How many bars to rotate a motor 2 cv?

[Blackberry]

hello I would like to know how many bars it takes to run a 2 hp engine at full power.
is there a formula?
For info I would like to inject air into a small 2 hp engine to make it run and see how it reacts.
I know it's possible, I saw it done on you tube

[antoinet111]

would you have the link?

[Blackberry]

here is the link *
http://www.youtube.com/watch?v=ceonjJXgX2A

[antoinet111]

Thank you for the link, concerning the engine on youtube, it does not ask much (seen the hose)
on the other hand, it should be seen from the side of the negro guy and his work.

[Blackberry]

thank you for your message but this does not answer my problem of knowing how many bars to operate at most a 2 hp engine.

[dedeleco]

For the pressure p, the geometry of the motor is required: surface of the piston, necessary force given by the power P, the displacement x average the speed of rotation or number f of useful piston strokes per second !! (neglecting friction losses, not zero)
P = Spxf

or p = P / (Sxf)

[Janic]

to operate a 2hp engine with compressed air, it would be necessary to suppress the timing of the ignition advance and it is not certain that it works with the camshafts provided for thermal;

[Flytox]

to operate a 2hp engine with compressed air, it would be necessary to suppress the timing of the ignition advance and it is not certain that it works with the camshafts provided for thermal;

Especially the ignition is no longer useful but consumes power.
The camshaft must be very different, and rotate at the same speed as the engine instead of half. The entire cycle must be completed in a single engine revolution. Engine time on the descent of the piston with the intake valve open, intake closing in the PMB area, and opening of the exhaust on the piston rise, exhaust closing in the TDC area, etc.

The yield with a 4-stroke distribution must be shabby lower. (1 turn for nothing but with all losses)

[Janic]

flytox hello

Especially the ignition is no longer useful but consumes power.

of course, I was talking about the advance while thinking about camshaft timing. Here I am slapping myself! ouch!

[Christophe]

Before knowing the pressure, you must recall the camshaft! Air must be injected close to top dead center and once per revolution. The 2-stroke "compression / explosion" with closed valves are no longer useless!

P = Spxf

or p = P / (Sxf)

This formula gives an idea of ​​the minimum pressure to have in the case of an engine with 1 engine time per revolution.

With all SI units
I prefer to note N than f.

It is the "very" theoretical power, in reality it is necessary to correct by outputs (of expansion in particular: the pressure which leaves the engine will not be at 0 bar relative)