Vivian Meazza wrote: > y = -0.25x3 + 0.15x2 + 1.11x > > Thinking about the over-speed situation overnight, the Merlin was > allowed to go to 3600 rpm for brief periods, and even then damage to > the engine was possible. This is a normalised value of 1.2. The K > Series will go to 9000 (don't try this on yours - it requires special > valve lifters and crankshaft) or 1.28 normalised. The curve shown > here:
Yes, but remember that the "normalization" RPM isn't guaranteed to be a maximum speed. It might be for your merlin configuration, but I can guarantee you (seriously: 100% certainty) that if we include a model that goes wacky in some regime, someone will come up with a configuration to tickle the bug. This has happened again and again, often with your aircraft. :) How about this one instead: ln(rpm_norm - 1) * (1 / ln(2)) It seems to qualitatively match the curve you posted (is there a primary source for that curve?) without the nasty dropoff. You can see how it works, it just translates/scales a logarithm curve to pass through the origin and (1,1). Let me know. Andy _______________________________________________ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
