Hi, how to start a simulation of a mixing tank (batch reactor using Gambit, esp. to generate the grid. One consideration, I don't have experimental data of velocity components. Is there any way I can start the simulation without these data for the boundary conditions?

Try Multiple Reference Frame if your tank using baffles. But it's a little difficult in drawing and then meshing your model. First mesh, try TGRID. if it's success, try the other more uniform grid