Numerical study on the cooling performance of natural draft dry cooling tower with vertical delta radiators under constant heat load

From the view of cooling system, the natural draft dry cooling tower with vertical delta radiators (NDDCTV) under constant heat load can be studied by keeping constant water temperature drop Δtw. With computed entry water temperature tw1 as the sum of tower exit water temperature tw2 and the constant Δtw, a three-dimensional (3D) numerical model for NDDCTV under constant heat load was established. Through analyses about mesh-independence, sensitivity about crosswind profile index and comparison with published results, the accuracy and credibility of the established numerical model for NDDCTV were confirmed. The aerodynamic field around cooling deltas was analyzed at windless and crosswind conditions, so as to clarify the impacts of ambient air temperature and air inflow deviation angle θd on the performance of cooling columns. With constant heat load and uniform entry water temperature, the cooling performance of each sector was analyzed under crosswind impact. With increasing crosswind velocity vc, the cooling performance of NDDCTV under constant heat load deteriorates sharply at low vc, but varies slightly at high vc, which can be improved by air deflectors.