Question

Please answer with some detail.

BERIA EERIA Figure 1: photo of an airplane using the reverse thrust to shorten the stopping distance Reverse thrust is a method to shorten the stopping distance on a runway. Vanes built into the turbine reverse the airflow and create a backward thrust slowing the plane down and reducing the distance it needs to come to a full stop. Discuss the forces that are involved to create this thrust by using the concept of control volume and momentum flux for turbine. What is the impact of the angle? Make reasonable assumptions about the variables, e.g. density of air, air speed, friction (can it be neglected?) etc. Engine Reverse thruster Fuselage Figure 2: 2D sketch of airflow through a turbine with reverse thrusters

Answer 1

• In Case of reverse thruster, aircraft is slowed down by reversing or changing direction of momentum of turbine exit gas thus generating backward force on the thruster vanes that at angle with vertical as shown when considering turbine along with vanes as control system. If this angle increases, reverse thrust generated on the vanes increases and becomes maximum when it approaches 180 degrees.

in 7 engine > Freverse 2 F Forward 2 Freverse out le Freverse - Fforward = ma. Control volume 1. Net force,