# Publications

__Lumped Parameter Description of Thermovisous Acoustics in Tubes with Equilateral Triangular Cross-Sections__

An accurate acoustic model of a tube in the millimeter or submillimeter

size should include the losses that occur due to viscosity

and thermal conduction, collectively termed thermoviscous

losses. These losses are prominent in a boundary layer near

the tube walls. Under the assumption that the boundary layer is

thick compared to a characteristic geometry length, such as the

radius for a circular cross-section, and fills out the entire crosssection,

the tube can be described via a lumped parameter model.

The lumped parameters have been known for several decades for

a tube with circular cross-section, but the equilateral triangular

tube has only been investigated in terms of transmission line parameters.

The lumped parameters have here been established for

the equilateral triangular tube as a truncated series solution of

the transmission line parameters. One result observed is that the

lumped parameter model for a triangular tube has 38% more viscous

loss than a circular tube for a given area.