# What is lambda in air fuel ratio?

## 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…