The generation of internal waves in the radiatively stable stellar region by the turbulent motion at the boundary of the overlaying convective zone is similar to the same case in the deep ocean or in the earth atmosphere (Townsend, 1965), and can be described in a simple way as following: When an turbulent fluid element arrives at the boundary of the convective region with a non-zero momentum, it beats and it deforms the interface between both regions. This disturbance of the equilibrium state excites a train of internal waves propagating below the convective zone in the horizontal and vertical directions for the frequencies lower than the characteristic one for the stable stratification (Brunt-Väisälä frequency).