Now It Can Be Told ... Cyclodyne Revealed

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by fastnova » Thu Sep 03, 2009 4:58 pm

I cant believe I only just came across this…
I have only had time to have a look at the drawings as of yet, but at a glance I see a striking similarity to Bruno’s BCVPE.
Maybe this is just the eyes of the inexperienced.

I might just have to put aside my tesla for a while, am getting a little tired of drawing disks anyway…
I don’t see problems, only opportunities.

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by Ghrey » Fri Sep 04, 2009 6:41 am

I just re read this thread, with perhaps less tired eyes.

My toroidal CC design was intended to capture pressure in an accumulator and use it for ram air augmentation. Never got built. Your engine is a simple build by comparison...

A few other denizens of my note books have this feature, in one form or another.


My current PipeJet, ( made from plumbing ) an Annular ( I call it coaxial like the cable... ) Build will employ it as part of the principal of it's design....
But as a exhaust stack booster so as to not rarify the incoming air, and hopefully cool that one critical part of the CC end of the tail pipe so it does not over heat.

I will keep you posted.

In the process of moving, from the glorified phone booth we had to the house we have.

No real time to work on jets, more space, no time.

Life still complicated.

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by uberjet » Sat Sep 05, 2009 3:57 am

wow i really like the design alot!! i might integrate it with my new project!

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by jprindustria » Thu Feb 18, 2010 4:15 pm

larry cottrill wrote:EDIT: Be sure to see the IMPORTANT CLARIFICATION post, below!

Someday you'll all thank me for this. Or, maybe, curse me ...

Tomorrow I will be a mere 62 years old. I am now tired of sitting on a design that will never be hatched (by me), so here it is for all the world to see, laugh at, etc. This is the one-and-only, ill-fated Cyclodyne engine design, as submitted to and rejected by NASA away back in 2001. There are many things wrong with it, which I will gladly and freely discuss with any and all interested parties on this forum. (Not that I wouldn't still like to get back to this someday, but it doesn't seem likely any time soon, so why not let others "enjoy" messing with it?)

To all my friends who signed the Cyclodyne Engine Non-Disclsure Agreement: You are hereby now absolved of any obligation to hold confidentiality. I'm sure this is a great relief to all of you, after being on the edge of your seats about this ever since 2001.

Nevertheless, I would like very much to see someone build an engine based on (NOT identical to) this idea. So, here's my plan:

I will award as a prize to the FIRST builder to get a Cyclodyne-derived engine to self-sustain, regardless of any apparent realized thrust performance, my prototype FWE Lady Guinevere valveless engine. Yeah, I know, it never did run, but it will make somebody a nice souvenir / remembrance (yes, I do plan to live forever, just not around here where you can get hold of me). So if you want a nice conversation piece, just build up your very own Son of Cyclodyne and get it to run unassisted for a minimum of five minutes, and the Lady is yours to keep.

The PDFs are EXACTLY as submitted to NASA, except for some minor redactions of personal contact information. Be sure to read through the text carefully. It does not read like a Clancey novel -- more like a table of logarithms. Of course, many of you have never seen a table of logarithms. Oh well.

Good luck! May the best steel butcher win!

L Cottrill

sr. cottril
my name is pablo rossaroli of Argentina, I wondered if this engine handles any kind of oscillation or simply the air inflow is constant. excuse my groin, I'm using google translator

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Fri Mar 12, 2010 4:09 pm


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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Fri Mar 12, 2010 5:37 pm

Soy de Argentina :D y tengo un ramjet con un ductedfan que quiero hacer volar. Siempre leo esta página y me gusta mucho.
Les describo mi motor:
Unidad fan: hyperflow 56mm, motor ammo 4875 kv,290 w aprox.
Baterias: 11,1vol, 2200 mAh. 25C
rpm 45.000. aprox.
Velocidad admision 60m/seg,(area salida 90% de area del fan).
Caudal M 0.088 kg/seg
Area salida del fan al 90%, 16 cm 2 = area menor del difusor.
Area mayor del difusor 70 cm 2 = area cámara de combustión.
Angulo de divergencia del difusor 18º,con perfil curbo interno.
longitud del difusor 120mm
Longitud cámara de combustion 190mm
Tobera convergente a 20º con area de salida de 31 cm 2

Temperatura de entrada 300 ºk
Temperatura de cámara de combustión 1273 ºk
Relacion de temperaturas: 1273 ºk/ 300ºk = 4.243
Relación velocidades: Raiz cuadrada de 4,243 = 2, o sea un 200% de aumento del empuje primario,(del fan).
Cosumo de combustible liquido aprox. 6 gr nafta por segundo...

Pesos del motorjet:
Ducted fan+motor ammo 4875 kv+ESC GWS 35 AMH 100 GR
Difusor de aluminio de 0,2mm 50gr
Cámara de combustión y tobera de acero inox. de 0,2mm 125gr (chapa adelgazada a martillo para lograr el espesor)
inyector y retenedor de llama 30gr

Baterias lipo 11,1 vol y 2200 mAh 25 C 220gr
Nafta 1000gr (para tres minutos a maxima potencia)
Aerosol gas 120cm 3 60gr (para presurizar el tanque de comb. liquido)
Avion 700gr (balsa en celosia

Total 2285gr

Empuje caliente máximo: 10,5 N ( 0.088 kg/seg x 120 m/seg)
Relacion peso empuje al despegue 0.43 :1 (un poco pobre pero suficiente para volar).
Tener en cuenta que con el consumo altisimo de combustible liquido que el motor tiene, la perdida de peso en el tiempo es tambien bastante grande, o sea que la relacion empuje peso aumenta rapidamente.La cuestion es el despegue.
La idea es mantener constante una relación empuje peso de digamos 0.35 : 1,(lo cual segun mi experiencia con modelos con ducted fan ,es mas que suficiente para mantener un jet electrico en vuelo)o sea que cada vez consume menos combustible y se puede alargar el tiempo de vuelo un poco,digamos a 4,5 minutos,mas que suficiente para mi.
Si por ejemplo ud. mantiene el máximo empuje por un minuto, al cabo de este tiempo el avion pesaría 1925 gr, y como el empuje sigue siendo de 1kg, la relacion empuje /peso subiria a casi 0,52 : 1. La curba de descarga de las baterias es mucho mas plana que la del combustible. A los dos minutos de vuelo, el avion pesaria 1565gr,y la rel. empuje / peso sube a
0.63 : 1,lo que combinado con una velocidad de salida de 120m/seg,y un avion limpio, digamos que podria volar a una velocidad de 84 m/seg, 300 km/h. si consideramos que la resistencia al avance es del 70% de la velocidad total del chorro.
Pienso poner un motor mas potente, digamos uno de 5400 kv y 350 w, que aumenta muy poco el peso,(unos 20gr de motor y60 gr de baterias de mas capacidad),pero que pueda trabajar sin calentarse demasiado en un consumo de 30 amh.La velocidad de admicion subiria a unos 75 m/seg,(tener en cuenta que esta potencia en un fan de 56mm de diametro ronda las 50.000 rpm lo que mejoraria un poco mas el rendimiento,que crece con el cuadrado de las rpm.
En general el diseño tiene muy en cuenta los pesos de los componentes.Por ejemplo, la nafta,(la uso porque tiene buen poder calórico y es "liviana 0,72 kg los 1000 ml),es bombeada a la serpentina del motor por un pequeño aerosol lleno de gas.
No hay bombas de combustibles,ni ESC, ni baterias extra. La presión medida en la cámara de combustion cuando el motor tiene un empuje caliente de 800 gr,(crucero), es de nada mas que 0.009 bar(1,009 si tenemos en cuenta la presión atmosferica ),y la presion del gas es de entre 2 a 3 kg/cm 2.
Tambien sirbe para el arranque,ya que es necesario precalentar la serpentina que vaporiza el combustible.
Estoy trabajando en el control de la mezcla de la valvula del combustible y la potencia del fan,para mantener en todods los regimenes de potencia una relacion estequiometrica y la mayor velocidad posible de aire. Para bajar el empuje, la idea es disminuir el caudal de aire,manteniendo constante la velocidad y la temperatura de la cámara,para no arruinar mas el pobre rendimiento del motor.La tobera esta calculada para que pase el caudal inicial,que es practicamente el mismo que el final sin tener en cuenta la masa del combustible aportada, a 1000ºc. Si se excede esta temperatura,hay que aumentar el area de salida porque se sobrepasa la maxima presion disponible para esa velocidad del aire de admisión,y la llama va en sentido contrario y destruye el fan...
El motor tiene una longitud total de 450mm y un diametro maximo de 95mm.
Es muuuuyyyy importante no poner NADA que toque la chapa de la camara de combustion porque por ella queda una delgada capa de aire que no deja que se ponga demasiado caliente. El retenedor de llama va en el cono interno del difusor y solo asi,cuando funciona al maximo,apenas se pone(vista desde afuera),la camara de combustiñon al rojo palido.
En fin queria compartir mis cuestiones de hobby con uds que son mis "maestros espirituales" en todo esto.
Cuando tenga el modelo final voy a subir el video correspondiente,enfocando especialmente la balanza que mide el empuje,mas que las llamas que salen por la tobera. :D

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Fri Mar 12, 2010 7:23 pm

I'm from Argentina and I have a ramjet with a ductedfan I want to fly. Always read this page and I really like.
I describe my engine:
Each fan: HyperFlow 56mm, ammo motor 4875 kv, 290 w approx.
Batteries: 11.1 vol, 2200 mAh. 25C
rpm 45,000. approx.
Speed 60m/seg admission (90% departure area of the fan area).
Flow M 0.088 kg / sec
Area fan output to 90%, 16 cm 2 = area under the diffuser.
Area increased diffuser area 70 cm 2 = combustion chamber.
Diffuser divergence angle of 18 º, to curb domestic profile.
diffuser length 120mm
Combustion chamber length 190mm
Converging nozzle with 20 ° exit area of 31 cm 2

Inlet temperature 300 ° k
Combustion chamber temperature of 1273 º k
Relation of temperature: 1273 º K / 300 º k = 4243
Velocity: square root of 4.243 = 2, ie a 200% increase in the primary thrust (the fan).
Liquid fuel Cosumes approx. 6 g naphtha per second ...

Motorjet Weights:
Ducted fan + ammo 4875 kv motor + ESC GWS 35 AMH 100 GR
Diffusion of aluminum of 0.2 mm 50g
Combustion chamber and stainless steel nozzle. 0.2 mm 125gr (sheet thinned to hammer to get the thickness)
injector and flame retainer 30g

LiPo Batteries 2200 mAh and 11.1 vol 25 C 220gr
Nafta 1000gr (for three minutes at maximum power)
Aerosol gas 120cm 3 60g (to pressurize the tank comb. Liquid)
Avion 700gr (raft in lattice

Total 2285gr

Push hot maximum: 10.5 N (0,088 kg / sec x 120 m / sec)
Takeoff thrust to weight ratio 0.43: 1 (a bit poor but enough to fly).
Note that the Most High consumption of liquid fuel that the engine has, the weight loss over time is also quite large, meaning that the weight increases rapidamente.La Thrust question is the takeoff.
The idea is to maintain a constant thrust weight ratio of say 0.35: 1, (which in my experience with ducted fan models, is more than enough to keep electric jet in flight) or whether they ever use less fuel and can be lengthen the flight time a bit, say to 4.5 minutes, more than enough for me.
If for example you. maintains the maximum thrust for a minute, after which time the plane would weigh 1925 grams, and as the thrust remains 1kg, the Thrust / weight would rise to nearly 0.52: 1. The curve in discharge of the batteries is much flatter than the fuel. Within two minutes of flight, the aircraft sorry to 1565gr, and rel. thrust / weight ratio rises to
0.63: 1, which combined with a muzzle velocity of 120m/seg, and a clean plane, say you could fly at a speed of 84 m / sec, 300 km / h. considering that the drag is 70% of the total velocity of the jet.
I put a more powerful engine, say one of 5400 kv and 350 w, increases very little weight (about Y60 gr 20gr motor bigger capacity battery), but not too hot to work in a consumption of 30 amh . The speed to cancel a registration would rise to about 75 m / sec (note that this power a fan of 56mm diameter round the 50,000 rpm which would improve a bit more performance that grows with the square of rpm.
In general, the design takes full account the weights of componentes.Por example, naphtha, (the use because it has good heat and power "light 0.72 kg 1000 ml) is pumped into the engine by a serpentine small gas-filled aerosol.
There are no fuel pumps, or ESC, or extra batteries. The pressure measured in the combustion chamber when the engine is hot thrust of 800 grams, (Cruise), is nothing more than 0.009 bar (1.009 if we take into account the atmospheric pressure) and gas pressure is between 2 3 kg / cm 2.
Also sirbe to boot, since it is necessary to preheat the coil that vaporizes the fuel.
I am working on controlling the mixing of the fuel valve and the power of the fan, to keep todods regimes potentially a stoichiometric ratio and the air as fast as possible. To lower the thrust, the idea is to decrease the air flow, keeping the speed and temperature of the camera, but not to ruin the poor performance of motor.La nozzle is calculated to pass the initial flow, which is practically the same as the final regardless of the fuel mass supplied to 1000 ° c. If you exceed this temperature, increase the output area because it exceeds the maximum pressure available for the intake air velocity and the flame goes in the opposite direction and destroy the fan ...
The engine has a total length of 450mm and a maximum diameter of 95mm.
It is important not to muuuuyyyy NOTHING to touch the plate of the combustion chamber because it is by a thin layer of air that leaves it gets too hot. The flame retainer is in the inner cone of the diffuser and only then, when running at maximum, just put (viewed from outside), the camera combustiñon pale red.
Anyway wanted to share my hobby with pc issues that are my "spiritual masters" in all this.
When in the final model I'll upload the video in question, focusing especially the balance which measures the force, but the flames coming out through the nozzle. hectmarr

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Sun Mar 14, 2010 9:20 pm

Sorry.Maybe the subject of my toy engine was not appropriate in this space and in these circumstances. I'll try again in another area of :(

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Sun Apr 10, 2011 8:34 pm

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Fri May 09, 2014 8:19 pm

Project : EDF- Afterburner
Experimental findings .

I find it important to share my findings with respect to this project, since much has been made of this issue in many forums , and for a long time, and I have had very good results in the analysis and experimental evaluation of this device.
I enjoyed reading this, so for this question , I decided to invest some of my time to clarify things. As someone said, " The management is the worst is not done ."
For this reason I make available of all , what I did .
I do not know if it will be of interest to someone , at this time, but I think I should share this work .
Engine runs correctly, producing an increase of 100% thrust , without reaching the limit of development I think, as apparently , still oxygen in the combustion chamber to burn more fuel, raising the temperature and speed over gas escape and get more thrust.
In this video in my previous post , the variation of static thrust of EDF alone and cold 800gr , 1600gr is observed with hot afterburner on.
The problem has no solution, is the consumption of fuel, which is much question that limits the autonomy short time and its use in model aircraft, because I think that 5 or 6 minutes of flight , is the minimum and standard you can be in the air . I use regular gasoline .
Heat that mass of air at about 1000 C , according to the stoichiometric ratios necessary for good combustion , needs a lot of fuel. In mechanics and thermodynamics are no miracles ...
This engine always operates with afterburner . It is a hybrid engine , it is not feasible to use the EDF and at times activate the afterburner , because the increase in weight of the afterburner system, particularly the fuel required , ruins the thrust / weight of course you could use drone relationship. Apart from this, you must use a variable geometry nozzle to accommodate this issue . Enlarges the more are the hot exhaust gases, and shrinks when colder .
Adding to this "problem" , missed only EDF thrust ( push cold ) , due to the afterburner system in the diffuser inlet in flameholder etc. . The latter losses are not many, the biggest problem is the weight of the fuel limits the autonomy to one or two minutes, because otherwise , the relationship thrust / weight of all the Aeromodel , low quickly.
However, it is perfectly possible to use this hybrid motor, hobby applications , where 1 or 2 minutes are sufficient thrust . Here is a good design because it is of low economic cost , low-tech , very loud, quite spectacular to see and quite powerful ! , Could be reached rather higher than those obtained with only EDF speeds.
The speed of the exhaust gas is doubled with the afterburner ... literally remaining constant mass flow provided by the EDF .

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Re: Now It Can Be Told ... Cyclodyne Revealed

Post by hectmarr » Fri May 09, 2014 8:24 pm

Here is a video with parts of the jet engine :D

And the engine running, (and I was more up but it seems no one saw it) :(

This video shows a prototype built with the diffuser in fiberglass.

I apologize for my bad English, I hope you understand me. regards

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