Hi again guys,
Mike said :
beautiful work, Luc! Any plans of putting more points on the curve, like mid and low power settings? Maximum thrust is a good data point to have, but is almost certainly not the economical cruise power.
Okey ... One thing you have to understand, is that many of the features advertised by Eugene (i.e : Fully trottlable) were pure advertisment features.
Let me explain in details what "Trottle Settings" you have in a pressure jet operations (Almost none).
First, when you start this engine, you have to let it warm-up for aprx. 40 sec. At close to 100 psig. of pressure and if you go to low on the warm-up pressure, it won't lock and your 2nd stage will get red hot and difform. At this point, the maximum thrust you will see is probably lower then 50 pnds.
Then, when it is warm enough and you bring that pressure to 110 psig. the engine goes in reasonance and jump immediatly to 100 ponds of thrust.
The remaining 55 psig that you have (To reach 165 psig.) will give you your additional 25 to 30 pounds of thrust, for a 130 pounds total.
So, your real throttle capabilities are from aprx. 100 to 165 psig. and from 100 to 130 pnds of thrust. So, there is not alot to do with the additional curve point you refer to. That "Fully Throttlelable" feature is again, advertising bull shit.
And furthermore, there is a catch in the pressure jet. Let divide the engine operations as follow :
Setting #1 will be the start/warm-up/Lock setting.
Setting #2 will be reasonance Low Power (100 pnds of thrust)
Setting #3 will be reasonance Max. Power (130 pnds of thrust)
Okeyyy ... Know this now. Operating and 130R engine, you have to do the 1, 2 and 3 scequence and then you get that 130 pnds max. power figure.
If you throttle the engine between 2 and 3, without EVER dropping out of reasonance, you can always go back to that 130 pnds max. power figure.
BUT ... If ONCE ... You drop below that #2 setting and drop out of reasonance, then, when you will get back in reasonance ... NEVER Again, you will see that 130 pnds. max. power.
So that is why ... "Fully Throttlelable" becomes "Little throttlelable" and once your out of reasonance, there is no coming back there. You have to shut the engine down, let it cool and start again.
Now imagine ... You are flying an helicopter equipped with this engine and sudently, a draft of dusky wind bring your engine out of reasonance (Like we saw it happen so many time here). You are stuck in a "Must Shut Down" situation and you are going DOWN. I sure you will have a very UNPLEASANT experience.
Now you know...Why this engine never made it in the sky. It is a pretty risky buiness. But perfect for any vehicles that stay on the ground.
It is my beleive that what killed the possibility for this engine to find his place in our world ... Was Eugene Stuborness to put this engine on a flying machine.
And no Mike ... Considering the above, there is no more plans to find SFC's in different power settings ... It would be useless to do so.
I hope the above will clarify the SFC and throttle saga or issue.
Luc ........ Out