GEnx

Visão geral

The GEnx (General Electric Next-generation eXperience) é o sucessor da GE Aerospace ao CF6 for the fuselagem larga market, developed concurrently for two very different aircraft: the Boeing 787 Dreamliner and the Boeing 747-8. Two distinct variants — GEnx-1B for the 787 and GEnx-2B for the 747-8 — share a common high-pressure core but differ significativamente in their fan, compressor de baixa pressão, and turbine configurations to match each aircraft's thrust and airflow requirements. The GEnx delivers aproximadamente 15% melhor consumo de combustível que o CF6-80C2 que substitui, driven by a higher OPR of 50:1, elevated turbine entry temperatures, and extensive use of composite materials throughout.

A landmark innovation on the GEnx is its composite fan case — the first on a large commercial engine. Combined with pás de fan compostas (18 per engine on the GEnx-1B, 22 on the GEnx-2B), the GEnx achieves significant weight reduction compared to its CF6 predecessor. The engine also incorporates a twin-annular premixing swirler (TAPS) combustor that reduces NOx emissions by aproximadamente 50% compared to CAEP/6 standards, and a 5-stage turbina de baixa pressão using advanced airfoil profiles. The 787's totalmente elétrica architecture enabled GE to eliminate the engine ar sangrado system on the GEnx-1B, simplifying the engine and improving efficiency.

Especificações técnicas

Variantes

The GEnx-1B family powers the 787, with thrust ratings from 53,000 lbf (GEnx-1B54) through 76,100 lbf (GEnx-1B76A). The GEnx-1B64 and -1B67 are the primary variants for the 787-8, while the -1B70/P2, -1B74, and -1B76 serve the larger 787-9 and 787-10. The no-bleed architecture of the 787 required significant GEnx-1B redesign effort compared to conventional engines. The GEnx-2B powers the 747-8 with thrust around 66,500 lbf (GEnx-2B67); unlike the -1B, the -2B retains ar sangrado extraction for the 747-8's conventional pneumatic systems, and uses a larger fan and different LP system. The -2B has also been selected for the 747-8F freighter variant, supporting the cargo operations of UPS and other freight carriers.

Aplicações em aeronaves

• Boeing 787-8: GEnx-1B64/67 (64,000–67,000 lbf) — variante de lançamento do Dreamliner, competindo com Trent 1000
• Boeing 787-9: GEnx-1B70/74/76 (70,000–76,100 lbf) — Dreamliner alongado, variante do 787 mais vendida
• Boeing 787-10: GEnx-1B76A (76,100 lbf) — 787 mais longo, variante de alto empuxo
• Boeing 747-8I: GEnx-2B67 (66,500 lbf) — variante de passageiros Intercontinental; also powers 747-8F freighter

História do desenvolvimento

GE launched the GEnx in 2004 alongside Boeing's 787 program announcement. The first GEnx-1B engine test ran in February 2006 at Peebles. FAA certification of the GEnx-1B was achieved in July 2011, followed by GEnx-2B certification in August 2011. All Nippon Airways operated the first GEnx-powered 787-8 voo comercial in October 2011. An early service issue emerged in 2013 when some 787 operators experienced ice crystal icing in the engine's core at high altitudes, causing power rollbacks — a condition remedied through software and hardware modifications by 2014. The GEnx-2B entered service on the 747-8F with Cargolux in October 2011, and the passenger 747-8I with Lufthansa in June 2012. By 2024, GEnx had accumulated more than 90 million horas de voo and achieved visita à oficina intervals exceeding 25,000 hours on mature engines, comparable to the exceptional CF6 reliability record it was designed to surpass.