  Artificially increasing the luminosity and the thermal diffusivity of a model
is a common tactic adopted in hydrodynamical simulations of stellar convection.
In this work, we analyse the impact of these artificial modifications on the
physical properties of stellar interiors and specifically on internal gravity
waves. We perform two-dimensional simulations of solar-like stars with the
MUSIC code. We compare three models with different luminosity enhancement
factors to a reference model. The results confirm that properties of the waves
are impacted by the artificial enhancement of the luminosity and thermal
diffusivity. We find that an increase in the stellar luminosity yields a
decrease in the bulk convective turnover timescale and an increase in the
characteristic frequency of excitation of the internal waves. We also show that
a higher energy input in a model, corresponding to a larger luminosity, results
in higher energy in high frequency waves. Across our tests with the luminosity
and thermal diffusivity enhanced together by up to a factor of 104, our results
are consistent with theoretical predictions of radiative damping. Increasing
the luminosity also has an impact on the amplitude of oscillatory motions
across the convective boundary. One must use caution when interpreting studies
of internal gravity waves based on hydrodynamical simulations with artificially
enhanced luminosity.
