US 12,012,898 B2
Gas turbine engine with acoustic spacing of the fan blades and outlet guide vanes
Brandon Wayne Miller, Evendale, OH (US); Egbert Geertsema, Evendale, OH (US); Arthur W. Sibbach, Boxford, MA (US); Andrew Hudecki, Evendale, OH (US); Timothy Richard DePuy, Evendale, OH (US); John C. Schilling, Evendale, OH (US); Frank Worthoff, Evendale, OH (US); and Tsuguji Nakano, Evendale, OH (US)
Assigned to General Electric Company, Schenectady, NY (US)
Filed by General Electric Company, Schenectady, NY (US)
Filed on Nov. 3, 2022, as Appl. No. 17/979,992.
Prior Publication US 2024/0151185 A1, May 9, 2024
Int. Cl. F02C 7/24 (2006.01); F02C 7/36 (2006.01)
CPC F02C 7/24 (2013.01) [F02C 7/36 (2013.01); F05D 2260/96 (2013.01)] 33 Claims
OG exemplary drawing
 
1. A gas turbine engine comprising:
a core turbine engine comprising a low pressure turbine;
a gearbox assembly coupled to the low pressure turbine;
a fan coupled to the gearbox assembly and having a fan diameter and a plurality of fan blades with a blade solidity that is greater than or equal to 0.8 and less than or equal to 2.0;
a blade effective acoustic length (BEAL) defined as:

OG Complex Work Unit Math
wherein c is a chord length of a fan blade of the plurality of fan blades, S is a span of the fan blade, rr is a radius ratio of the fan, γ is a stagger angle of the fan blade, and Nb is the number of the plurality of fan blades;
a fan case that surrounds the fan, the fan case comprising an inlet disposed forward of the fan and an inlet length, wherein the inlet length defines an average distance from the inlet to the fan;
a plurality of outlet guide vanes disposed aft of the fan and extending radially between the core turbine engine and the fan case;
an acoustic spacing from the fan blade trailing edge to an outlet guide vane leading edge;
an acoustic spacing ratio (ASR) defined as:

OG Complex Work Unit Math
wherein As is the acoustic spacing, Nv is the number of the plurality of outlet guide vanes, and
wherein the ASR of the gas turbine engine is 1.4 to 3.2.