Torque flow pumps are widely used for pumping of fluids with high content of solid and fibrous inclusions and gas bubbles, in particular, for pumping of sewage and wastes. Fluid flow in these pumps is featured with strong vortex patterns, making it difficult to predict reliably their performance curves numerically. The paper is devoted to selection of a numerical approach for simulation of fluid flow in a torque flow pump of “Turo” type and its influence on simulation results. In particular, influence of geometrical configuration of the rotor-stator interface as well as numerical grid fineness is demonstrated. For one geometric configuration, the fluid flow is simulated with different turbulent models, with a steady state as well as transient approach. The simulations were performed using the software product ANSYS CFX. The simulation results are compared with the experimental measurements in the torque flow pump of “Turo” type. The experimental research included probing of fluid flow in three cross-sections of the stator domain, visualizing of streamlines along the rotating and stationary walls, as well as obtaining of performance curves. A good agreement between the numerical and experimental results is obtained as the rotor-stator interface is located at some distance off the rotating parts. Influence of choice of the turbulence model on the simulation results is demonstrated. Conclusions and recommendations are made concerning the choice of initial and boundary conditions, geometrical configuration of the rotor-stator interface, and parameters of turbulence models that affect both the flow pattern in the pump and its performance curves as well as the numerical solution time and required computational resources.