  Context. Continued investigation of the linkage between magneto-acoustic
energy generation in stellar convective zones and the energy dissipation and
radiative emission in outer stellar atmospheres in stars of different activity
levels. Aims. We compute the wave energy fluxes carried by longitudinal tube
waves along vertically oriented thin magnetic fluxes tubes embedded in the
atmospheres of theoretical main-sequence stars based on stellar parameters
deduced by R. L. Kurucz and D. F. Gray. Additionally, we present a fitting
formula for the wave energy flux based on the governing stellar and magnetic
parameters. Methods. A modified theory of turbulence generation based on the
mixing-length concept is combined with the magneto-hydrodynamic equations to
numerically account for the wave energies generated at the base of magnetic
flux tubes. Results. The results indicate a stiff dependence of the generated
wave energy on the stellar and magnetic parameters in principal agreement with
previous studies. The wave energy flux F_LTW decreases by about a factor of 1.7
between G0V and K0V stars, but drops by almost two orders of magnitude between
K0V and M0V stars. In addition, the values for F_LTW are significantly higher
for lower in-tube magnetic field strengths. Both results are consistent with
the findings from previous studies. Conclusions. Our study will add to the
description of magnetic energy generation in late-type main-sequence stars. Our
results will be helpful for calculating theoretical atmospheric models for
stars of different levels of magnetic activity.
