oh my god... I never thought I could find any resources about building wind tunnels, let alone a high production, hq video like this one! Thanks a lot.
Thanks! I’m glad it was helpful. Part 2 is out as well. I was working on part 3 when the world went into the crapper. I will get back to it as soon as I can.
Wow! So cool!!! This is the best homemade wind tunnel I’ve ever seen. Looking forward to your smoke system. I am a Chinese bridge designer working on aerodynamic characteristics of bridge sections. I also wanna make a wind tunnel and your video helps me a lot. 谢谢！
I'm studying mechatronics and avionics; the mechanical aspects and the way they interact with our environment, this is what I am truly interested in. I have been taking ground and air courses as well, thank you.
@@DefiantWings I believe it! Fortunately for mine it's mostly for dynamic load testing of drone power systems, so I don't particularly need a smoke system. Curious what approach you're taking. I'm considering adding one. I've got some buddies who are super into vaping, and I think we can use a vape system and copper tubing to create the smoke points without disturbing the air too much. My biggest struggle right now is trying to figure out how to mount the load cell and motors without disrupting the air flow. I already have the logging system built and I've been using it for about 3 years now, so that part is no problem. Figuring out how to mount it though :O I need be able to consistently control the angle of attack as well, so it needs to be able to rotate the motor/prop assembly in relation to the air stream at specific repeatable angles. I have a few ideas. I'm thinking of using a vertical bar wrapped in a teardrop airfoil to prevent turbulence, and housing the load cell inside the tear drop. I can use a steel bar mount coming directly out from a slot in the airfoil. Then the bar inside the airfoil can rotate while the airfoil says consistently pointed into the airstream. I can probably 3D print the airfoil easily enough. This is a fun build. I'm looking to achieve air speeds of about 40m/s and I'll be using 4 miniquad motors in custom ducts for the powerplant, software speed control via UART. The whole system should be able to be completely automated. I'm hoping to use a high torque stepper motor to drive the rotation sequence as well to achieve the fixed angles.
I know this is a long time since you uploaded this video but this is very useful for my current thesis haha.... Just wanted to ask were you able to measure what your avg wind speed is in this windtunnel that you could achieve to test your wing profiles and aerofoil profiles? @DefiantWings
Where did u get all the calculation from? Can I get the reference material from where you got the numbers for the dimensions from? How do I calculate how much wind speed I can achieve through different cross sectional area?
I’m glad you liked it. I just used a 12v car radiator fan I found on Amazon. It’s no longer available but there should be others. What I found was that it didn’t supply a high flow rate or velocity when used in the tunnel. I think the highest speed I was able to get was 13mph. Fast enough for what I needed but I may upgrade to get more speed.
Hi, Good video however I don't understand, you said you will use a contraction ratio of 6:1. The area of the testing chamber is 12in and the inlet area of the contraction cone 30in and not 12*6=72 inch square. Maybe my understanding is wrong, so can you explain it to me ? Thanks
Hey Shawn, Saw you in the After hours Podcast. Would you mind testing some KFM airfoils? That would really help the community because we have no scientific data on KFMs at low Reynolds numbers. Fortis did some research but even his RE were way too high. Simulation programs can't handle the KFM because you need a precise transition model but that does not exist (as far I know). Please have a look at the KFM Threads on RCGroups. Cheers (from Germany) Nik
@@DefiantWings Thanks for the reply! I'm building a similar small-scale tunnel and my one concern is that the screen would unnecessarily decrease the velocity of the air entering the test section. However, the screen saves a lot of time and money over using spray adhesive to fix all the straws in place.
hey, I am looking to do this as a part of my master thesis, can you please name sources you used for determining geometry of a tunnel for best flow and speeds?
www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel This is one of the documents that I used and the only one that I still have a link to. Its a pretty good writeup and should help you with the sizing. I am planning to spend some time on the wind tunnel this winter to try to develop an instrumentation package. I'm also looking at a higher capacity fan as well. Too may projects, so little time
Hey, is it possible for you to share the paperwork that you used to study the wind tunnel? We (my project members) tried getting our hands on it but couldn't find any so little help would be appreciated 😅
Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel
I’m honestly afraid to add it all up haha. If I had to guess, I think I have about $600-$800 into it now. I have been doing a little bit at a time for a while so it doesn’t feel bad but I know it all adds up.
I have been considering a similar tunnel, do you know of any basic guidelines for fan size and power for a given chamber cross section and flow speed? I was thinking of sculpting a plug mold of the contraction zone out of something like clay (with some hollow filler in the center to reduce amount of clay) or carving it from blocks of wood, (finished with some non porous coatings and mold release) then covering it in fiberglass for a nice seamless smooth shape. I would also fillet all the corners (maybe 2 inch radius) so the duct cross section is not a sharp cornered rectangle, to reduce interference drag and flow issues; this filleting applies to all sections including test chamber.
Annnd I've read that honeycomb is good for reducing lateral turbulence but screens are needed for longitudinal turbulence. (not sure what how they defined this, I'm assuming small pressure pulses are longitudinal turbulence) Something like window bug screen. This may be useful in the diffuser just before the fan. The primary paper I was reading was about closed loop tunnels so there were two corners and 3-4 diffusers between the test chamber and fan, so they used screens between the honeycomb and the contraction zone.(as I recall it was screen of 0.5mm wires and 80% holes by total area)
@@mytech6779 Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel I have window screen on either side of the straws/tubes. They help with the turbulence and hold the straws in place. win-win
Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel There is a lot of great information in here. You really want to start dimensioning the test chamber first based on the size of you test vehicle. All if the other components are based on the size of the test chamber. The document linked above has a lot of great info on the sizes
The dimensions discussion is at 6:06 But the test chamber is 12”x12”x24”. The defuser is 12”x12” tapering to 16”x16” and is 38” long. The inlet is 30”x30” and tapers down to 12”x12” and it 42” long
The authors have two wrong scientific approaches: researching the creation of Lift force and Low pressure at upper side of the wing, relative to the ground surface and Earth. I explain the aerodynamic cavitation and existence of Lee side aerocavern, and creation of Aerodynamic force.
this guy has just saved me hours of work
Well if you sat through the whole thing then you deserve a few hours break 🤣🤣. I’m glad I could help save you some time 👍
oh my god... I never thought I could find any resources about building wind tunnels, let alone a high production, hq video like this one! Thanks a lot.
Thanks! I’m glad it was helpful. Part 2 is out as well. I was working on part 3 when the world went into the crapper. I will get back to it as soon as I can.
Wow! So cool!!! This is the best homemade wind tunnel I’ve ever seen. Looking forward to your smoke system. I am a Chinese bridge designer working on aerodynamic characteristics of bridge sections. I also wanna make a wind tunnel and your video helps me a lot. 谢谢！
吴斐 thank you! There are some links in the comments below that might help you. I hope to get part 2 done later this fall
I'm studying mechatronics and avionics; the mechanical aspects and the way they interact with our environment, this is what I am truly interested in. I have been taking ground and air courses as well, thank you.
Cant wait for part 2. Great video. Definitely one of the best wind tunnels on YT.
Thank you! I am hoping to get back to this project this winter and get the second video pulled together.
Nice video. Looking forward to Part 2.
revgro thx!
Fantastic video, looking forward to part 2
Thank you. I will try to get part 2 done later this fall once flying season winds down
This is exactly what I was looking for, thank you!
dernodar glad it helped
Awesome video. Looking forward to what you find out with it.
Thx man! Yeah, I'm looking forward to that as well. I;m working through the hard part with the smoke and lighting now. Getting closer
That looks incredible! Really helped me out and I can’t wait till part 2!
Jarrod Ladd I glad that it helped you out. I hope to get back to the project and video this winter when I have more time
@@DefiantWings Looking forward to part 2 as well! I'm working on a similar project!
QuadMcFly the smoke system and lighting is proving to be more complex and problematic than the actual build.
@@DefiantWings I believe it! Fortunately for mine it's mostly for dynamic load testing of drone power systems, so I don't particularly need a smoke system. Curious what approach you're taking. I'm considering adding one. I've got some buddies who are super into vaping, and I think we can use a vape system and copper tubing to create the smoke points without disturbing the air too much.
My biggest struggle right now is trying to figure out how to mount the load cell and motors without disrupting the air flow. I already have the logging system built and I've been using it for about 3 years now, so that part is no problem. Figuring out how to mount it though :O I need be able to consistently control the angle of attack as well, so it needs to be able to rotate the motor/prop assembly in relation to the air stream at specific repeatable angles. I have a few ideas. I'm thinking of using a vertical bar wrapped in a teardrop airfoil to prevent turbulence, and housing the load cell inside the tear drop. I can use a steel bar mount coming directly out from a slot in the airfoil. Then the bar inside the airfoil can rotate while the airfoil says consistently pointed into the airstream. I can probably 3D print the airfoil easily enough.
This is a fun build. I'm looking to achieve air speeds of about 40m/s and I'll be using 4 miniquad motors in custom ducts for the powerplant, software speed control via UART. The whole system should be able to be completely automated. I'm hoping to use a high torque stepper motor to drive the rotation sequence as well to achieve the fixed angles.
Love it. Looking forward to part 2. Love to see some smoke ;)
The structure was the easy part. The smoke and lighting have proven to be the real challenge.
Excellent video and awesome looking wind tunnel!
Jeremy H thanks man! Still a work in progress
This is EXACTLY what I wanted! Thanks! I’m building one too
Great! I’m glad the video helped. It’s a lot of fun but I wish I had more time to spend with it
Good job on the building. looks like the rite way to do this.
Thx man! Hoping to get some good data from this.
Amazing!!!!! Great Ingenuity!!!
Great video, could you tell me, what kind of smoke generator is? thanks
Theefun 400-Watt Portable... www.amazon.com/dp/B01MDNTD7A?ref=ppx_pop_mob_ap_share
Amazing videos!! Thanks for all your hard work!
Thanks!
Very useful, thanks for sharing it! i'm going to build one too!
Thx! Glad you found it useful
Nice work..when you're going to upload part 2?
onkar salavi thank you! Part to is in the works now. There will likely be a bart 3 well
Thanks! Ib physics is a pain
I know this is a long time since you uploaded this video but this is very useful for my current thesis haha.... Just wanted to ask were you able to measure what your avg wind speed is in this windtunnel that you could achieve to test your wing profiles and aerofoil profiles? @DefiantWings
I was only able to get about 15-20mph with the fan I used. It needed a more powerful blower.
Where did u get all the calculation from?
Can I get the reference material from where you got the numbers for the dimensions from? How do I calculate how much wind speed I can achieve through different cross sectional area?
My dad built a wind tunnel for his high school science fair. He would have won, but...
It exceeded the maximum size requirement.
They get big fast. There is an awful lot tunnel for a little bit of test chamber...🤷♂️physics 🤣
Cool wind tunnel build, learned a lot from this!! Which fan did you use?
I’m glad you liked it. I just used a 12v car radiator fan I found on Amazon. It’s no longer available but there should be others. What I found was that it didn’t supply a high flow rate or velocity when used in the tunnel. I think the highest speed I was able to get was 13mph. Fast enough for what I needed but I may upgrade to get more speed.
Hi,
Good video however I don't understand, you said you will use a contraction ratio of 6:1. The area of the testing chamber is 12in and the inlet area of the contraction cone 30in and not 12*6=72 inch square. Maybe my understanding is wrong, so can you explain it to me ?
Thanks
It’s a 6:1 contraction in area. 12”x12”=144sqin x 6 = 864sqin. I used 30”x30” for the inlet wick gave me 900sqin.
@@DefiantWings oh, yes understood thanks for answering so quickly !
dude, thank you so much.
Hey Shawn,
Saw you in the After hours Podcast.
Would you mind testing some KFM airfoils? That would really help the community because we have no scientific data on KFMs at low Reynolds numbers. Fortis did some research but even his RE were way too high.
Simulation programs can't handle the KFM because you need a precise transition model but that does not exist (as far I know).
Please have a look at the KFM Threads on RCGroups.
Cheers (from Germany)
Nik
I’m sure we could make that happen. I need to get it finished up this winter and then we can talk further
if you can steam a room and let the wood lie there for a while, it'll be more malleable and conform to desired shapes well.
i dont understand anything, but it looks awesome!
As long as it looks cool😎😜
@@DefiantWings yes, that is important lol
can you build a PC with out fans inside a wind tunnel and have the wind cool it?
I have absolutely no idea 🤷♂️
Very cool work, possible pdf file design with measurements
How where the straws fixed in place? If they aren't glued won't they just get blow out by the fan?
The straws are stacked between pieces of screen. It holds them in place and helps cut the turbulence as well
@@DefiantWings What type of screen? A common exterior window screen?
Yep, it’s some fiberglass screen I had left over from a screen door repair. Nothing fancy 🤣
@@DefiantWings Thanks for the reply! I'm building a similar small-scale tunnel and my one concern is that the screen would unnecessarily decrease the velocity of the air entering the test section. However, the screen saves a lot of time and money over using spray adhesive to fix all the straws in place.
It was a compromise I was willing to make. A lot of the research I read said that screens were a part of the flow straitening process anyway.
hey, I am looking to do this as a part of my master thesis, can you please name sources you used for determining geometry of a tunnel for best flow and speeds?
www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel
This is one of the documents that I used and the only one that I still have a link to. Its a pretty good writeup and should help you with the sizing. I am planning to spend some time on the wind tunnel this winter to try to develop an instrumentation package. I'm also looking at a higher capacity fan as well. Too may projects, so little time
@@DefiantWings thank you very much, finally a piece of literature that describes exact geometry after all the books I downloaded
v-e-l-o-c-i-t-y
Hey, is it possible for you to share the paperwork that you used to study the wind tunnel?
We (my project members) tried getting our hands on it but couldn't find any so little help would be appreciated 😅
Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel
When is part 2 coming?
Probably not until later this fall. I have been so busy with wing development that I haven’t had a chance to finish the build video
how much would this all cost roughly?
I’m honestly afraid to add it all up haha. If I had to guess, I think I have about $600-$800 into it now. I have been doing a little bit at a time for a while so it doesn’t feel bad but I know it all adds up.
I have been considering a similar tunnel, do you know of any basic guidelines for fan size and power for a given chamber cross section and flow speed?
I was thinking of sculpting a plug mold of the contraction zone out of something like clay (with some hollow filler in the center to reduce amount of clay) or carving it from blocks of wood, (finished with some non porous coatings and mold release) then covering it in fiberglass for a nice seamless smooth shape.
I would also fillet all the corners (maybe 2 inch radius) so the duct cross section is not a sharp cornered rectangle, to reduce interference drag and flow issues; this filleting applies to all sections including test chamber.
Annnd I've read that honeycomb is good for reducing lateral turbulence but screens are needed for longitudinal turbulence. (not sure what how they defined this, I'm assuming small pressure pulses are longitudinal turbulence) Something like window bug screen. This may be useful in the diffuser just before the fan.
The primary paper I was reading was about closed loop tunnels so there were two corners and 3-4 diffusers between the test chamber and fan, so they used screens between the honeycomb and the contraction zone.(as I recall it was screen of 0.5mm wires and 80% holes by total area)
@@mytech6779
Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel
I have window screen on either side of the straws/tubes. They help with the turbulence and hold the straws in place. win-win
How’s it turning out?
MCRideout not bad. I’m working on part 2 now. Hope to have it ready in a couple of weeks.
I wanna build one could u possibly help me with the dimension I do rc speed runs with 5th scale cars
Here is a link to one of the documents that I used. I found it very helpful. www.intechopen.com/books/wind-tunnel-designs-and-their-diverse-engineering-applications/design-methodology-for-a-quick-and-low-cost-wind-tunnel
There is a lot of great information in here. You really want to start dimensioning the test chamber first based on the size of you test vehicle. All if the other components are based on the size of the test chamber. The document linked above has a lot of great info on the sizes
Can u tell me again what is the dimensions ?
The dimensions discussion is at 6:06
But the test chamber is 12”x12”x24”. The defuser is 12”x12” tapering to 16”x16” and is 38” long. The inlet is 30”x30” and tapers down to 12”x12” and it 42” long
I would have just made the whole thing out of Home Depot foam board and 3D printed the mesh, door, etc. Great videos nonetheless!
The authors have two wrong scientific approaches: researching the creation of Lift force and Low pressure at upper side of the wing, relative to the ground surface and Earth. I explain the aerodynamic cavitation and existence of Lee side aerocavern, and creation of Aerodynamic force.
Wait i have an exam tomorrow, what am i doing here?
Why put this horrible music to loud you cant hear any think