**11. Geometry, grid, and boundary conditions**

The configuration of the grids for each stirring model (ROT, MRF, and SM) is shown in **Table 4**. A non-structured grid was adapted to generate tetrahedral and hybrid volumes (Tet/ Hybrid).


**Table 4.** Grid parameters for ROT, MRF, and SM models.

The geometry generated in Gambit® is presented in **Figure 5**. Zone A was defined as the stirred region, while zone B as the stationary region.

**Figure 5.** Isometric: stationary volume (A) and stirred volume (B).

The boundary conditions were defined as "walls" for the impeller and the reactor surfaces, which implies a no-slip condition. On the top face of the reactor, a zero-shear stress boundary condition was established, implying a free fluid movement. Region A was defined as "interior" during SM and MRF simulations. Only for SM an "interface" was defined in the boundary between the stirred and stationary volumes.

Using the original geometry, the effect of resized grid cells (M400k and M200k) on the mathemat‐ ical simulation was analyzed through the velocity variation over a defined position within the reactor; such results are presented in **Figure 6**.

**Figure 6.** Radial velocity comparison between grids M400k and M200k.

**Model ROT MRF SM** Cells 381,352 201,927 Faces 783,158 439,109 Nodes 75,560 40,052

Fluid regions 1 2

) 3757.353 3758.577

The geometry generated in Gambit® is presented in **Figure 5**. Zone A was defined as the stirred

The boundary conditions were defined as "walls" for the impeller and the reactor surfaces, which implies a no-slip condition. On the top face of the reactor, a zero-shear stress boundary condition was established, implying a free fluid movement. Region A was defined as "interior" during SM and MRF simulations. Only for SM an "interface" was defined in the boundary

Using the original geometry, the effect of resized grid cells (M400k and M200k) on the mathemat‐ ical simulation was analyzed through the velocity variation over a defined position within the

Volume elements Mixed

280 Modeling and Simulation in Engineering Sciences

**Table 4.** Grid parameters for ROT, MRF, and SM models.

region, while zone B as the stationary region.

**Figure 5.** Isometric: stationary volume (A) and stirred volume (B).

between the stirred and stationary volumes.

reactor; such results are presented in **Figure 6**.

Volume (cm3

Elements in face Triangular and quadrilaterals
