Residence-time experiments were used to study the single-phase flow hydrodynamics of a rotor-stator spinning disc reactor. Two reactor setups of different sizes were used to identify the effects of the operating parameters. To precisely determine the central moments of the transfer functions of the reactors, which allow conclusions on the fluid flow profiles in the gap between the moving and nonmoving parts, a deconvolution procedure in the time and frequency domains was established. Residence-time models were compared with regard to their applicability for deconvolution and fitting. The spatial extent of the convectionally back-mixed and the plug-flow regions was quantified with a threshold method. The results were incorporated into an engineering model and compared to literature data.