Delphi Multec 3.5, Руководство по применению

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Multec 3.5 Fuel Injector Application Manual Fundamentals
Delphi Energy and Chassis Systems Revision: 11/05-1 2-17
Figure 2-4 - 50% Vapor / Liquid Ratio vs RVP, Fuel and Pressure
Note:
Refer to Section 5
Fuel rails are typically specified as either full recirculation, limited
recirculation and returnless. The ability of the fuel rail to purge vapor is
dependant upon whether the fuel can be recirculated back to the fuel tank
from the location of the individual injector in the fuel rail. Due to
increasingly stringent evaporative emissions requirements, there is a
need to reduce fuel tank temperatures, which in turn is driving many
engine applications to a returnless fuel system. It therefore is becoming
increasingly important to consider the effect of hot fuel handling on
overall system performance.
Returnless fuel systems have been shown to require at least 7.3 psi (50
kPa) higher operating pressures to maintain the same hot fuel
performance as a recirculating system due to higher fuel temperatures,
and the lack of ability to purge vapors from the rail (See Fuel Rail
Assembly Applications Manual).
50% Vapor / 50% Liquid Temperature of Gasoline and E-10
350 & 400 kPa System Pressures
70
80
90
100
110
120
130
7 RVP 8 RVP 9 RVP 10 RVP 11 RVP 12 RVP 13 RVP 14 RVP 15 RVP
Fuel
Temperature (C°)
Gas-350 kPa
E10-350 kPa
Gas-400 kPa
E10-400 kPa