Experiments with "Constrained Layer Damping" of Small Bore Connections

[yamoffathoo]

A British Firm (GL Industrial Services UK Ltd.) was experimenting with composites to dampen the dynamic response of small bore connections to compressors with the handle "Constrained Layer Damping".
This investigation was completed in 2019, but the Final Summary Report is a little sparce on details, claiming 50% reduction in dynamic stress levels.
Is there anyone out there doing similar work ?

 

[GregLocock]

CLD is widely used in automotive. One example is on brake pads. To reduce squeal a layer of black goo (bitumen possibly) goes on the back of the pad with a steel shim over it.

I'd estimate 90% reduction in noise. The sandwich construction is necessary to develop shear in the goo.