Cessna skylance tc T182T, Информационное руководство

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CESSNA SECTION 7
MODEL T182T NAV III AIRPLANE AND SYSTEM DESCRIPTION
GFC 700 AFCS
U.S.
ENGINE
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TURBOCHARGING SYSTEM
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1. Engine induction air is supplied through an opening in the lower
cowl, ducted through a air filter and into the compressor where it
is compressed.
2. The pressurized induction air then passes through the throttle
body and induction manifold into the cylinders.
3. The air and fuel are burned and exhausted through the turbine.
4. The exhaust gases drive the turbine which, in turn, drives the
compressor, thus completing the cycle.
The compressor has the capability of producing manifold pressure in
excess of the takeoff maximum of 32 in.hg. In order not to exceed 32
in.hg., a waste gate is used so that some of the exhaust will bypass the
turbine and be vented into the tailpipe.
It can be seen from studying Steps 1 through 4 that anything that
affects the flow of induction air into the compressor or the flow of
exhaust gases into the turbine will increase or decrease the speed of
the turbocharger. This resultant change in flow will have no effect on
the engine if the waste gate is still open because the waste gate
position is changed to hold compressor discharge pressure constant. A
waste gate controller automatically maintains maximum allowable
compressor discharge pressure any time the turbine and compressor
are capable of producing that pressure.
At high altitude, part throttle, or low RPM, the exhaust flow is not
capable of turning the turbine and compressor fast enough to maintain
maximum compressor discharge pressure, and the waste gate will
close to force all of the exhaust flow through the turbine.
When the waste gate is fully closed, any change in turbocharger speed
will mean a change in engine operation. Thus, any increase or
decrease in turbine speed will cause an increase or decrease in
manifold pressure and fuel flow. If turbine speed increases, the
manifold pressure increases; if the turbine speed decreases, the
manifold pressure decreases. Since the compression ratio approaches
3 to 1 at high altitude, any change in exhaust flow to the turbine or ram
induction air pressure will be magnified proportionally by the
compression ratio and the change in flow through the exhaust system.
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T182TPHBUS-00 7-41