Velocity of acoustical waves in liquid-filled capillary tubes at loiv temperatures

In order to measure the velocity of sound in liquefied gases, contained in capillary tubes at low temperatures, the influence of the wall vibrations and the Kirchhoff-Helmholtz corrections on the velocity of sound in liquid oxygen and nitrogen have been studied.

Firstly the velocity of sound in several liquid filled tubes, with a relative large inner diameter and varying wall thickness, was measured and these experimental results compared with the free space velocity.

The velocity of sound was then measured in liquid filled tubes having a large wall thickness, but varying now the inner diameter of the tubes. After correction of these results for the wall vibrations, we obtained for the velocity of sound, as a function of the diameter of the capillary tube, a curve which agrees reasonably with the theoretical curve calculated from the Kirchhoff-Helmholtz formulae.