Fluidic Injection Thrust Reverser System for High Bypass Ratio Turbofan Engines: Experimental Model

Conventional thrust reversers involve the usage of mechanical blockers which are bulky as they are designed to sustain heavy loads. As a result, they account for 30% of the nacelle weight (excluding the engine core). This added engine weight results in a 0.5%–1% increase in the specific fuel consumption of the aircraft. This paper advances our investigation of “Blockerless Engine Thrust Reversers” and uses it as an inspiration to optimize the system by designing an injection module (depicting an injection as a bleed from the core flow), conducting a computational analysis and demonstrating the viability of the process by building an experimental model of a 1:40 scale of a GE90 - 115B engine. A 3D printed experimental model was built after conducting an extensive parametric analysis. This model is used to demonstrate the viability of the “Fluidic Injection Thrust Reverser” (FITR) qualitatively and quantitatively.

Inviscid, Axisymmetric, Annular Wall Jet Impingement As an Idealization of Cascade Thrust Reversers

An analytical solution to inviscid, axisymmetric, impinging wall jet flow is proposed as a limited idealization of internal flow within a cascade thrust reverser of an aircraft engine. Behavior of prior Bessel Series solution for round jets is critically examined, before extending the formulation to an annular jet with non-zero inner wall radius. Behavior and accuracy of prior spectral and finite difference algorithms are examined, leading to an efficient hybrid computational scheme. Jet inflow velocity profile has a deficit as well as non-zero vorticity-function at the inner radial boundary, as is typical in engine fan ducts. Inviscid recirculation appears at the impingement corner, the strength of which is made determinate by assuming locally constant vorticity-function. Results indicate that fan duct velocity profile deficit is a significant contributor to occurrence of a large recirculation zone that is experimentally observed within a fully deployed thrust reverser.