variavel0=<b>Luis Gustavo Trapp</b> - gustavo.trapp@embraer.com.br EMBRAER S/A - Empresa Brasileira de Aeronáutica
<b>Guilherme Lara Oliveira</b> - guilherme.oliveira@embraer.com.br EMBRAER
<b>Abstract.</b> The design of reverser systems tries to maximize the reverser thrust available. This objective is limited by several restrictions, namely: reingestion of the engine reversed gases by its own inlet affecting engine’s operation; loss of efficiency of the aircraft control surfaces and spoilers; deterioration of wing and fuselage due to reverser jet impingement; and aircraft instability due to buoyancy effects on the fuselage. Latest reverser systems design favors blocking only the fan flow and directing it to the desired location through the use of cascades, which can locally orient the flow and avoid it from reaching undesirable places. In this work three different cascade configurations being considered to equip the new Embraer Jet (EMB 170) were simulated through CFD (Computational Fluid Dynamics). The main objective was to anticipate if any of these configurations would cause problems to the aircraft. If the results were shown to be acceptable they would be later evaluated during ground and flight test campaign. It was used a half model mesh of a full aircraft in landing configuration with reverser, flaps, slats, spoilers and landing gears deployed, the ground was considered as well. The half model numerical mesh has 1.4 million tetrahedral elements. A commercial CFD software was used with a density based coupled solver and realizable k-e turbulence model. This numerical approach was shown to be a very cost effective way of testing many different reverser cascade configurations reducing inherent flight test risks. Understanding how the aircraft is affected by the thrust reverser allowed a better design of the aircraft test campaign and also increased aircraft testing safety since the reverser efflux patterns were understood and test pilots warned about any controllability issues they could face.
<b>Keywords.</b> Aircraft, Engine, Propulsion, Thrust Reverser, CFD.