Experimental Investigation of Flow Noise in a Circular Expansion Using PIV and Acoustic Measurements

Large Eddy Simulation of a Muffler with the High-Order Spectral Difference Method

“…After the flow field was fully developed, time averaging is performed for a period corresponding to about 25 flow-through times. The computation is validated on the center plane of the expansion coinciding with the center planes of the inlet and outlet pipes using the PIV results from [17]. All of the measurements are taken on the symmetrical center plane of the muffler.…”

“…The main purpose of this section is to evaluate the accuracy and the reliability of the fourthorder SD-LES solver for simulating a 3D turbulent flow in an industrial-type muffler. The results are compared with the particle image velocimetry (PIV) measurement performed at the Department of Environmental and Applied Fluid Dynamics of the von Karman Institute for Fluid Dynamics [17]. In Figure 1, the geometry of the muffler and its characteristic dimensions are illustrated, where the flow is from left to right.…”

“…The computation is validated on the center plane of the expansion coinciding with the center planes of the inlet and outlet pipes using the PIV results from [17]. All of the measurements are taken on the symmetrical center plane of the muffler.…”

“…Figure 3: Reynolds stress u ′ 2 u ′ 3 /u 2 max in the axial direction at four cross sections in the expansion chamber, obtained with fourth-order (p = 3) SD-LES method. Comparison with experimental measurements (PIV) [17]. are gratefully acknowledged.…”

“…Figure2: Time-averaged velocity profile in the axial direction ũ3 /u max at four cross sections in the expansion chamber, obtained with fourth-order (p = 3) SD-LES method. Comparison with experimental measurements (PIV)[17].…”