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A new set of equations have been derived from the full
Navier-Stokes equation to describe the radial motion of a gas
bubble in a compressible viscous liquid. These equations include
new terms resulting from considerations of the two coefficients of
viscosity and that of the compressibility of both the liquid and
the gas. Also, the new equations can not be merged into one unlike
all previously derived equations. Numerical calculations have been
performed neglecting the gas viscosity and utilizing the Stockes'
hypothesis $(\lambda=-2\mu/3)$ for the liquid. The results
indicate that the influence of new terms, which are related to the
liquid viscosity, is only remarkable at the end of the collapse,
where the bubble motion is significantly compressible. Also, the
more intense the collapse is, the more prominent are the roles of
these new terms.
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