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# The jet propulsion with closed combustion type

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The biggest difficulties to realize the new type jet engine are:

1. The force that some parts bear are not steady, It is harmful for these parts. My method is make parts bear force from pulling force to pressure or both. Thus that would be better. But it will be a little weigh after this measurement.

2. To regulate the work procedure for high efficiency, safety, and economy is really hard, but the jet have to work under many circumstances. The simple countermeasures are: 1. Set the engine rotation speed within a certain range while working. Out off the tolerance the engine will be inefficient, even dangerous. 2. Change the turbine’s position to some extent, move it forward and backward; change the flow resistance in general pipe; change the shape of the general pipe. 3. If necessary we can add openings or bypass on the general pipe.

I have mentioned that there are two issues is the hardest to deal with for realizing the new jet. Though i proposed the solutions , I still usually review these solutions to improve them.

1. Some parts bear the unsteady forces.I designed three solutions and calculate and compare them to find out which one has the lightest weight. I prefer that the parts bear pressure sometimes and pull forces sometimes. The maximum magnitude of forces on two directions are silimar same. I think the trend of deformation became small and the whole weight is the smallest. It also need a container outside, otherwise the jet will be very light. I am not sure that the solution is better than others at each aspect. pls advise

2. As to regulate the work procedure, I analyze the mass current that spout out off the jet under many working condition with Engineering Thermodynamics. The result is optimistic. The jet can regulate itself automatically to ensure working steadily and orderly as long as we can control the engine rotation speed in a certain range. To control the speed is mainly because the wasted time on burning doesn't change much between high speed and low speed. In small case, we can change the turbine’s position a little in order that the turbine receives different energy.

This machine is so complicated that I corrected the solutions and ideas some times, pls forgive

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I am afraid that I didn't explain clear, so I compensate sth today.

1. Some parts bear the unsteady forces....... It also need a container outside, .....

It should be "......It also need a container outside to bear a small steady pull force...."

2. As to regulate the work procedure, I analyze the mass current that spout out off the jet under many working condition with Engineering Thermodynamics. The result is optimistic. The jet can regulate itself automatically to ensure working steadily and orderly as long as we can control the engine rotation speed in a certain range. To control the speed is mainly because the wasted time on burning doesn't change much between high speed and low speed. In small case, we can change the turbine’s position a little in order that the turbine receives different energy.

The action of the front door and back door(open & close) control the working courses mainly. The jet must work under various circumstances. We also need the jet accelerate or reduce speed at some time. I am concerned that the action of the front door and back door can adapt to the varieties after the jet is finished building and configuration under a certain condition.

I analyze the mass current under many conditions with Engineering Thermodynamics. The result is OK, the wasted time on flowing to a extent doesn't change . The jet can work steadily and orderly without additional adjustment as long as we choice the proper parameter when we design the jet originally. (I don't explain more about the conclusion, it is too long)Meanwhile we need to control the rotation speed in a range because the wasted time on burning doesn't change much between high speed and low speed.

Sometimes we may change the turbine’s position a little in order that the turbine receives different scale energy for a certain rotation speed.

Sometimes we need to change the proportion of fuel to air to get different performance, the jet can work steadily without addtional adjustment. Even though the volume of the fresh gas in once input changes, the jet also can work normally.

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1. to ensure combustion reliable and economical, we should control the proportion of fuel to air in a small range.

2. Before the gas enters the chamber,the gas get energy from the blower to increase pressure.the gas also get energy by flowing of air while the aeroplane flys. The energy on the two way be almost alternative each other .The two method also have almost same characteristic effect on the gas' parameter in the course.We can let them subsititute each other if nessary.

3. To control the rotation speed in a small range is important.It is relevant to sweeping away waste gas completely or not in varies circumstance.

If the rotation speed is too low,the jet can't sweep away the waste gas completely.

If the rotation speed is too high, the jet maybe have not enough time to complete combustion, or sweep away the waste gas over chamber into the branch pipe, it isn't proper.

Once the jet is designed and established under a appropriate condition. it can work under a rather wide condition without addtional adjustment.

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Just thought of another thing:

As the air flows through your jet, the moment the rotating 'compression door' closes behind it, the fuel-air mix would immediately lose a hell of a lot of pressure - prior to ignition. That should drop your performance considerably, too.

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make a modification.

......

If the rotation speed is too high, the jet maybe have not enough time to complete combustion, or sweep away the waste gas over chamber into the branch pipe, it isn't proper.

Once the jet is designed and established under a appropriate condition. it can work under a rather wide condition without addtional adjustment.

.......

If the rotation speed is too high,nut only the waste gas is swept out of the chamber by the fresh gas,but also some fresh enters the branch pipe. it isn't proper.

After we analyse the factors of the course: pressure, temperature, density of gas,rotation speed, the pressure outside in atmosphere.we choice a proper condition as base to design the jet, the jet can work normally under a rather wide circumstance if the jet can keep the rotation speed at a level.

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Just thought of another thing:

As the air flows through your jet, the moment the rotating 'compression door' closes behind it, the fuel-air mix would immediately lose a hell of a lot of pressure - prior to ignition. That should drop your performance considerably, too.

Hi,Boerseun

During the course that gas spouts out of chamber,the pressure in the chamber decreases,meanwhile the front door of chamber is closed. when the pressure in chamber drop to a extent (there is a range for the pressure),the front door open, the fresh gas enter and sweep away the waste gas. During the course of sweeping, the pressure in the chamber won't decrease rapidly because the fresh gas originally has a extent pressure(it has gotten energy from outside air's flowing and blower). the flow of gas in branch pipe and general pipe and the shape of the chamber also ensure the pressure in the chamber won't drop .

the last time of sweeping gas is very short. after the doors of chamber close, (maybe the front door and back door close at same time)the gas inside the chamber keep the pressure while flowing.

nearly completing sweeping in this pair of the chambers, the fresh gas enter another pair of chambers.( the pairs of chambers are close)

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Compensate!

I lost a important point when I explained the jet engine needn't addtion adjustment under many conditions.

....

2. As to regulate the work procedure, I analyze the mass current that spout out off the jet under many working condition with Engineering Thermodynamics. The result is optimistic. The jet can regulate itself automatically to ensure working steadily and orderly as long as we can control the engine rotation speed in a certain range.

.....

....If the rotation speed is too high, the jet maybe have not enough time to complete combustion, or sweep away the waste gas over chamber into the branch pipe, it isn't proper

I would like that the speed of gas at the outlet of general pipe is around sonic speed(1 M),and the pressure of gas at the point is around outside atmosphere's pressure. I will set it as base while I design the jet and analyse the jet work under verious conditions.

It will also be convient to design the jet .

(I omit the formular of calculation of mass current of gas). while the pressure increase from the base point, the mass current increase in proportion. so the jet can work normally in a certain range.

(per the characteristic of flow of gas under the pressure point)If the speed decrease from the base point,the mass current decrease more. So the fresh gas can't sweep out the waste gas completely. It would influence the thrust force and efficiency. But in most case the jet can work normally.

So to keep the rotation speed in a scale is important for the jet.

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• 2 weeks later...

After calculation, I think it is difficult that the rest of gas from the end of course of spouting ignites the new fresh gas because the energy of the portion is small. it hasn't enough energy to ignite the fresh gas.

So I suggest we can ignite the fresh gas from another chamber that is at the course of end of combustion or the beginning of spouting through a small pipe at the side of front door of the chamber. The pipe may be installed with the front door. Though the temperature of the pipe itself is very high: maybe 2800K, the most portion of pipe always be cooled in the fresh gas because it rotates with the front door. The strength requirement of pipe is low because it bear small force. we can find proper material for it.

We also can ignite the gas by the way of electic solution. one of poles is installed with the front door.

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After calculation, I think that the new jet engine need no tansimission gear box from turbine to the doors of chambers if the blower doesn't increase the pressure of gas much:only 1.3 -1.8 times of the former. The doors can be driven by turbine directly.Thus the rotation of doors are high,about 8000rpm.

The rate of the length of the chamber compare to its diameter is about 1.5 -2. The value is same for the branch pipes.

There is big possibility that closing the back door of chamber is earlier than the fornt door at the end of sweeping waste gas. The waste gas runs faster than the fresh gas because the waste gas's temperature is higher much.

All should be analysed carefully before performance.

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this engine sounds a lot like those that some of us loonies like to make for go carts using old turbochargers, two-cycle reed valves, thick wall steel tubing , and diesel injection componants .

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this engine sounds a lot like those that some of us loonies like to make for go carts using old turbochargers, two-cycle reed valves, thick wall steel tubing , and diesel injection componants .

Your discription is interesting. I think no matter how intereting it is, as long as it is high efficient and light-weight,realiable; comprehensively good, we should try.

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After calculation, I think it is difficult that the rest of gas from the end of course of spouting ignites the new fresh gas because the energy of the portion is small. it hasn't enough energy to ignite the fresh gas.

So I suggest we can ignite the fresh gas from another chamber that is at the course of end of combustion or the beginning of spouting through a small pipe at the side of front door of the chamber. The pipe may be installed with the front door. Though the temperature of the pipe itself is very high: maybe 2800K, the most portion of pipe always be cooled in the fresh gas because it rotates with the front door. The strength requirement of pipe is low because it bear small force. we can find proper material for it.

We also can ignite the gas by the way of electic solution. one of poles is installed with the front door.

If we use the burning gas or high temperature gas to ignite the fresh gas, the amount of burning gas into another chamber that just finishing sweeping gas(fresh gas enters meanwhile) should be proper. If the portion of energy is too small, it will ignite the fresh gas hard or in time because it can not increase the nearby gas’s temperature enough. If the amount is too big, the heat load and mechanical load increase a lot. That would be hard to deal with. The exact data of the components depends on the experiment.

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Good ol OPTIMISM!:) (Gotta love it!:doh: )

I've currently got two engines (one on the cart-one in my garage) one cart.

I have an aprox. 1Ltr. fuel tank which on average runs my cart for about 12 min. For fuel I use a mix of old motor oil 1 gal .5 gal gasoline .5 gal diesel and three gals kerosene (premixed in a 5 gal can) . The entire cart weighs aprox 200 lbs with my big-bum in it total weight aproaches 380 and flat out I've attained top speeds approaching 45 mph.

As for the engine in the garage I'm getting a little affraid to run it. IN my attempts to lighten it things are getting iffy!

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Good ol OPTIMISM!:xx: (Gotta love it!:) )

I've currently got two engines (one on the cart-one in my garage) one cart.

I have an aprox. 1Ltr. fuel tank which on average runs my cart for about 12 min. For fuel I use a mix of old motor oil 1 gal .5 gal gasoline .5 gal diesel and three gals kerosene (premixed in a 5 gal can) . The entire cart weighs aprox 200 lbs with my big-bum in it total weight aproaches 380 and flat out I've attained top speeds approaching 45 mph.

As for the engine in the garage I'm getting a little affraid to run it. IN my attempts to lighten it things are getting iffy!

I don’t study your material carefully because their characteristics or descriptions aren’t detailed. I don’t think the materials are fit to make the jet. The material can be fabricated as prototype to show the mechanical motion.

To implement this jet successfully, you must solve some difficulties: how to mix the fuel and air uniformly, how to ignite mixture gas quickly and reliable; how to design the flow pipe for high efficiency. You also need calculate: what frequency can it get? What current capacity do it has? How much is the push force? You must calculate something and do some experiment first. otherwise if previously you plan to let it fly but without the designed result, you may negate my idea.

After these preparation, even if you didn’t get the designed result at first, you easily to find and solve the problem.

Maybe you machine can work normally but it can’t fly, it is possible that the machine didn’t burning out enough fuel per second to provide enough force.

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how to mix the fuel and air uniformly, how to ignite mixture gas quickly and reliable; how to design the flow pipe for high efficiency. You also need calculate: what frequency can it get? What current capacity do it has? How much is the push force? You must calculate something and do some experiment first. otherwise if previously you plan to let it fly but without the designed result, you may negate my idea.

otherwise if previously you plan to let it fly but without the designed result, you may negate my idea. Huh??wuh??? I don't get it. Old idea...been done many times before....I've just been refining it!

With regards to the rest^ sitting in front of a computer doing calculation after calculation is for scientists and people that love to do math! There are those of us that simply take basic mechanical principles and a basic understanding of realworld physics and use this knowlege to make gadgets for our own entertainment. (ie jet powered go-carts, "burp jet" bikes (pulse jet), electric superchargers and other performance goodies for road vehicles. etc)

Have you ever modified an automotive A/C system to provide additional cooling from an intercooler?

I have with decent results, and I didn't do any fancy math or follow any fancy formulas. I simply took known facts, an understanding of how A/C systems work and an assortment of "spare" components from previous trucks I've owned and put the pieces together. Result one cold intercooler!

I have 20 years of automotive and diesel, 20 years of electronics, 15 years of hydraulics, 20 years metal working, and 15 years of agricultural/industrial equipment repair/overhaul experience and these are all I need. The day I need to monkey around with calculations and formulas is the day I hang up my tools and call it quits...I design and build for fun!

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Hi ,DFINITLYDISTRUBD:

I am sorry I can't be deside you,otherwise I explain detailed or I will help you do my best.

Your experience is good to manufacture the jet. maybe nearly enough. But you hasn't enough ability to design and calculate it. however it is nessary to made a new thing,It isn't that we are imitate something.

You should study Engineering Thermodynamics. or ask sb else to calculate it refer what I said before.

Though the jet is simple,after it is jet engine on the aeroplane!

what is "A/C system " you said?

Best regards

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Hi,DFINITLYDISTRUBD

maybe I didn't understand you very well.

While you make the model of the jet, I hope the components are distributed as the illustration I attached before. I have thought the construction for a long time.

I would like to do my best to answer your questions about the details in my design that I haven't mentioned.

Best regards

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