Identify the false statement from the choices provided?
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Answer: D. In quality governing, quantity of fuel is varied to suit the load and total charge of air is varied
Explanation
In quality governing of internal combustion engines, the fuel quantity is varied to suit the load. However, the total charge of air is not varied simultaneously in pure quality governing systems. Therefore, stating that the total air charge is varied makes this specific statement false. Quality governing adjusts the fuel-air ratio while keeping the intake air volume constant. Quantity governing varies the volume of the fuel-air mixture while maintaining a constant ratio. Diesel engines commonly utilize quality governing by injecting varying amounts of fuel into constant air.
Engine designers select governing methods based on specific fuel efficiency and load requirements. Understanding engine governors helps optimize performance across varying industrial operating conditions. Incorrect governing assumptions can lead to poor combustion efficiency and excessive emissions. Option A is true because petrol engines often utilize quantity governing for smooth throttle response. Option B correctly describes quantity governing where the air-fuel ratio remains nearly constant. Option C accurately explains hit-and-miss governing used historically in older stationary engines.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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