CENTRIFUGAL FAN IMPELLER Russian patent published in 2002 - IPC

FIELD: military vehicles; cooling system fans. SUBSTANCE: impeller parameters are adapter to conditions of considerable irregularity of velocity field at ventilation plant inlet which is caused by compact layout and blocking up of input by sets of engine-transmission plant of military vehicle. To increase efficiency under said conditions, blade is made with reversed curvature (S-shaped) profile with curvature sign change point located on 0.8-0.95 of impeller diameter and number of blades and their profile are determined basing on condition that relative curvature of blade-to-blade channel axis on section between projections of leading and trailing edges of blade joints should not exceed 4%. Indicated ratios are true for impellers of centrifugal fans with backward-curved blades of military vehicle cooling systems with relative diameter of inlet equal to 0.85 and relative width at outlet equal to 0.2-0.28 of impeller diameter. EFFECT: increased air flow rate, efficiency and strength of impeller without increasing size of ventilation plant. 1 dwg