Development of small natural draft dry cooling towers for geothermal power plants

Abstract

Current design methods for natural draft dry cooling tower (NDDCT) do not include the crosswind effect which is unfavorable to the performance of cooling towers. This effect of the crosswind will be even more unfavorable to the performance of small cooling towers since the percentage of the disturbed free air flow is considerably higher than for large NDDCT. Therefore, the validity of the current design methods is questionable for small NDDCT design. Analytical and numerical modeling has been carried to investigate the performance of small NDDCT under different crosswind conditions. The smallest sizes of natural draft cooling towers were derived based on current design methods. The effect of various crosswinds on the performance of small tower is demonstrated with a 3D CFD simulation. Preliminary results showed that the velocity and temperature distributions in the tower have been significantly influenced by the crosswinds