Understanding Engine Combustion Ratios
Complete combustion occurs when a fuel burns completely with oxygen, producing primarily carbon dioxide and water. For internal combustion engines, this requires a specific mixture of air and fuel.
Stoichiometric Air-to-Fuel Ratio
The ideal ratio of air to fuel required for complete combustion is called the stoichiometric ratio. For gasoline (petrol) in typical internal combustion engines, this ratio is approximately 14.7:1 by mass. This means about 14.7 parts of air are needed for every 1 part of fuel.
Selecting the Correct Option
Comparing the theoretical value of 14.7:1 with the given options:
- 14.6
- 11.2
- 12.1
- 15.5
The value 14.6 is the closest to the standard stoichiometric air-to-fuel ratio for complete combustion in internal combustion engines.
Important Questions from Energy and Environment - Teaching
- Which of the following fuels has the highest HHV carbon intensity ?
- Burning of 1 mol of $\text{CH}_4$ liberates 890 kJ of energy and 1 mol of $\text{CO}_2$. Since 1 mol of $\text{CO}_2$ has 12 g of carbon, the higher heating value (HHV) of methane is :
- Consider solar insolation of $400 \text{ W/m}^2$ incident on a single solar cell of area $100 \text{ cm}^2$. If only $15\%$ of the photons cause electron - hole pairs and the average energy of incident photons is $\sim 1 \text{ eV}$, the short circuit current of the cell is :
- In terms of the calorific value, identify the correct sequence :
- At a given location the wind speeds are predominantly in the range $6$ to $6.4 \text{ m/s}$. This location’s wind power class will be termed as :
