US Patent 7886772 Noise reducing fluid passageways for fluid flow control devices

Trim disk assemblies for use in fluid flow control devices include a first disk and a second disk. An elongated void is formed in a surface of each of the first disk and the second disk. The second disk is aligned with the first disk to provide fluid communication between the void of the first disk and the void of the second disk, the void of the first disk being offset or staggered from the void of the second disk. The void of the first disk and the void of the second disk at least partially define a fluid passageway having a cross-sectional area characterized by increases and decreases in cross-sectional area, which define an expansion/contraction mechanism of the fluid passageway.