In massive stars, the convection in the interior is different from that of intermediate and small mass stars. In the MS(Main Sequence) phase of small mass stars, there is a convective core and a radiative envelope, between which is the radiative intermediate layers with uneven chemical abundances. Semi-convection would occur in the intermediate layers between the convective core and the homogeneous envelope in massive stars. In the present paper, the Schwarzschild method and the Ledoux method are used to process the semi-convection and core overshooting for $15M_{\bigodot}$ and $30M_{\bigodot}$ stars. Different entropy gradient is used when adopting the Schwarzschild method and the Ledoux method which are used to confine the convective boundary and to calculate the turbulent quantities: $\frac{\partial \overline{s}}{\partial r}=-\frac{c_{p}}{H_P}(\nabla-\nabla_{\rm ad})$ when the Schwarzschild method is adopted and $\frac{\partial \overline{s}}{\partial r}=-\frac{c_{p}}{H_P}(\nabla-\nabla_{\rm ad}-\nabla_{\mu})$ when the Ledoux method is adopted. Core convective overshooting and semi-convection are treated as a whole part and the development of them are found to present nearly opposite tendency, more intensive core convective overshooting lead to weaker semi-convection. The influences of different parameters and the convection processing methods on the turbulent quantities are analyzed in this paper. Increasing the mixing-length parameter $\alpha$ leads to more turbulent dynamic energy in the convective core and prolonging the overshooting distance but depressing the development of semi-convection. The hydrodynamic diffusion process is used to model the convective mixing. In this two processes, we introduce one diffusive parameter D, which is different from other authors introducing different parameters for the two regions. The influences of the turbulent diffusion process on the chemical evolution and other quantities of the stellar structure are shown in the present paper.
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