Oleksiy Frolov wrote: > 1. Wing lift change because of the propwash in twin engine airplane. 2. > Prop discing effect on high rpm and low torque, where propeller actually > produces negative thrust in close to 0 blade angle.
1. No, YASim doesn't model inter-surface wash and flow effects. The only airflow the surfaces see is the global one. 2. Yes, sort of. YASim does model negative blade pitch (albeit in an abstract coordinate space where "pitch" is a factor, not an angle) Whether it does so well or not is an open question. I don't know anyone who has compared it to a real aircraft. > What simulation algorithm was used in YASim to simulate the turbine and > propeller physics for turboprops ? It's an energy balance model based on a nominal efficiency curve specified by the configuration. This has the advantage of working really well in the middle of the operating range, leading to good thrust estimates even with minimal input data. The disadvantage was mentioned above: performance at the extremes of the performance regime (windmilling, for another example) tends to produce funny effects. Some of this can probably be tuned away for a given application. Andy ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Flightgear-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/flightgear-devel
