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The jet propulsion with closed combustion type


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THEY'RE HEEEEEEEEERRRRRRRRRRRRE!!!!!!!!!!:cup:

They are finally here!!!!!:confused:

So so happy!!!!!!!!!:confused:

will update as soon as I get time to play with them (and eventually install them!)

 

Q thanx for your patience:)

 

DFINITLYDISTRUBD:

 

I have questions to you:

1. What is the size of rotary valve, such as diameter?

2. what the size of the turbine and the compressor(the diameter of wheel)

3. how manys times of opening per a rotation? or how manys times you want it to do?

4. Do you use one chamber or several coupls of chamber?

5. do you want to use double wall for the chamber? I think it would be better if you adopt?especially you will make a formal jet engine later.

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looks like the inside of a pulsating shower head. alot like a rodial engine.   purty neat engines here http://www.keveney.com

Dear DFINITLYDISTRUBD:   I suggest firstly you fixed the engine with a shelf. after adjust it ,it can work normally, You let it drive your cart.

dear all:   I always think whether the new jet can work under various conditions. to adopt some cases if it must be adjusted.   In some cases we hope the jet provides less push force than common. I a

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1. What is the size of rotary valve, such as diameter?

2. what the size of the turbine and the compressor(the diameter of wheel)

3. how manys times of opening per a rotation? or how manys times you want it to do?

4. Do you use one chamber or several coupls of chamber?

5. do you want to use double wall for the chamber? I think it would be better if you adopt?especially you will make a formal jet engine later.

 

 

1.-9" outer, 8.5" inner @ throat, 1" square per gate opening, 6 openings total

2. 14"T & 6"C

3. 6

4. one chamber

5. double wall has it's advantages but I'm thinking 0.25" stainless pressfit or welded into an aluminum skin with cooling fins

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DFINITLYDISTRUBD

 

1. Could you give me a simple conception drawing of your engine?

2 .Do you use one rotary valve or two valves?

3. The double wall for chambers have some advantages because the chambers bear rariable force. we can think out a way to make outer wall bear a consistant around half of force by the gas or mechanical way, make inner wall bear a smaller variable force. You can not to do so if the load condition is not serious.

 

4. I still have the question: if you only use a chamber and it can spout gas 6 times per rotation. In which angle of position in a rotation(circle) does the chamber suck the fresh gas? because it is continous inside the chamber,gas goesout from one opening, the gas around other gates(closed) can flow through the opening? if the fresh gas enters the chamber from another side of the chamber meanwhile, It is easy confused with the waster gas. from the aspect of gas pressure the fresh gas is also hard to enter smoothly.

Maybe I haven't understand your engine well so that i have the question.

 

Maybe your chamber is divided into several cells.

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A reader reminded me that there are some energy waste occurs when the gas runs from the branch pipes into general pipe because the gas with different conditions from different pipes encounter. I admit.

It is hard to estimate that how much energy loss. What I can do is to analyze this waste’s principle. I designed the branch pipe that make the gas in general pipe more steadily than without the branch pipes. It has the effect of cushion that reduce the change of the gas condition because the gas’s spouting is similar to impulse. 2. by the branch pipe, sweeping the waster gas can perform in another chambers. 3. When actual design the branch pipes’ size and sharp, I should make the gas’s condition from different branch pipes in different course close at the position as possible as I can.

Fortunately the amount of gas from sweeping course (or the gas similar to the course) must be much less than the amount of gas from the spouting course, so the loss is small.

We should control the pressure and the direction of the velocity of gas from the different pipes, as well as the amount of the different gas to reduce the loss.

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In which angle of position in a rotation(circle) does the chamber suck the fresh gas?

??????????????????????????????????????????????????????????!!!!!!

the six openings per rotary valve are open for 30 deg. of rotation and closed for 30 deg. The intake (rotary valve) is out of phase to the exhaust (rotary valve) to yield closed combustion for 15 deg. per pulse six times per rotation.

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??????????????????????????????????????????????????????????!!!!!!

the six openings per rotary valve are open for 30 deg. of rotation and closed for 30 deg. The intake (rotary valve) is out of phase to the exhaust (rotary valve) to yield closed combustion for 15 deg. per pulse six times per rotation.

 

Dear DFINITLYDISTRUBD:

 

I try to underatand what you wrote. I guess you change my design. I hope you succeed. But the space in your chamber is continuous, to do as you want maybe can not sweep the waster gas clearly, thus waster some fuel.

 

I hope I can do my best to help you or cooperate with you, I also hope I can build the jet by myself, but in my place,it is hard to get these material to build the jet. I still need think it over carefully.

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Dear DFINITLYDISTRUBD:

 

thank you tell me these information, i am happy.

I just am a little surprised why you use only one chamber and ensure it can work normally, I think it is not perfect. To seperate the chamber into several cells is not hard. You have prepared the most things,why don't do a little more?maybe I am misunderstand.

some little things i remind you. I guess you picked the turbo-charger from truck, not special order. In any case,you should refered the rotation speed of the turbo; the gas pressure from the compressor. the common flow speed from the compressor.The informations are easy to get and very useful for you.

How is the valve driven? by turbine directly?

 

Could you give me a photo of the jet?

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yes the turbo is from a truck...the valve is driven directly by the turbine...one chamber is simpler to make and cheaper to test with...I'll try it first then if all is well modify and possibly make it a multichamber.

as for rotational speed the turbo is capable of 180,000 rpm plus without failing,pressures achievable depend on chamber size fuel, air mix, and operating rpm...but typically turbo's can achieve 50psi+. I have no idea how many cfm these can achieve (guess I should research it). The key to the whole engine is how many cfm at how many psi per rpm.

 

Will keep you updated! :doh:

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DFINITLYDISTRUBD:

 

Great.

 

Maybe the turbine needn’t so high rotation speed.

Maybe you should modify the turbine later because the turbo originally is for truck.

As to the flow speed, you can refer the size of the turbine, and the common rotation speed, times them to get speed in turbine. It is a rough method.

 

I have started to study “theory of combustion”, but just for knowing main concept. the more I learn, the more feasible I think my engine.

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I compensate a little:

 

As to the flow speed, you can refer the size of the turbine, and the common rotation speed, times them to get speed in turbine. It is a rough method.

 

“size of turbine” should be “the radius of turbine wheel”

 

If the rotary valves are driven by turbine, you should reduce the rotation speed from turbine to the valve . The speed of turbine is too high for valve because the combustion need time.

 

It is interesting that two persons cooperate for a machine from two countries by Internet.

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DFINITLYDISTRUBD:

 

I have no idea how many cfm these can achieve

 

How to estimate the cfm of the turbo?

Because you picked the turbo-charger from the truck, you can know what engine is fixed the turbo(or similar engine), you can know the approximate displacement and the RPM of the engine, then you can know the cfm of the compressor. But the cfm is possible maximum value. The actual value is less than it.

I also think pressure 50psi higher, but if actual currency volume(displacement)/working frequency is bigger than the originally engine in truck, and it is in proper range, the pressure will decrease.

 

I still worry if the rotary valve can bear the high pressure.

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I feel little guilty that I can not help you more. I have not more practice experience than you about the current engine. I believe that you can find the specification. Don’t worry, the time and money spent on the preparation must be repayed later definitely.

There are some courses haven’t be figure out clearly. I must leave my mind into the courses.

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I think the compressor and turbine’s specification you found are ranges, you should know how wide range they can work, including the several related parameters’ change trend in the range. Which point is the most efficient, which point is used most frequently? Those are useful for your work.

You should think which point is fit for your engine? You can make how wide variation while modification.

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