp electric motor but looks like it’s not enough power to get the speed I’m looking for.

[hollus]

viewtopic.php?t=14495

Just in case you can borrow sone ideas from there

[yamahasho]

viewtopic.php?t=14495

Just in case you can borrow sone ideas from there

As always good find.

[Big Tea]

Don't know enough really, but could you test a wing by spinning it on a pole with strain gauges affixed?

A longer pole means more speed.

[yamahasho]

Don't know enough really, but could you test a wing by spinning it on a pole with strain gauges affixed?

A longer pole means more speed.

You’re on the right track most of the YouTube video people put the wing on vertical sliders with a calibrated spring on them using F=kx formula, crude.

For drag they would place the apparatus on sliders as well but horizontally.

[Greg Locock]

For our second solar car we mounted a flat board on a roof rack, installed a 1:5 scale model carved from wood, and ran pressure tappings all down the centreline of the model. Then drive the car at 60 mph. Pitch angle has to be adjustable.

[yamahasho]

[rgava]

Here: https://www.frh.utn.edu.ar/media/empres ... ytunel.pdf you can see Tunnel number 2 is quite similar to what you are thinking.
It's in Spanish, but you can do a decent automated translation.
I was involved in the construction of that tunnel some 30 years ago...

It has a 3 DoF scale to measure lift, drag and moment