Attachment 260684
So, I had some free time and I tried to connect your discution on pressure waves with EngMod p.waveforms.
The above waves come from my test engine, at it's peak BMEP rpm.
In Honda RS, Yam TZ250 pre-loaded engines as well as the (~)RSA engine I have in EngMod, at the encircle point, TFR pressure is still
above 1.
I added some letters to indicate points -me thought- of importance. Please correct me when I say something wrong in the following:
A: Ex port opens, flow starts there, pressure rises (why?). cylinder pressure starts dropping (still relatively too high). Tfr pressure irrelevant to Ex/Cyl pressure.
B: Ex pressure tops, flow speed tops. Cylinder pressure still dropping, gases exit. Tfr oscillate and starts rising, due to case/inlet pressure action.
C: Big depression in pipe, Ex pressure drops. Cylinder pressure drop dramaticaly, gases still exiting. Tfr open, pressure still rises.
D: Tfr pressure tops, start falling.
Blanks -lots of- follow.
E:
F:
G-K: Tfr pressure below 1. No flow?
K: Returning pulse from pipe arrives @ ex port, pressure starts rising. momentarily after, cylinder pressure starts rising. Tfr pressure rises a little more (flow?) before closing soon.
L: Ex pressure tops, a few degrees before closure. cylinder pressure rises, piston compressing hard. Tfr (closed) oscillation due to case/inlet action.
M: Ex pressure oscillation due to pipe action. cylinder pressure rises, piston truly compressing.
N:
Not much, but I have no head to combine every part's action into more analysis right know.
Hope I had a few right's above..
It would be very interesting to know what happens to TFR pressure and it falls at [C,F]. Also at [G,K] and their impact on flow.
(sorry, I ate a few letters after G - brains are pulverised as I said).
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