Critical impact factors on the cooling performance design of natural draft dry cooling tower and relevant optimization strategies

Because of the inherent water saving merit, natural draft dry cooling towers (NDDCTs) were widely used by power units in arid regions. The cooling performance of NDDCT plays an important role in the economic and safe running of power units. Then, the design of NDDCTs should be optimized from the design stage. Considering the following factors, such as the tower shape, the radiator arrangement, the ambient crosswind, and the mass flow ratio of circulating water to exhausting steam (m), an optimization model was put forward based on theoretical analyses. Through orthogonality analysis, two critical tower shape factors were selected, which were the ratio of the tower height to its bottom diameter and the ratio of the tower throat area to its bottom shell area. Combining the number of cooling column and m, the cooling performance of NDDCTs was optimized and relevant strategies were proposed. Meanwhile, the height of tower was optimized and the minimum construction cost of NDDCT was obtained with optimized cooling performance.