So First off... love the site and LOVE my Plans, already have built the f-22, as a pusher, but, as I was building this plane, I was wondering about using my "WeMoTec" MD001-5 90mm Midi Ducted fan.. Powered by a Jedi Phazor 15/4, 30amp Esc and a 20C, 11.1, 1250Mah 3 cell Lipo battery... which turn's an astounding 22,000+ RPM's
Maybe WAY to much power.. but I like it like that, or maybe just right?? we will soon see as my manic state increases... Buahahaha seriously now...
I've purchased the T-50 V2, the F-35 V2 and the F-22 V1 (wish I had bought the V2)
As I consider the three planes, and the 90mm size fan, the T-50's fuse is just not right, to hide away the fan, the F-22 has perfect frontal ducting but, would stick up through the wing about an inch(Probably OK) however the Aft ducting is what concerns me, it's wide and square and only tapers bottom to the wing (if enclosed) same for the F-35.
The Fan Manufacturer, suggests to Taper the Aft ducting down to "MAYBE" increase Thrust and Efflux Velocity.
They suggest it to be 60 to 80mm long and reduce down to 75mm and of course they mean it to be Round, not square... But DOES it REALLY MATTER????
The F-35 seems to be the best choose for the project, the upper Fuse can be enclosed and tapered easy enough, but then there's the bottom Squareness issue, again is it really that big a deal???
Please I'm seriously over thinking this I believe, come on Pro's Help me out
Quote 0 0
A thrust tube really does add more thrust. It cleans up the air flow into a cylinder shape rather than just a splash of air coming from the unit. A few people have done the f35 edf with a 70mm fan but I've yet to see any if these planes with a 90mm. I haven't used any edf bigger than 64mm but the 90mm setup may just be to big. And it's also best to have some fan above the wing so that clean air is always going through. Many others can provide better help than I though on this topic
Quote 0 0
To fit a 90mmDucted Fan in the fuselage, you would not have to scale up the F-35 V2 very much. To put it in a F-22 V1, you would need to scale it up and modify it quite a bit.

The F-22 V1 is the standard for most of the modern foamies, it was the first of its kind. With an "NTM Prop Drive Series 2836 2700kv" installed, its performance is off the chain. It has 39 ounces of thrust with plenty of power and speed. It would blow away a 90mmDucted Fan in the F-35 V2. For ether one, you will need a large flying area.

These blue short cuts go to some good information resources:
The Scratchbuilders Beginner's Guide
The walk through of a build.
Resources Post 1 has short cuts to other helpful threads
An EDF thrust tube Here, you will find the hows and whys of the thrust tube. It's easy to make a light thrust tube out of Mylar (a thin sheet of plastic) that will fit inside the fuselage.
Model: NTM Prop Drive Series 2836 2700kv
Kv: 2700rpm/v
Motor Wind: 6T
Max current: 50A
Max Power: 520W @ 11.1/V (3S) / 595W @ 15v (4S)
Weight: 87g
ESC: 40~60A

Prop Test Data:
4.75x4.75 - 11.1V / 311W / 28A / 0.7kg thrust
4.75x4.75 - 14.8V / 594W /40A / 1.12kg thrust
5x5 - 11.1V / 400W / 36A / 0.85kg thrust
6x4 - 11.1V / 520W / 46.8A / 1.2kg thrust
Quote 0 0
How are you going to get any power from a 90mm fan run by a 30A ESC and a battery that's only capable of 25A? Assuming your motor is appropriately sized, you're going to need to get a MUCH larger ESC and battery, and maybe even a 4S to get the power you're hoping for. Additionally, our 2200kv motors already push more than 22,000rpm on a 6x4 prop. For an EDF, you're going to want something in the 30,000-40,000rpm range.

For the plans at 100% scale, though, a 70mm EDF is about the biggest you can get into the fuselage without having to either scale up or allow the EDF to stick through.
Yes, I've known that I'm "different" for some time now...
Quote 0 0