Coanda Effect Hovercraft

I'm sure many of you watching are familiar with how hovercrafts work they force air down underneath the fuselage creating a pocket of high-pressure air that they can float around on and this allows them to slide over various different surfaces but I'm also sure that many of you are wondering one earth is a condor effective of craft the Coanda effect is the tendency for a fluid to flow around the outside of a curved surface and I explored this Condor effect in a previous video he's a short explanation of how the Coanda effect works when air or any other fluid exits a nozzle at high velocity it will pull surrounding molecules with it as it disperses into the stationary surrounding air but when a surface is placed near to the flow the air between the surface and the fast flow is dragged along with it this causes the low-pressure zone between the fast-moving air and the surface and the surrounding atmospheric air above it will push down on the flow attaching it to the curved surface if you haven't seen my previous Condor effect video I used the Condor effect to redirect airflow around a dome to produce lift for a drone in the end I found it to be terribly inefficient however I did notice a very strong ground effect acting on the drone and said the following it would be interesting to see if this could be modified into almost like a ground effect hovercraft her a condor effect ground effect hovercraft and also see whether that still requires gyros for stabilization as hovercrafts don't require active stabilization they just sit on a cushion of air above the ground so here is a very basic cross section of a hovercraft there is a fan up top which blows air down underneath alpha craft and creates a pocket of high-pressure air lifting the hovercraft off the ground now my plan is to redirect this downwards airflow to do a 90 degree turn and flow out horizontally above the hovercraft then using the Condor effect the air will flow around the curved surface and produce lift not only will the downwards moving air produce lift but also the fast-moving air above the hovercraft curved surface will be at a lower pressure than the stationary air below the hovercraft therefore producing lifts similar to an aircraft wing also my second theory which may or may not be correct is to curve the surfaces through a full 180 degrees in the hope that a small portion of the air flow will flow under the hovercraft and pressurize the underside of the fuselage therefore creating a greater pressure difference between the top and the bottom and producing more lift so here is their design to mainly fans and mounted just 3d printed brackets which attach to an aluminium frame under the fuselage this will keep them aligned and prevent any propeller collisions as I plan to build the red curved sections from foam board this aluminium frame also acts as a strong mount for attaching the rear thrusters high up and out of the Condor effect zone I haven't worked with foam board for a while and this is probably one of the most complex shaped I'll produce a date so in order to get the angled sections correct I use the sheet metal tool in fusion 360 to make a template which can be printed and used to trace parts onto the foam board each section was then covered in packing tape to make the surface smooth and also add some strength to the foam board as well as adding some color now because producing this curved shaped fuselage from sheet foam became repetitive very quickly I kept entertained by listening to an audio book called how to build a car by Adrian Newey via audible who are the sponsor for this project it touches on many engineering fields but I found the aerodynamic development of a Formula One car really interesting an example was a decision whether to move the regulation nose cameras due to a trend of other teams doing so but data from the computational fluid dynamics software conflicted with the data from the Windtunnel tests so they chose to run the test at the next race one of the drivers didn't like the new mounting position and the other was non-committal but the data showed that the new assembly was slightly up in overall Aero load this is really relatable to me as when I build such projects for YouTube I always like to test things before coming to a conclusion audible content includes an unmatched selection of audio books an original audio shows you can listen to audible on the go whilst doing CAD work or tinkering on your latest project and if you want to sign up go to audible.com forward slash Tom Stanton or if you're in North America text Tom Stanton - 500 500 and start listening with an exclusive 30-day free trial one free audio book of your choice and - audible originals absolutely free so thanks to audible for sponsoring this project and it's time to fire up the CNC [Music] [Applause] the aluminium parts will cut from two millimeter sheet aluminium and in total weight about 163 grams once the top plate of foam was attached to the curve sections the aluminium frame can be clamped to the foam board using two 3d printed rings I then initially attached the motors directly to the aluminium frame as I wanted to test whether impellers would be enough to lift his craft but the motors just weren't strong enough to drive them and became very hot at just 50% throttle as each impeller took about nine and a half hours to print plus weighing in at just under a hundred grams each I moved on quickly to using conventional propellers which actually seemed very promising [Music] [Music] [Music] [Music] once the rear motors were attached and soldered up I programmed my transmitter to control all four motors and it was ready for a test okay here's the first test of the Coanda effect hovercraft just going to spin up the main lift motors to see if lift off the ground a bit [Music] definitely has enough thrust that's about 50% throttle it starts to lift off [Music] let's see if we can get it moving forwards just got to get the right throttle control so it doesn't take off but enough to reduce the friction so let's try that that works [Music] [Music] I'm surprised it's working so well on grass he's a carefully tuned how much for us the main motors are producing citizen want to take off too much just about there seems pretty good yeah it's very top-heavy rice it was now the following day and I'm going to give this commander affect hovercraft another test I made a small modification to the motor mounts at the rear they actually have a small well it's a 15 degree downwards thrust angle now I know just looking back at the footage from yesterday that when I increase the thrust at the rear it seems to want to push the nose down quite hard so I'm hoping that this sort of downwards thrust angle will go slightly more through the center of mass and sort of push the rear down a bit more so I'm now the sun's coming out let's give it a test [Music] [Music] so it seems like the nose pitching down issue has reduced and I can pick up a bit more speed the flipping over issue is a I think unresolvable apart from my lack of piloting skills just to give you an idea of the co and effect actually working I'm going to throttle up the rear motors without the front ones okay that does actually move it on this a soft grass but if I thought to them up so it's not moving so it's just about to move about there now if I throttle up the lift motors and keep the rear ones constant it reduces the friction another goes you see how fast we can get it going towards me this could end badly she tried to take off I wonder if it will take off if I go fast enough [Music] one interesting thing I've just noticed is that it seems to be collecting all the leaves on the inside so I wonder if that's the Condor effect blowing air all the way run the surface and then filling this with high-pressure air which is also picking up lots of debris on the floor I I've covered all the electronics in packing tape so that should be waterproof because it's quite wet on the grass this morning so many leaves are there [Applause] [Applause] [Music] [Applause] [Music] so there we have it a condor effect hovercraft is it going to be replacing conventional hovercrafts any time soon I highly doubt it does it have any advantages over a conventional hovercraft well aside from collecting leaves not really I really enjoyed this project and I'm really happy that the commander effect actually worked to lift this thing off the ground sometimes a bit too much but I hope you found this project interesting if you did enjoy this video then it'd be great if you can leave a thumbs up down below and if you're new to my channel and want to see other crazy projects similar to this it would be great if you could click to subscribe down below and a massive thank you to all of my supporters over on patreon comm for supporting my projects and these videos and making things like this possible so thanks once again for your support thanks once again for watching and see the next video roll the outtakes [Music] [Applause] [Music]

Channel: Tom Stanton

Views: 820,926

Rating: 4.8948073 out of 5

Keywords: hovercraft, Coanda effect, coanda, Coandă effect, drone, Propulsion, thrust, lift, fluid dynamics, DIY, homemade, aircraft, engineer, engineering, science, physics, how does the coanda effect work, Henri Coanda, VTOL, Experiment, Coandă effect explained, ground effect, downwash effect, aerodynamics

Id: ebqQxLwjWfY

Length: 16min 36sec (996 seconds)

Published: Fri Oct 11 2019