Experimental and numerical investigation of transmission loss in a zero-flow silencer
To evaluate the acoustic performance of the muffler at zero flow, different methods of determining transmission loss (TL) were studied. Numerical and experimental approaches were used to calculate TL. The numerical method employed was the Herschel-Quincke tube method (case 1) COMSOL simulation (case 2) and ANSYS simulation (case 3). The experimental approach utilized the transfer matrix method with the aid of software developed by the B&K software (case 4) and the sound card with MATLAB software (case 5) was used to calculate TL. Furthermore, the mesh independence of numerical methods and the uncertainty of the experimental method were examined. Results were evaluated between 20 and 1900 Hz, which is an appropriate frequency range for TL calculations According to the results, the equivalent TL for cases 1 to 5 is approximately 5.81 dB, 5.35 dB, 5.21 dB, 4.08 dB, and 3.77 dB, respectively. Based on the findings, it can be concluded that the equivalent TL of ANSYS and COMSOL simulations was similar, and COMSOL simulation results in an 8% lower equivalent TL than the case 1 approach. Similarly, the equivalent TL of experimental calculation methods indicates that the case 5 approach has a 7.5% lower equivalent TL than the case 4 approach