On 11/10/02 at 4:02 AM Julian Foad wrote: > >As for the guts of how the engines are modelled ... I first worked on >the starting and stopping behaviour of the JSBsim engine. The >thermodynamic model of the engine is probably very good
Parts of it are, parts of it aren't and are overdue a re-visit. >but there's lots >of yucky stuff there to do with starting etc. I've done some stuff >there, and in the sound configuration, but not finished. I'll go into >that later. > Ah yes, starting, I seem to recall a lot of hacking and kludging to get everything to work :-) There's a number of problems currently: 1/ My assumption of cranking speed at the time (480rpm!!!!!!!) was *way* too high. 2/ There's currently no friction modelled, which means there's not enough resistance to a proper starter motor torque at very low rpm when there's no prop resistance (I put a friction model into the LaRCsim IO360.[ch]xx to resist the prop when the engine was switched off in flight but I haven't brought it over to the JSBSim one yet). 3/ Need a proper starter motor torque curve. I did dig one out at one point but never put it in and now I've lost it. I'll have another look. Part of the problem is that I have to make sure that I'm working from publically available data and not anything internal. Have fun :-) Cheers - Dave _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
