What is lambda in air fuel ratio?
The air-fuel ratio, or lambda number (λ) determines the mass ratio of air and fuel in the combustion chamber, as it relates to the stoichiometric air-fuel ratio. When λ=1, ideally balanced combustion conditions result in neither oxygen starvation nor excess.
What is the formula of air fuel ratio?
The ideal (theoretical) air-fuel ratio, for a complete combustion, is called stoichiometric air-fuel ratio. For a gasoline (petrol) engine, the stoichiometric air-fuel ratio is around 14.7:1….Air-fuel ratio, lambda and engine performance.
| Fuel | Chemical formula | AFR |
|---|---|---|
| Butanol | C4H9OH | 11.2:1 |
| Diesel | C12H23 | 14.5:1 |
| Gasoline | C8H18 | 14.7:1 |
| Propane | C3H8 | 15.67:1 |
What is the ratio of lambda?
Lambda represents the ratio of the amount of oxygen actually present in a combustion chamber compared to the amount that should have been present in order to obtain “perfect” combustion.
How do you read a lambda air/fuel ratio?
Another way to look at air/fuel mixture is lambda value. It is represented by the Greek symbol “λ.” Lambda equals AFR divided by stoich. When measuring air/fuel mixture using lambda, stoich will always equal one (1) for any fuel.
When to use Lambda to calculate air fuel ratio?
Because Lambda = 1.000 when the oxygen and combustibles are in perfect stoichiometric balance, Lambda can easily be used to calculate Air-Fuel Ratio for particular fuels.
How is the AFR measured in a Lambda meter?
Lambda Meter Measurement of parameter λ (Lambda) air / fuel ratio (AFR) Wide band lambda probe measures the numerical value of the ratio Air Fuel Ratio – AFR or parameter of λ (Lambda) by measuring the oxygen content in the exhaust gases, but it can only work in a pair with a special controller.
How is the a / f ratio of air fuel determined?
At the stoichiometric point, Lambda = 1.000. A Lambda value of 1.050 is 5.0% lean, and a Lambda value of 0.950 is 5.0% rich. Once Lambda is calculated, A/F ratio can be easily determined by simply multiplying Lambda times the stoichiometric Air-Fuel ratio for the fuel selected – e.g. 14.71 for gasoline, 15.87 for LPG, and 17.45 for CNG.
What is the lambda value for perfect combustion?
We all know that perfect combustion requires an air/fuel ratio of approximately 14.7:1 (by weight) under normal conditions. Thus a lean air/fuel ratio of, say, 16:1 would translate to a lambda value of 1.088. (To calculate, divide 16 by 14.7.) A lambda of .97 would indicate an air/fuel ratio of 14.259:1…