Importance

Loading Importance Indicators...

Abstract

A gas turbine engine comprises a fan rotor having blades with an outer diameter. The outer diameter is greater than or equal to 77 inches (196 centimeters) and less than or equal to 135 inches (343 centimeter). The fan rotor has less than or equal to 26 fan blades, and is driven by a fan drive turbine through a gear reduction. The gear reduction has a gear ratio of greater than 2.6:1. The fan rotor delivers air into a bypass duct as bypass air, and into a duct leading to a compressor rotor as core air. A ratio of bypass air to the core air is greater than or equal to 12:1. An upstream turbine rotor is upstream of the fan drive turbine and drives a compressor rotor. The upstream turbine rotor has at least two stages, and the fan drive turbine rotor has at least three stages. The turbine blades in at least one stage of the fan drive turbine rotor are provided with a performance enhancing feature, which is at least one of the blades being manufactured by a directionally solidified blade material. The blades are provided as single crystal blades, and have a radially outer platform provided with scalloping to reduce the weight of the blades. The blades are provided with cooling air.

Loading the Abstract Image...

First Claim