How does engine pressure ratio affect the efficiency of an engine?

A high overall pressure ratio permits a larger area ratio nozzle to be fitted on the jet engine. This means that more of the heat energy is converted to jet speed, and energetic efficiency improves. This is reflected in improvements in the engine’s specific fuel consumption.

How does bypass ratio affect specific fuel consumption?

The amount of fuel used per thrust is called thrust specific fuel consumption (TSFC). As bypass ratio (BPR) increases the overall efficiency of the engine increase which is a primary factor that yields lower TSFC for the turbofan engine.

What happens when pressure ratio increases?

With further increase in compression ratio, the increase in pressure ratio results in a decrease in the network output. It can also be concluded that the thermal efficiency increases with increasing pressure ratio.

Why is engine pressure ratio important?

Engine Pressure Ratio (EPR) is a means of measuring the amount of thrust being produced by a jet engine. EPR system design automatically compensates for the effects of airspeed and altitude.

How do you increase compression ratio in an engine?

1. By reducing the cylinder diameter(to increase the compression ratio).
2. By increasing the cylinder diameter(to decrease the compression ratio).
3. By reducing the cylinder length/stroke length(to increase the compression ratio).
4. By increasing the cylinder length/stroke length(to increase the compression ratio).

Why have a high bypass ratio?

Bypass provides a lower fuel consumption for the same thrust, measured as thrust specific fuel consumption (grams/second fuel per unit of thrust in kN using SI units). Lower fuel consumption that comes with high bypass ratios applies to turboprops, using a propeller rather than a ducted fan.

Does SFC change with altitude?

As altitude increases air mass flow into engine decreases, thrust also decreases for same throttle setting. But combustion efficiency deteriorates with altitude which requires more fuel to produce same energy than at lower altitude. So, SFC increases at altitude.

What is SFC in aviation?

Specific fuel consumption (SFC) is one of the most important metrics employed in aviation.