US 11,927,134 B1
Gas turbine engine having a heat exchanger located in an annular duct
Scott Alan Schimmels, Miamisburg, OH (US); Jeffrey Douglas Rambo, Mason, OH (US); Timothy Richard DePuy, Liberty Township, OH (US); and Steven B. Morris, Mason, OH (US)
Assigned to General Electric Company, Schenectady, NY (US)
Filed by General Electric Company, Schenectady, NY (US)
Filed on Jan. 27, 2023, as Appl. No. 18/160,375.
Int. Cl. F02C 7/12 (2006.01); F01D 25/12 (2006.01); F01D 25/14 (2006.01)
CPC F02C 7/12 (2013.01) [F01D 25/12 (2013.01); F01D 25/14 (2013.01); F05D 2220/323 (2013.01); F05D 2240/14 (2013.01); F05D 2260/213 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A gas turbine engine defining a centerline and a circumferential direction, the gas turbine engine comprising:
a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order;
a rotor assembly driven by the turbomachine and operable at a first blade passing frequency (f1) greater than or equal to 2,500 hertz and less than or equal to 5,000 hertz during a high power operating condition, the rotor assembly, the turbomachine, or both comprising a substantially annular duct relative to the centerline of the gas turbine engine, the substantially annular duct defining a flowpath;
a heat exchanger positioned within the annular duct and extending substantially continuously along the circumferential direction, the heat exchanger comprising a first material defining a heat exchange surface exposed to the flowpath, wherein the first material defines a heat exchange coefficient and wherein the heat exchange surface defines a surface area (A), wherein a product of the heat exchange coefficient and the surface area, UA, is between 7500 British thermal units per hour per degrees Fahrenheit (Btu/(hr-° F.)) and 45000 Btu/(hr-° F.);
wherein an effective transmission loss (ETL) for the heat exchanger positioned within the annular duct is between 5 decibels and 1 decibels for the high power operating condition,
wherein ETL equals

OG Complex Work Unit Math
wherein when the operating condition is the high power operating condition, C1 equals 21.02, C2 equals 0.027, C3 equals 107, and EOC is between 50,347 and 12,587; and
wherein the heat exchanger comprises a heat transfer section defining an acoustic length (Li), and wherein an Operational Acoustic Reduction Ratio (OARR) is greater than or equ al to 0.75, the OARR equal to:

OG Complex Work Unit Math
wherein a1 is equal to 13,200 inches per second during the high power operating condition.