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The Computer and Improvement of the Engine Carburetion System
Technical Paper
745080
Sector:
Language:
French
Abstract
Attempts are now being made to solve the problem of adapting
spark-ignition engines and fuels by using varied concepts such as
Research, Motor and Road Octane Numbers, Engine Severity, Lead
Bonus, etc. All these open the way to statistical analysis rather
than an interpretation of phenomena. The only reason these concepts
have been developed is because of the fineness of the multiple and
complex interactions of the phenomena involved, all of which have
made theoretical methods unusable.
The aim of this paper is to show that the reaearch done by
I.F.P. and partially sponsored by G.I.M.T. make it possible to
build models for the overall engine/fuel behavior in the range of
light knocking. The basic parameters for such models are: spark
timing, compression ratio, volumetric efficiency for the engine and
equivalence ratio, ignition delay for the air fuel mixture.
After demonstrating that it is possible to go from the
pressure-temperature history to the delay properties:
τ= A exp (B/T) p-n in which A,B and n, are properties of
the air fuel mixture
we demonstrate that high and low running conditions knocking can
be explained by the same formula.
As an example, it is shown that the model can be used to
simulate the important effect of volumetric efficiency on knock.
The mini-computer system developed to store and process digitalized
pressure values is then described.
The paper concludes with an examination of the possibilities
offered by such a method for both engine and petroleum
industries.