Recent Attachments for winmodels
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WM400 with Medusa motr in my test stand (after the measurements)
Graph of the MEDUSA Power Analyser PRO
the cables will be hidden under a plastic sheeting
One can see the narrowest part of the duct is around where the cables cross it. This cross section should be about the same as the fan annulus!
Have a look at the low rpm at the high power.
The thrust tube reduces to 95mm. There is the interior cone still missing which may improve the thrust a little bit. For the next measurements I will install a little air take off to cool the ESC.
The intake is a simple affair made from blue foam with a normal intake lip radius. One of the great advantages of direct motor installation is the near ideal cooling.
My trusty test rig has been stiffened to increase accuracy of the thrust measurement
one of my illustrations
The text on the graph explains all.
This graph shows the thrust decay over the speed range for a constant power. All fans behave like that in principle!
The latest development with the Neu 1915/1Y motor is still to be added, for all I have measured so far it's in the very top range.
The graph itself says it all
As one can see: for everyday use increasing the power by 50% does not increase the speed by a large margin. To fly fast it needs a very slippery airframe as well.
Anybody for a speed run? If a reducing nozzle is used the fitted one will be cut short at the tape and the nozzle fitted.
From the other side
Looking down the bell mouth
The long intake with pressure tappings is used to smooth the air flow and measure the flow rate
The air intake (one of two) simulated for test purpose.
The WM fan, which is a derivative mix of the 600 and 1000 and is powered by a Plettenberg special fan motor.
Lay out and ducting for el. ducted fan propulsion. There can be an intake BL suction removal system, as on the original, but it is doubtful that it will gain a lot.
the WM1000-110 fitted with a WM2000 rotor (only for the view)
Same from a differnt angle
the two WM1000 with Neu motor 1915 (which is even better than the ORK in my view, up to around 3.5kW
A WM600-95/A with a Plettenberg motor of up to around 2.8kW as shown above
The WM2000-125 nearest
WM600-90/A the first of the 90mm bunch and still with an alu motor support tube.
The first lot of WM fans with directly fitted stator arrangement (one exeption): two WM600-95, two (three) WM1000-110/A and one WM2000-125/A from left to right
Here are some WM fans for different customers, including special ducting, all ready to be tested
One can always dream - or what could be done if there was some interest. The losses in the contorted ducts are surprisingly low.
Installation drawing of the WM200-140/FF
I built two of those last year with "hundreds in the pipeline". After I supplied the second one I never heard anything from that guy again.
WM2000-140/FF full carbon "front fan" with Lehner 2250 motor. It produces 5kg of thrust with only 2300W input power according to measurements of the customer.
One can just see the directly fitted stator blades - no motor tube and excellent cooling.
This is the full carbon version of the WM600-95. 95mm is the maximum diam. of the fan. Principally you can have any shroud diameter, but I have only mandrels available for 75, 80, 90 and 95mm.
Looks a little ragged, but I still was trying to get up to max without actually busting anything. Maximum values: 4800gram thrust @ 27200rpm, 3850W el.power in = 3300W shaftpower, air exit vel. ~100m/s = 225mph
I will give it a good going over and try again soon.
This is the seven blade rotor, which was run up to full power (27200rpm). The rotor was actually made for the WM1000 for a max power of 3000W and slightly different stator blades.
Another picture of the exhaust nozzle
Rear view of the WM2000-110/A showing the business end with only 85mm diameter
The new nine blade rotor for the WM2000. It still needs some more balancing after it rubbed slightly at the fan housing
WM2000-110/A with bell mouth entry for static testing.
As one can see I used a servo tester for the throttle not the MEDUSA output, it didn't want to work with the controller in this case.
Test rig with MEDUSA installed and the WM2000-110/A ready for static thrust measurements
New Honda light Bizjet
that's about the gap between fan and shroud: 0.1mm, only used for alignment od the motor/stator assembly. The running gap will be about the same, after I have trimmed off another 2/10th static.
and here you see the difference: a much smaller annular area with the same motor: WM2000-110/A
the same again from the other side
WM2000-110/A in the jig for the placement of the fixing rails. I particularly like the reinforcement gussets
WM2000-125/A with Neu motor 2215/2Y this should be good for about 5000W at around 22-23k rpm
one has to imagine the exhaust of a jet engine striking the tail - but with a EDF it should not be a problem
intake duct for WM1000, there is also a carbon version, but a few carbon tows around it do the same job
Intake duct for ... and then he changed his mind...
intake duct for EF128
This one WM fan felt lonely, so it just came along for a group picture.
If you have only five blades life is easy (manufacturing wise) though the mould is rather "involved".
This shows the crux: overlapping blades at the hub. Unless you invest in a very expensive mould this can only be done with seperate blades.
This WM600-90 is starting to collect dust and needs some high speed fresh wind - to be tested at the next opportunity, soon I think.
Rotor of the WM2000. This is based on the design of the WM2000 rotor for the front fan version which I built last year. This design is good for up to about 28k rpm, though it will never do more than 23000 with the long blades.
-- and stacked to the right up one WM600-95. The latter is the largest size I can do in the 600 range: 95mm fan diameter.
This is the current rotor for the WM1000, it weighs around 58g, but it's still not quite right from a production point of view.
mainhousing with installed motor and stator arrangement; on the left are 2 WM2000 followed to the right by 2 WM1000
Just for you to guess :-)
Another view of the WM2000 stator and main housing.
Stator assembly in the main housing. The housing weighs only 48gr.
Finished sized stator assembly of the WM2000. The blades still need some reworking. The rotor hub with one blade is just stuck on for the eye.
This is a WM1000 stator assembly. The weight comes from the motor (around 410gr) Neu 1915.
Sizing of the stator assembly to an accuracy of about 2/100th of one millimeter!
Some parts to make up two prototypes. The second one is for wind tunnel experiments.
These are the final dimensions for the WM200-125. Later it may be available with an even larger diameter if there is demand. As is a very powerful package!
Let the figures speak for themselves
The next motor is already lined up. The WM2000 can be made up to 150mm diameter.
The WM2000 stator
What about this then?
New (very old) blade retainment for the WM1000 rotor. The one piece moulding has so far evaded me.
WM fans in various stages
master models for WM2000-X/A blades. The motor is a Neu 2212 with up to 5000W output.
as in other photos here in the thread the characteristic dimples at the front gives it away: GWS 55 EDF rotor
....after the take off speed is hardly reached it goes downhill with the thrust :-). This is a totally normal behaviour for ALL fans, though may be different in grade.
The graph in question with mental lines added (in mauve)
Another view of the test rig with the two WM400 test candidates. The Kontronik Fun480-2800 is another motor to be tried.
My test rig with the Medusa data aquisition system will take the strain out of the testing (still the wiring up to do and the all important calibration)
In this WM400 now works a MEGA 16/25/3. I have now made a front entry fairing, which hopefully let me gain a few more %-points.
Here the Medusa BL motor with a very KV of only 900rpm/V is installed in the WM400. Lets see how it goes on a 10s LiPo
Plane at rest. See how the air is sucked into the intake from all sides, which calls for nicely rounded intake lips.
The purple line shows the total energy of the air flow, which can only be increased by the fan. Where friction drag is encountered enrgy is lost.
Latest approximate dimensions of WM400. The fan diameter is 70mm.
this is the other position from the system output to the ESC. All very nicely thought out and realized.
I will fit the rpm sensor into the cone and a refector on the rotor.
this is just the real time screen. I still have to play with graphs
a servo attached instead of the ESC, so one can actually see that there is some output from the system
A nice new toy - my Christmas present
Tern performance 500W.pdf
just about visible: the air gap between motor and housing
they managed to reduce the blade gap considerably, but before I have the shaft adapter I can not balance the rotor and see how it is allround
all four screws used and added some air passages - hope it helps
for the tests I made a straight intake with a normal intake lip. The cone in front will be used in future tests to fair the motor front, which up to now has been just the motor squared off.
the WM400 will be available with the proper thrust exit nozzle for all "normal" applications (55mm exit)
the WM400 in my test stand
this is the power-thrust curve derived from the measured values
Seen as an individual transition piece you wouldn't form that (nice looking) flat on the side?
Two explanations: the duct diameters are in mm and the horizontal scale is logarithmic, hence the strange numbers.
This is the other layout for the duct. There are several features which make it easier to manufacture; but is it worth it?
Statorblades fitted directly to the motor housing. The extension ring is clearly to be seen. A longer motor is in the offing.
Comp. WM600 with 80mm and 90mm fan diameter.
I'l be happy when I'm through this lot.
Rotor and stator for Eric's WM1000. The main housings are now getting a lot better, with a nicely smooth and shiny surface on the outside as well.
Putting the rotor and stator together. This will fortunately change soon when the rotor will be made in a single operation. The current method however is very flexible.
4000W in a small package. Double carbon on both sides of the sandwich for added strength.
My work shop "Stilleben"
The exhaust cone before fitting to the shroud. My measurements have shown that the incorporation of the cone in the exhaust has some effect on the performance, particularly in the high power region. On the whole however, I came to no conclusion yet. I wi
View on the exhaust from the other side.
Exit cone for the WM400. The picture was taken with a wide angle lens so that the cone angle does not show well. At least the exhaust can be bought, so that the customer does not have to guess about the exit diameter.
The fan diameter can be made to suit the needs of the model in question between 120mm and 150mm. In it's 140mm form the efficiency of the fan is better than 0.88.
I designed and built two of these fans for a large A-10. According to the customer the WM2000 is largly superior to the TF4000.
Not only then but still today the Germans are at the very forefront of prop and fan development. The university of Darmstadt in connection with MTU has one of the most active departments for fan design and research.
Last one for today. I hope to show you the next pictures from my test rig.
Another view of the fan housing with the stator blades.
Not quite assembled but on the way (the shaft adapter is still missing)
The heart of the fan - the rotor with large tip chord for minimum losses.
View from rear end of main housing.....
Main housing with mounting lugs
and the other side. Note the reinforcement ribs and the two pairs of fixing holes.
A little bit dark - showing the stators.
As can be seen I used a Kontronik SEC which goes up to 55A (continuous) only, so the runs were only of short duration; sufficient for the test run and verification measurements.
Another view of the two fans.
WM1000 with Lehner 2240. I made a small air intake lip from foam (the blue ring at the front) to allow a smooth air flow into the transition piece. Even so the performance is short of spectecular.
View on trailing arm from astern. The angle of the crank to the horizon is actually more than shown here, i.e. 30 deg.
View on top of the trailing arm simulated by the alum. tube. In this plane the angle of the trailing arm to the centre line is 15 deg.
Main UC in its extended position.
Main UC leg made from a coat hager to show geometry. Main strut and trailing arm are in the stretched position. The stick indicates the length axis of the fuselage.
The (port) main UC in its retracted position. Including the "bent" axle will get the wheel perfectly flat.
By turning the axle the wheel changes it's angle relative to the trailing arm
Simulation of the "bent" wheel axle.
This photo shows the depth of the wheel well. There is plenty of space for the UC. The air duct above makes a real hump around the wheel well. Also good against radar echo.
the angles are not yet right, but one can see the principle
Another shot of the starboard UC
More turning of the axle....
The right hand (starboard) main UC arrangement is clearly visible with all it's actuators and links and struts.
the trailing arm looks a lot longer than it is really, caused by the wide angle lens of the camera. Interesting is the part at the end which carries the wheel. One can clearly see the rotating wheel carrier.
No exhaust air nozzle either (I have not made one yet)
This time I have used a short and only slightly flared intake, after some people complained that my measurements are to optimistic on account of the large bell mouth intake.
Looks nearly as big as a WM1000, but it is a WM600-90. Same dimensions as other 90mm fans and very light.
In the foreground are the various intake configurations tested and the standard exhaust nozzle.
After the first onset of duct buzz I had to reinforce the light weight ducts with some carbon tow. Adds around 10gram to the weight.
This does add some complications.
Up to here it's still "normal".
And from another angle
Just another view
Total of test arrangement. The dimensions are as close to your Mirage as I could make it (plus/minus a couple of mm).
Air entry formed into half circle and fuselage simulated by flat plate. This is perfectly adequate for static measurements.
This view gave me the first hint of the fairing to the lower launch rail.
Dramatic view of take off climb out
The shadowing gives away the top sculptor
Very good view showing the intricate shape of the fuselage top
The basics of the Main UC. It still needs some correections and additions.
Comparison of the two major F-18 versions. The top one is the one I use. The other top view further above shows the shape according to different sources
Another cutaway from the same source, but showing different details
Cut-away drawings are a great help, particularly when they come from the right source. This in combination with production photos give clues for the right structure and shape
The rotor mould
Rotor mould from the side. I should think that the whole weighs a lot mor than I can lift.
And this is the stationary part of the main housing mould, but it also opens up to release the housing, because of the reinforcing ribs around the housing outside.
The rotor mould fixed part
Another view of the main housing mould, this (I think) is the part which slides into the other to form the cavity.
The rotor mould movable half
The main housing mould.
The wing has a slightly negative rigging angle at the root. That explaines the extensive use of flaps and slats for the "mission adaptive wing".
Very simple front frames.
Frame at the position of the intake. What a strange shape.
This arrangement is for 1:12 scale. Just look at the cross section (scale) areas. The nozzle would normally be slightly more open, giving around 40cm^2, as in this case the WM600.
The wedge shaped cut will help to form the intake to fit the model.
Total duct length is now around 380mm up to the fan face. I would cut the duct to length in the model.
A view through the duct
110mm between those intakes, but see above (for adjustment)
Total width of the ducts around 205mm, but that can be adjusted when the duct is fitted in the model.
Another view of the duct flanged to the fan.
How the duct and fan go together. The two duct pieces can only be bonded together after installation in the model.
the starbord half of the duct. One can just see the flange outer connection and the spigot connection to the motor tube.
Minimal mechanical work still to be done. It's a question of the mould quality.
From a different angle. It shows that the blades are complete and without voids.
Basically the same as above
Just how it came out of the mould. Flash has still to be removed.
Here again the flex in the ducting. After correct shaping the duct will be reinforced with some carbon filaments wound around.
I don't know what BVM has to say to this??
A piece of intake lip held in position.
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