How does an afterburning engine work?
The afterburner simply injects fuel into the hot jet exhaust stream. It ignites, adding to the hot gases shooting out the back of the engine (see this Question of the Day for details on afterburners). At full force, the plane can get up to more than Mach 2. Because afterburners are highly fuel inefficient. A typical afterburner works by pumping additional fuel down the exhaust pipe , increasing exhaust velocity and thus thrust is increased.Afterburners generate a larger amount of thrust by accelerating the air mass passing through the engine, without the need to increase the engine size. This rapid acceleration of air is achieved by injecting fuel into an extended exhaust nozzle section.The advantage of afterburning is significantly increased thrust; the disadvantage is its very high fuel consumption and inefficiency, though this is often regarded as acceptable for the short periods during which it is usually used.Afterburners would add a lot of fuel consumption and noise during take-off. Typically, in most cases, airliners are required use the “minimum noise abatement” procedures during take-off. Also using engines with afterburners would reduce the engines’ fuel efficiency during climb and cruise.
Can turbofan engines have afterburners?
Afterburning turbofan Since the 1970s, most jet fighter engines have been low/medium bypass turbofans with a mixed exhaust, afterburner and variable area exit nozzle. An afterburner is a combustor located after the turbine blades and bypass duct in the jetpipe. Due to their high fuel consumption, afterburners are only used for short-duration, high-thrust requirements. These include heavy-weight or short-runway take-offs, assisting catapult launches from aircraft carriers, and during air combat.The afterburner can be used on an F-16 for a limited time, depending on the amount of fuel available and the altitude of the flight. For example, at low altitudes, it can use the afterburner for about 11 minutes with internal fuel only, or about 19 minutes with external fuel tanks.The afterburner increases thrust primarily by accelerating the exhaust gas to a higher velocity. While the mass of the fuel added to the exhaust does contribute to an increase in thrust, this effect is small compared to the increase in exhaust velocity.
Can you put an afterburner on a turbofan?
Most modern fighter aircraft employ an afterburner on either a low bypass turbofan or a turbojet. On this page we will discuss some of the fundamentals of an afterburning turbojet . In order for fighter planes to fly faster than sound (supersonic), they have to overcome a sharp rise in drag near the speed of sound. Low bypass ratio turbofans are still more fuel efficient than basic turbojets. Many modern fighter planes actually use low bypass ratio turbofans equipped with afterburners. They can then cruise efficiently but still have high thrust when dogfighting.