Stan naprężeń i odkształceń w łopatkach wentylatorów silników elektrycznych

The paper refers to issues connected with damages of fans used in large power inductive motors. Examples of damages of fans are presented (Fig. 1 and 2) as well as their influence on damages of stator windings of a motor (Fig. 3). Analysis of loads acting on fan vanes under transient and steady states is performed. A model has been carried out (Fig. 5) to calculate deformations and stresses in vanes (Fig. 4) of a fan is presented on Fig. 1b using software based on MES. Results of stresses distribution of vanes caused by: centrifugal forces, air resistance as well as angular acceleration (Fig. 6 to 9) are presented. Calculations of free vibration frequency of fan vanes (Fig. 10) were made. The paper ending includes conclusions of analysis of stress state in fan vanes obtained from computer calculations and analysis of damages of fans.