What is the principle of an aircraft thrust reverser?
2 Answers
Aircraft thrust reversers redirect the expelled engine gases towards the front of the engine, causing the gases to be ejected forward and generating a force opposite to the direction of aircraft flight, known as reverse thrust. The specific working principle is as follows: 1. During normal flight, the clamshell doors are tightly attached to the cascade vanes on both sides of the nozzle, allowing the exhaust gases to flow out of the nozzle to obtain forward thrust. 2. When deceleration is required, the clamshell doors, under the action of hydraulic actuators, block the nozzle passage. The exhaust gases are obstructed by the clamshell doors and are redirected forward at a 45° angle to the axis through the cascade vanes, then ejected diagonally forward through the side exhaust ports, generating a reverse thrust.
I'm particularly fascinated by the principle of aircraft thrust reversers, which are essentially ingenious deceleration devices. When an aircraft lands, the thrust reverser is activated, and this clever mechanism alters the direction of the engine's exhaust. In a jet engine, the fan blades or sleeves move to redirect a portion of the airflow forward instead of backward. As a result, instead of propelling the aircraft forward, the airflow generates a reverse pulling force, aiding in rapid deceleration. Throughout this process, the pilot simply flips a switch in the cockpit, and the system springs into action, significantly reducing the taxiing distance. Especially on wet or slippery runways, it also minimizes brake wear and enhances safety. The design of thrust reversers is highly sophisticated, with different types such as cold stream reversers, which only target the cold air portion, and hot stream reversers, which handle high-temperature exhaust. Each type has its advantages, and their combined use ensures smoother and more reliable landings.
