Air–Snow Two-Phase Transport Across the Collection and Throwing Stages of a Rotary Snow Blower: Energy-Efficient Fan Design and Performance Assessment

Snow collection and centrifugal throwing jointly determine the energy demand of rotary snow blowers. Evaluating them separately obscures how upstream loading affects fan and system performance. This study combines vehicle-scale collector experiments with sequential air–snow two-phase simulations. The collector model reproduced outlet snow mass flow with deviations below 3.4%. Three collector conditions at 110, 130, and 150rpm supplied mass flows of 899.2, 884.4, and 855.9kg/s, respectively, to both fan designs. Designs were compared at a common mean snow outlet velocity of 14.93m/s. Orthogonal-array screening identified a five-blade configuration with a −10∘ inclination, a piecewise-linear profile, and a 20mm volute offset. The selected fan reduced fan power by approximately 33.7% at each loading. System power decreased by 30.9%, 29.4%, and 27.5%, while the specific energy fell to 0.262, 0.280, and 0.305kJ/kg, respectively. Flow fields associated the lower power demand with improved outlet guidance and weaker recirculation. These predictions show how matched-performance fan design can reduce collection–throwing energy demand across multiple upstream loadings.