What is the difference between direct air cooling and indirect air cooling in thermal power plants?

I've done both. Both direct air cooling and indirect air cooling are cooling methods for circulating water. Direct air cooling adopts air cooling island, and cooling is carried out by large fan and cooling surface of air cooling island. You can look at Suzhou electric field. Indirect air cooling is through indirect cooling tower (similar to the shape and style of cooling tower). There is a cold triangle around the lower part of the cooling tower, which is cooled by indirect air convection inside and outside the cooling tower. You can look at the map of Shaanxi Qinling Electric Field 60,000 stations.