Patent ID: 9506422
Filing Date: 2016-11-29
CPC Classification: F01D,F02K,F05D

Claim Text:
1. A gas turbine engine comprising: a spool; a turbine coupled to drive the spool; a propulsor coupled to be driven by said turbine through said spool, said propulsor being located at an inlet of a core flow passage and bypass flow passage having a design pressure ratio that is between 1.3 and 1.4, with regard to an inlet pressure and an outlet pressure of said bypass flow passage, at a design rotational speed of the propulsor, said bypass flow passage defining a bypass ratio of 8.5 to 13.5 with regard to flow through said bypass flow passage and flow through said core flow passage; and a gear assembly coupled between said propulsor and said spool such that rotation of said spool drives said propulsor at a lower speed than said spool, said propulsor being susceptible at said lower speed to propulsive losses from at least one of flow discontinuities, shocks and turbulence, wherein said propulsor includes a hub and a row of propulsor blades that extend from said hub, and said row includes a number (N) of said propulsor blades that is no more than 20, and wherein each of said propulsor blades extends radially between a root and a tip and in a chord direction between a leading edge and a trailing edge at the tip to define a chord dimension (CD), said row of propulsor blades defining a circumferential pitch (CP) with regard to said tips, said row of propulsor blades including a solidity value (R) of CD/CP that is between 1.0 and 1.3 and a ratio of N/R from 9 to 20 to manage said propulsive losses at said lower speed.