Patent ID: 11927134
Assignee: GENERAL ELECTRIC COMPANY
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 19:
20. 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; and
a heat exchanger positioned within the annular duct and extending substantially continuously along the circumferential direction,
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, 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 equal to 0.75, the OARR equal to:, sin
  ⁢
  
    
  
  ⁢
  
    
      (
      
        
          
            2
            ×
            π
            ×
            
              f
              1
            
          
          
            a
            1
          
        
        ×
        
          L
          i
        
      
      )
    
    2
  

wherein a1 is equal to 13,200 inches per second during the high power operating condition.