Rim Driven Coreless Thruster running at higher RPMs

thank you all right so since the last video I've gone and taken out all the coils and just put or left 12 of them in there and I've changed the wiring from a Delta configuration to a y configuration so I have three phases there with four coils each and they're all joined at the end there and then as you can see here I also have the hall effect sensors set up there on some of the brackets so they're all in the right place here and just bonded in into place with some epoxy and so what this does allows me to run um you know far fewer coils and I can put more power through them for the from the controller that I have and subsequently I can actually get the uh the whole rotor to turn at a much better speed with this setup and the other thing I've done was I've changed the blade angles now because I can fix them at certain angles I've added another 11 degrees to the angles there as you can see and the reason for that is when I did the calculations I discovered that the way I was calculating the thrust was wrong and it was basically off by almost a factor of two so the other thing I've discovered as well was the angle that I had on the blades for the speed that I was running this thing at and even the speed I'm running it at now was wrong and the angle of attack on the blades was pretty much zero for the speed it was running out and the uh oncoming airspeed so changing it up to 11 degrees it basically gives me about a 10 degree angle of attack on the blades now which is probably in the best L over D lift over drag angle for these blades at least you know it's better so they're generating or they will be generating a lot more thrust now for this angle so with this more coarse pitch setting now I believe that would still be able should be able to get about twice the performance of a regular propeller compared to this so just to go back through the numbers there Cessna 172 should get about 460 pounds of thrust and a 182 would be about 640 a serious um 310 horse would be about 850 pounds of thrust the Raptor was about a thousand pounds of thrust and this this Thruster should be able to put out about uh 800 pounds of thrust at 5 600 RPM so here's the power setup that I'm using right now I just have uh five 12 volt batteries hooked in series there and I'm running an MGM comp Pro um 12 kilowatt controller there and it's also running with the whole effect sensors and so that one the maximum power I'm getting out of it right now is only about five kilowatts and as you can see I've just got it all wired up there as you've seen before and I put a couple of streamers on there so we can see the airflow foreign as you can see because that rotor is so far out of round from how it was manufactured it's just not possible for me to balance this properly it's 50 000 out around and actually started out being almost two inches out around when I got it and that's the best I can do with it so unfortunately I've tried to actually measure the thrust off of this thing but because I can't balance it it won't sit evenly when it's running on the standard I built for it and so I can't get a nice smooth thrust measurement off of it but it should be putting out about eight pounds of thrust here at like 600 RPM and as you can see those blades that with the angle that I have on those blades here now it seems to be that they're stalling quite a bit at the low RPM takes a little while before they actually start to generate uh the thrust on there and once it gets going then you actually get some smooth flow coming off of there so given this configuration 600 RPM is about the best I can get and it's not bad really us for 12 coils and it's obviously not the most ideal configuration for this electric motor anyway but you can imagine if you basically had those 12 coils and had four sets of them so 48 coils in there you'd be able to put four times the amount of power in there but obviously with a better setup you'd be able to do even better than that and one of the things I wanted to mention too was that so many people on the last video said that I need to have an inner ring on this but if you think about it the tips of the blades they're running at half the speed of what they are on the outside and not only that if you look at the Blazer aluminum blades the amount of mass that's in just in the tip in like the top one inch of the blades is so negligible and running at half the speed the amount of force on those from centrifugal force is really not that much at all I actually did run the FEA on this a long time ago when I was designing this and those blades are not going to bend anywhere near where they would be deformed they will Flex definitely under the maximum thrust um but they won't stay deformed or anything like that so there's really no need to have an inner ring there most of the force that's on those blades gets pushed down to the mounting on the outer ring so anyway that's one of the comments I wanted to make about the uh about the configuration there and a lot of people had commented about how would it handle a bird strike and obviously you know this size one wouldn't handle it very well that's why you have two of them on your aircraft and you know if you end up losing both of them because you hit two birds at the same time and I guess what you do is what you know a good pilot does you just go and land in a Hudson so finally just to summarize I think given a good configuration for the electric motor set up the coils on this thing I think you could get it up to 5600 6000 RPM you could also put larger Wheels there that the rotors running on and you get those bearings to run slower right now it's eleven to one so they're running 11 times faster than the than the rotor is but given the right setup you could have this thing running at 6000 RPM and given that I think at 600 RPM it's probably putting out about eight pounds of thrust at 6000 RPM so 10 times the speed it should be putting out 100 times the thrust so that would be eight uh 800 pounds of thrust and if you had two of these on an aircraft that's 1600 pounds of thrust and I don't I don't know exactly what the power requirement would be for that right now um but I think it would be you know half of what the same requirement would be for having a propeller set up anyway Olivia was one last run and that's about all I have for now on this video I don't know if I'm going to be doing any more um enhancements to this I don't think there's anything else I can do on this prototype I'm interested to see what other people uh get involved with and if anybody starts to sort of run some simulations models are available again still um if people want it and I'll put my contact info uh in the description of this video as well and thanks very much for watching foreign thank you [Applause]

Channel: Peter Muller

Views: 73,331

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Id: pALhUy-Fqs0

Length: 9min 15sec (555 seconds)

Published: Sat May 06 2023