Simplified prediction method for heat transfer performance of air coolers under wet-cooling conditions

 Establishes a new mathematical model of water-cooled air cooler under wet-cooling conditions based on mean surface temperature method and effectiveness-number of heat transfer unit method. The new model predicts the performance with nominal operating parameters only and without complex model setting and algorithm and the geometrical data or detailed performance data of the air cooler. The convective heat transfer coefficients at the water side and the air side are derived from the nominal sensible heat transfer rate. Based on the mathematical model, establishes a wet-cooling condition simulation model of air coolers by Modelica language. Validates the new model by the measured data of an air cooler. The results show that the deviations between the outlet temperature and heat transfer rate predicted by the new model and the measured values are less than 6% and 12% respectively, and the calculation time is only about 10 s in each simulated working condition.