Rotational Speed Adjustment of Axial Flow Fans to Maximize Net Power Output for Direct Dry Cooling Generating Units

It is of benefit to the efficiency improvement of direct dry cooling generating units to investigate the operation adjustment approach of axial flow fans. On the basis of a 2×600MW direct dry cooling power plant, thermo-flow performances of the generating units at various wind speeds and directions are obtained by means of CFD method. It is found that an increase in rotational speed of the upwind axial flow fans in the first row will result in a decrease in the net power output. However, it will increase when the rational speed of all axial flow fans except the axial flow fans in the first row is raised. Finally, elevating the rotational speed of all axial flow fans will result in an improvement of net output at low wind speeds but a decrease at high wind speeds