[DFINITLYDISTRUBD]

In my momery, the piston engine's the intake valve and exhaust valve aren't the reed valve type.Why do you the one has the valve?

Your 2-cycle engines can work @25000rpm. It is too high. it is out of my image............................................. .................................................. .................................................. .................................................. .....

technically Yamaha probably never intended for their motorbike motors to be run so hard (20,000 rpm plus) the tachometer on my bike "redlines" (the numbers are red and the motor should not be reved beyond this point) at 16,000 but the numbers go to 25,000 and I as my own personal bike mechanic
have no qualms about "pegging" the needle (reving so high as to push the needle all the way around the guage to the pin the needle rests on when the engine is off). I've personally pushed my 1971 Yamaha 100cc LS2 to speeds in excess of 110+mph (granted it takes a lot of road but it can be done I've heard of speeds exceding 170mph with 100cc bikes)

As to reed valves in piston engines most small two strokes some small 4-strokes (Subaru 3-valve 3-cylinder motors come to mind) and all big diesel two strokes have them at least as an intake valve.

[DFINITLYDISTRUBD]

What is the movement formation of reed in reed valves? Can it allow a lot of gas pass the hole?
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gate type. Yes, depending on size they can flow 200cfm+ to 1200cfm+ easily.

[qumf]

Dear DFINITLYDISTRUBD:

You told me a lot of information. I can't distinguish which engine you ever used, which engine you plan modify for the jet engine.
You said you would modify the piston engine weigh 20 lbs,does it include the turbo-charger?You told the flow 200-1200cfm.does it referred the engine with 20 lbs?
Only considering the weight of 20 lbs and 1000 cfm intake current(assumed),i think the engine is very good though it can't compete with current jet.I have calculate the my jet roughly and i have some main parameters of some current jet.
So there is a question,in my design,the gas with energy only need to push turbine,Your engine need to not only push turbine but also pistons. Thus it will be easy to control the the gas flow.But it will consume more energy.Less energy will be used to accelarate the gas comparatively.
In my opnion, you need modify the turbine a little to allow the gas get more energy after turbine.the nozzle should be designed as it can be adjusted .The higher rotation speed the engine gets, the better.if only safety.
What I say is for your reference.

[DFINITLYDISTRUBD]

My engine is a turbine type no piston I only refer to the two-cycle engines to explain the nature of some of the componants that are borrowed from diesels and two-strokes because it's cheaper and simpler to modify existing componants that I have handy rather than to purchase the machine tools necessary to manufacture them.

PARTS LIST:

1- 9" turbo
1- 4" dia. .25" thick wall pipe 1' in length
1- fuel delivery and flow regulation system
1- ignition system (spark, glow, or both depending on fuel)
1- reed valve (overall size- bigger is better)
1- 4" dia .25" thick wall pipe 1" long

ASSEMBLY:
1- attach 1" long thick wall to output of compressor of turbine (turbo charger)
2- mount fuel injector through 1" long thickwall pipe
3- Affix reed valve to 1" long thick wall pipe (post injector)
4- attach 1' thickwall pipe to reed valve
5- attach opposite end of thick wall pipe to input of turbine
6- plumb fuel system into thickwall pipe
7- wire up ignition system with spark or glow plug in 1' long pipe as close to reed valve as possible
8- provide fuel and electricity
9- using a high output air supply such as a leaf blower or shop vac (place leaf blower output to compressor input) start turbine!!!!!!!!

[qumf]

Dear DFINITLYDISTRUBD:

you simplify the idea of the new jet. I still have sth to clarify:
1. Where does the fuel burn? In thick wall pipe or reed valve?
2. In my engine every chamber has two doors: the front door and the back door. I adopt them to ensure closed combustion. Does it have two doors in the combustion place? Do you use two reed valves? Or Does your valve have two reed if combustion happen in the valve?
3. after turbine, you should add a pipe as nozzle that also should be adjustable at the size of opening.
4. What is the pressure in your compressor? I did understand your design clearly. sorry.

I remind you:
1. to mix the fuel into air uniform is very important. it can ensure burning quickly.
2. I have several chambers cooperate to provide steady force. You might have one chamber, it will cause big vibration.
3. Because you can't calculate precise orginally (It is really hard to calculate). I suggest you add a valve or bypass between the compressor and chamber for the adjustment of gas.

good luck for you!

[DFINITLYDISTRUBD]

The higher rotation speed the engine gets, the better.

As far as I've been able to track down the info on it the max safe rpm for an automotive turbo is between 180,000 and 200,000 rpm. As tested in my engine max rpm capability is about 148,000 rpm. For my needs this is plenty fast enough (especially as my head is a mere 3" or so from it when I'm driving my
"test mule" or as my misses puts it "death trap" !!!!!)
I have a genuine fear that pushing it (the engine) to it's limits may result in the turbine "grenading" (exploding) and filling my head with shrapnel.

As a drag racing (legal and illegal) fan I've seen the under-hood results of pushing turbo's too hard and it was'nt pretty!!

[qumf]

[quote=DFINITLYDISTRUBD]As far as I've been able to track down the info on it the max safe rpm for an automotive turbo is between 180,000 and 200,000 rpm. As tested in my engine max rpm capability is about 148,000 rpm. For my needs this is plenty fast enough (especially as my head is a mere 3" or so from it when I'm driving my
"test mule" or as my misses puts it "death trap" !!!!!)
I have a genuine fear that pushing it (the engine) to it's limits may result in the turbine "grenading" (exploding) and filling my head with shrapnel.
QUOTE]

I think you can use a steel case or enclure(mayber 2 layer) to cover the engine to ensure your safty. You can make some small holes in it to watch it and intall necessary sth.

[DFINITLYDISTRUBD]

1. Where does the fuel burn? In thick wall pipe or reed valve?

Post reed valve in 1' pipe

2. In my engine every chamber has two doors: the front door and the back door. I adopt them to ensure closed combustion. Does it have two doors in the combustion place? Do you use two reed valves? Or Does your valve have two reed if combustion happen in the valve?

Initially it had a reed valve at each end of the combustion chamber (the 1' pipe) now it only has one at the intake of the combustion chamber.

3. after turbine, you should add a pipe as nozzle that also should be adjustable at the size of opening.

I'm still experimenting with nozzle design. Currently I have an adjustable "flap type thing" essentially three pieces of thickwall pipe cut into wedge shaped slices that are pulled into a convex conical shape by cables which when slack allow for a concave shape (basicaly forced open by exhaust from the turbine).

What is the pressure in your compressor?

To be perfectly honest I've no idea. Typicaly when a turbo charger is used for it's "intended function" (to utilize exhaust pressure and flow to force air into a recipricating or rotary engine to increase manifold pressure and therefore horsepower by allowing more air and fuel to enter the engine) it is capable of generating over 50 psi on conventional automotive engines this pressure is regulated by a "waste gate" which opens to allow some of the exhaust gasses to bypass the turbine to prevent pressures in the cylinders from exceeding acceptable levels (typically only professional drag racers dare to run pressures over 35psi. the average family auto will only run about 10 psi max. much more than this cost and reliability become an issue)

[DFINITLYDISTRUBD]

I think you can use a steel case or enclure(mayber 2 layer) to cover the engine to ensure your safty. You can make some small holes in it to watch it and intall necessary sth.

Believe me I've seriously considered it!!!!!!!!
The only issues are that to install a shield with enough strength to withstand such a blast would add at least another 30 to 50 lbs just to protect my head and another 20 to 45 lbs for fire protection for the rest of me All in all that's anywhere from 50 to 95 lbs of extra weight to get moving so the gain in rpms and thrust would likely be eaten up by the losses caused by additional weight. It just doesn't seem worth it.

[qumf]

Originally Posted by DFINITLYDISTRUBD

Post reed valve in 1' pipe

Initially it had a reed valve at each end of the combustion chamber (the 1' pipe) now it only has one at the intake of the combustion chamber.

Why don't use a reed valve at the end of outlet of the combustion? cloesed combustion has more efficiency though it mat be hard to control?

Do you only use only one chamber?

Maybe i misunderstand you. If you can draw a picture, It will be better.