The advantage the constant-volume combustion type gas turbine engine

[qumf]

For years I always hope to find a way to estimate the time spent for each work course: combustion, spouting out off the chambers, exchange gases by suction (fresh gas and burnt gas) in chambers.
According to the data from some manuals about the internal combustion engine, I know the combustion course need several millisecond to complete. They have similar condition for combustion referred to combustion theory.
Until to the recent days, I find a way to estimate the time spent on later two courses. I study the principle and motivation of the gases in chambers and branch pipes ,I study their change on the gases conditions and interactions ,at last find the reasonable one after many times of hypothesis. That basically is based on Engineering Thermodynamics.
By calculation, each course costs also at the same level of millisecond. Thus the whole work cycle can continue even if accord to the current layout. Of course a few parts' sizes and proportion need to be adjusted a little and some features should be noticed.

 

[qumf]

I always think of how to expand the use of the engine,recently I think over if it can be used as the jet engine on the rocket flying in atmosphere.Because in this field engines usually are used once, the engine neednt those reinforcement parts, the engine will be much lighter.
Compared with ramjet, this jet engine can start at much lower flying speed., because by this type of combustion the ignition is easilier.
The engine has some advatages in the field, the turbine, compressor, and even most vane wheels can be cancaled if the rocket flys in very high speed.
It is possible that the back door of the combustion chamber can be omitted if the fuel can mix into air vey well in front of chambers and burn out very soon insides the chambers. thus the general outlet pipe also can be abandoned. but the branch pipes for outlet must be retained.
of course the shape of chambers and branch pipe will be studied carefully and changed a little.
The front door of the combustion chambers rotates and is driven by the inlet gas through a simple way, which provide kinetic energy while the rocket flys at very high speed. after all the rotation need not much energy.
the whole structure can be simplified a lot ,meanwhile some reinforcement and safety parts are ignored, the whole weight will decrease a lot as long as it is used only once and short time.

 

[qumf]

I have stated the functions of the branch pipes for the output gas,A reader ever mentioned the front door of the chambers is a importent one. Turly!

I summarized the three main functions of the front door. They must be realized.
1, As the passage for the input gas which let the streams of mixed gas enter chambers in turn and orderly.
2, As the wall to form the combustion space with chambers, so it bears the considerable force and heat, but they are basically stable for the front door while working.
It is very important to control the clearance with the end face of chambers. It need a special structure.
3, As the passage for the blame from burnt chambers to refresh chambers to ignite the mixed gas.

So the shape of the front door need to be considerd carefully, to allocate each place/space of the front door to realize the three main functions.

 

[KennethLangr]

Although it won't improve efficiency much, there are also no moving parts in the inlet ducting for the CT inlet pressurization proposed by myperfectworld - using some compressed air to create a venturi effect to "induce" more airflow sounds plausible. Loss of output in warm ambient or at higher elevations is a significant problem. (See Mechanical Engineering Thread) On a costant volume CT (land based power generator,) a motorized fan could also be used - but of course pressure pulsations and potential fan blade failure upstream of the compressor would be a concern. A compressor stall could also result if the combustion process didn't back down fast enough as result of the booster fan or auxiliary "blower?" shutting down unexpectedly.

 

[qumf]

Thank for your reply.

Though there is a little words in your reply which I can’t understand, I try to explain as possible as I can.

If I design the engine with one pair combustion chambers, one pair outlet pipe, the problem you worried will happen probably. But I design it with several pairs of chambers, and several pairs of branch outlet pipes and a general outlet pipe. These aspects will improve a lot. Thus they can cooperate, some certain process must need help from other process in other chambers or other pipes.
For a few issues you mentioned, it will exist no matter what type engine, even if you choose constant-pressure combustion engine.

On the other side, I will set a minimum startup speed. (an rotation speed for the engine). Only within a proper speed, the engine can work orderly.

I will give a sketchy feasibility report about heat and force later though that mainly can be got from internet already.

What does “CT” mean in your reply?

 

[KennethLangr]

Sorry. CT is combustion turbine.

 

[qumf]

Recently I think we can simplify the engine, the compressor will be cancelled, replaced with a fan or a pipe. The inlet gas pressure before combustion will decrease a lot and the total efficiency will be smaller definitely.

After studying the principle and designing the structure carefully, the modified one can suck the air from outsides automatically. Meanwhile the structure after combustion will change to be simple.

Thus the engine is like the current detonation engine to some extent. But it may be easy to realize comparably. I think.

 

[DrClaude]

PF is not a platform for the dissemination of one owns work.

Thread closed.