Aim LCU-ONE CAN, Руководство пользователя

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4
3 – What is lambda
Lambda represents the ratio between the actual mixture of air/fuel (A/F or AFR) admitted in the engine, compared to the optimum ratio
(A/F
stoichiometric
or AFR
stoichiometric
) indicating an efficient fuel combustion. Lambda can be written as:
𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿 =
𝐴𝐴 / 𝐹𝐹
𝐴𝐴 / 𝐹𝐹𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆ℎ𝑆𝑆𝑆𝑆𝐿𝐿𝑖𝑖𝑆𝑆𝑖𝑖𝑆𝑆𝑆𝑆
=
𝐴𝐴𝐹𝐹𝐴𝐴
𝐴𝐴𝐹𝐹𝐴𝐴𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆ℎ𝑆𝑆𝐿𝐿𝑖𝑖𝑆𝑆𝑖𝑖𝑆𝑆𝑆𝑆
where:
A
= parts of air (oxygen) in the combustion chamber
F = parts of fuel in the combustion chamber
To completely burn one part of gasoline, 14.57 parts of air (AFR
stoichiometric
) are required.
This optimal combustion is also indicated as
Lambda = 1,
whatever is the fuel in use.
AFR
stoichiometric
is a fuel dependant constant. Oxygenated fuels and additives will change this value, thus it is strongly recommended to use
Lambda as reference parameter.
3.1 – Rich mixture
If the actual mixture has less than 14.57 air parts to 1 part of gasoline, the mixture is said rich.
For example An AFR of 12.2 is a rich mixture and is also indicated as:
84 . 0
57 . 14
2 . 12
= =
Lambda
Lambda < 1
AFR < 14.57
(for gasoline)
3.2 – Lean Mixture
If the actual mixture has more than 14.57 air parts to 1 part of gasoline, the mixture is said lean.
For example an AFR of 17.5 is a lean mixture and is also indicated as:
2 . 1
57 . 14
5 . 17
= = Lambda
Lambda > 1
AFR > 14.57
(for gasoline)
3.3 – Stoichiometric mixture
If the actual mixture has 14.57 air parts to 1 part of gasoline, the mixture is in the stoichiometric ratio.This is also indicated as Lambda = 1