Hi all,
Der P2 klingt wie ein Rallyeauto, und diese Zwitscherthematik haben wir schon mehrmals durchgesprochen... auch wenn im Film das Wastegate genannt wird, das ganze ist ein Zusammenspiel aus Turbo, langen Wegen und dem BOV.
Das Wastegate (soweit ich weiss, siehe auch hier: http://en.wikipedia.org/wiki/Wastegate) wird ja quasi als Druckbegrenzer verwendet, d.h. es oeffnet, wenn der Turbo mehr Druck macht als er soll. Das Zwitschern kommt aber, wenn man vom Gas geht... ergo wenig Druck... da passt doch was nicht zusammen... ALS knallt normalerweise so dermassen, dass man das Zwitschern nicht mehr hoert...
WIKI schreibt auch was zum "Wastegate Chatter Myth":
<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Wastegate Chatter Myth
There is a common myth in the automotive world about so called "wastegate chatter", a noise created on lifting off the throttle in a turbocharged car. The sound is commonly described as a chipmunk or a rattlesnake. This sound is in fact caused by a component called a blowoff valve (BOV) malfunctioning or being incorrectly setup. The BOV releases the excess pressure (from turbocharging/supercharging) between the throttle flap and the turbo when the throttle closes. However when this volume of air is too large the BOV cannot release it all and the pressure is vented back through the compressor turbine. As the air passes back through the turbine the pressure wave is "chopped" by the still spinning turbine creating the fluttering sound that is commonly termed wastegate chatter.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
Dazu passt dann auch die Erklaerung von GOFASTBITS:
<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Blow-off valve myth #2: The fluttering sound is usually believed to be the blow-off valve. In reality, it is caused by a blow-off valve, but does not come from the blow-off valve. If the spring pre-load is adjusted too tight, this will cause compressor surge, which as described above is the sound of air exiting the turbo.
Compressor surge: You can think or surge as the point at which the compressor blades begin to slip in the air, losing their pumping ability, much like an aircraft wing loses its lift when it stalls. In a turbo, this happens in a series of bursts, as the blades slip, then bite, slip then bite. This sets up a pulsing wave in the turbo piping and explains why the sound has that characteristic flutter.
The interesting thing about compressor surge is that it occurs much more readily at low turbo shaft speeds. At these low shaft speeds, on road cars this is generally between 2000 and 3000 RPM, compressor surge is not much of a problem, as the loads generated by the surge are miniscule compared to what the turbo encounters at high boost. However, if surge occurs at high RPM and boost, it is possible to reduce the turbo life and/or damage the compressor. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
Sorry fuer das Englisch, aber es gibt kaum deutsche Versionen dieser Texte...
Lest mal
diesen Beitrag. Der hilft sicher weiter...
Gruss,
Jan 
the boost is strong in my family. my car has it, my club has it...and my friends...yes,it's you - you've got it,too 
Freitag, 19. April 2024, 23:14
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