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The jet propulsion with closed combustion type

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That's likely qumf; the problem with math is that it's never as good as actually building the thing and sitting there manually moving it's parts around to make shure they fit correctly.

I'd suggest you go to the nearest automotive race track and go check out the pit crews; ask them who is the best macheineist they know. ask all the pit crews, and listen to the guys that get first or second place all the time. If ten guys tell you they all use this one macheine shop, but all ten get in the bottom ranks, you know that macheineist sucks.

of course you're going to have to show up with your calculations on each peice and the tolerances written down, but make shure the macheinist goes over tehm with you and that you both understand what each part does. once that's out of the way you'll have something a lot more concrete to play with.

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pls see the diagram, I analynize the 4 cources of the new type jet engine.

As to the current jet, You can easely find it in manual.

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pls see the attachment

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pls see the attachment

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pls see the diagram, I analynize the 4 cources of the new type jet engine.

As to the current jet, You can easely find the relative analynise in some manual.

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Pls see the work cycle in the diagram.

Now we can know the information of the current jet: such as the temperature and pressure of every course(altogether 4 courses). We can calculate the whole efficiency for turbine and push force.(not possible efficiency).

I design the new type jet, so I can calculate the each step's temperature and pressure. So I can calculate the whole efficiency accurately.Pls see attachment of diagram.

from the analynize, I find the efficiency of the new type jet is lower than the current jet because it is unvaried volume while burnning.(pls see explanition in the diagram, the "k"). it is lower by 8%-12%. fortunately it is referred to whole efficiency(turbine and spouting gas). it isn't refer to spouting gas.(the whole energy that can be utilized includes motion energy for turbine and spouting for push force)

For the reason the effiency of spouting decrease a little. But the efficiency of spouting is still higher than the current jet by 49%.That is I need, in the whole the new type is economical.I don't show my calculation again here. pls see the post before.

Meanwhile the highest temperature and pressure in the new type is higher than the current. But they are discontinuous. they last very short time in every cycle.So the parts (including turbine)can bear after I modify their structure.When the gas encounters the turbine, the gas's temperature has reduced a lot because of expansion.

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I complete the diagram about the new jet's working cycle. pls see.

coclusion:

Though the efficiency of new type jet is lower than the current, But it can contribute much energy to push force; use very little energy for turbine. So it is economical in the whole. the efficiency on push force is average 50% more than the current jet .

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Hi,everyone

A friend reminded me that I may make a mistake while calculate efficiency. The date picked from turbine-generator may be a little different than the jet in aeroplane. So I decide analysis the working course strictly by formular. Pls see the attached picture, it would be strict.

on the other side, I might should re-consider the efficiency(before I misunderstand the term)

Regrading to type jet, refering the attached picture:

k=1.4 ;U=10 ; W=1.5 efficiency=42%

k=1.4 ;U=10 ; W=1.8 efficiency=45%

Regarding the current turbine-generater, W=10 efficiency=48%

Because the compressor costs a lot of energy and its efficiency is very low(60%),the real efficiency of the jet is 43% maximum, When it is used in aeroplane, the efficiency will be lower (maybe less than 35%).

From the upper analysis, the two type jets' efficiency are similar, while the jet begins to move, my jet's condition will turn better than the current jet(because it can suck more air and the air's pressure increase obviously than the current).

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I forgot to tell you another advantage of this new type jet engine. It avoid to use a compressor. To manufacure a big volume compressor is really hard, especially high efficiency, big volume compressor. Only few companies in the world can make this kind of compressor.

The pressure of the air flews into my jet's chamber needn't be so high. Thus the air can be provided by a blower. The blower is much easy to made comparatively. They are different things.

:hihi: Essentially as to my new idea, I change to another way to get high-pressure gas. That is by closed (don’t change volume) combustion

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Hi qumf

Looking at your diagram at the start of your post, the blower section. I see two stages of blades and two stages of stators and a chamber before the combustion chamber. Is this chamber there to supply a ready volume at pressure for the combustion process. Your blower duct is parallel, will it stay that way.

Any blower detail would be interesting,

regards Dave R

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especially high efficiency, big volume compressor.

should be corrected as" especially high efficiency, big air-current compressor.

Essentially as to my new idea, I change to another way to get high-pressure gas. That is by closed (don’t change volume) combustion

I should add a sentense" however the solution inceases some difficulties of controlling the course"burnning;spout gas;enter gas(meanwhile sweep waste gas)"

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Hi qumf

Looking at your diagram at the start of your post, the blower section. I see two stages of blades and two stages of stators and a chamber before the combustion chamber. Is this chamber there to supply a ready volume at pressure for the combustion process. Your blower duct is parallel, will it stay that way.

Any blower detail would be interesting,

regards Dave R

Dave:

Originally I didn't place anything between the blower and combustion chamber. It is empty. You misunderstood.

The space is necessary.For now I think I should add something at that position. the function is " mix the fuel and air more better; let air current flow steadily for blower;make some preparation for gas into chamber not very continuously " meanwhile the flow resistance is small.

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Having any success?

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Having any success?

I have enough money to do the project.

Since I can't do, i hope somebodyelse can do, I will try my best to cooperate.

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An adversary always mentioned me that my new type jet has lower efficiency than the current jet. I feel what he said isn't appreciate.So I must add some adendum.(pls see the attachment about analyse the efficiency of the two kind of jet, I attached before)

1. While I calculate the current jet's efficiency, I choice the best parameter for it, W=10, efficiency=48%

If I choice the best parameter for my jet, U=11,W=2; efficiency=48%. Two type jet have same efficiency in academic.( I choice 11 for U while burning uses up nearly all air in chamber,by the fuel the gas can get the temperature,then calculate the increase of pressure under unvaried volume situation.)

2. As to my jet, while U=10,W=1(blower only suck air,not increase the pressure of air); efficiency =35% It is amazing.

3. The efficieny is an important factor to choice the jet. But it is the only criterion. I state a obvious example, For now the aoroplane fly under 1M speed.(under sonic speed). Under the situation, genelly the internal-combustion propellor type has bigger efficiency than jet, but people would like to use jet as aeroplane engine.

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correct!

...I state a obvious example, For now the aoroplane fly under 1M speed.(under sonic speed). ....

corrected as" ...I state a obvious example, For now over half aoroplanes fly under 1M speed.(under sonic speed). ....

I am sorry to this mistake.

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Hi qumf

Looking at your diagram at the start of your post, the blower section. I see two stages of blades and two stages of stators and a chamber before the combustion chamber. Is this chamber there to supply a ready volume at pressure for the combustion process. Your blower duct is parallel, will it stay that way.

Any blower detail would be interesting,

regards Dave R

Dave:

I forgot to tell you some information:

For now I decide to spray fuel into air at the blower position,or near the blower position.maybe by the blades of the blower

As to ignite the gas in chambers, I have three ideas.

1. install some instrument inside the chambers, ignite the gas at proper occasion.

2. ignite the mixture gas at proper occasion by the burning gas from the previous chamber through the front door.

3. ignite the fresh mixture gas by the burned gas in the same chamber at the beginning of the fresh gas entering the chamber.I think it is feasible at a certain frequency.

We practise to find what is reliable and economical.

pls propose,

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