We present multidimensional modeling of convection and oscillations in main-sequence stars somewhat more massive than the Sun, using three separate approaches: 1) Using the 3-D planar StellarBox radiation hydrodynamics code to model the envelope convection zone and part of the radiative zone. Our goals are to examine the interaction of stellar pulsations with turbulent convection in the envelope, excitation of acoustic modes, and the role of convective overshooting; 2) Applying the spherical 3-D MHD ASH (Anelastic Spherical Harmonics) code to simulate the core convection and radiative zone. Our goal is to determine whether core convection can excite low-frequency gravity modes, and thereby explain the presence of low frequencies for some hybrid γ Dor/δ Sct variables for which the envelope convection zone is too shallow for the convective blocking mechanism to drive gravity modes; 3) Applying the ROTORC 2-D stellar evolution and dynamics code to calculate evolution with a variety of initial rotation rates and extents of core convective overshooting. The nonradial adiabatic pulsation frequencies of these nonspherical models are calculated using the 2-D pulsation code NRO. We present new insights into pulsations of 1-2 M⊙ stars gained by multidimensional modeling.

The Rossby number Ro is an important quantity related to the well-known magnetic activity-rotation correlation for main sequence, solar-type stars. For such stars, Ro can be obtained by a semi-empirical relationship between the convective turnover time τc and the B-V colour index, but an equivalent activity-rotation correlation seems not to exist for pre-main sequence stars. In this work we report theoretical estimates of τc for low-mass, rotating pre-main sequence stars under either the Full Spectrum of Turbulence (FST) or the classical Mixing Length Theory (MLT) convection models. The results for the MLT models show that the lower the convection efficiency the higher τc, while the FST models give τc lower than those for the MLT. The presence of a parametric magnetic field lowers the convection efficiency, resulting in smaller τc values.