Evaluating vaporization heat, thermal performance, and efficiency of a natural draft wet cooling tower

Abstract

This study aimed to improve the accuracy of the thermal performance analysis of a natural draft wet cooling tower (NDWCT) and explore the effect factors of the decrease water and energy consumption. In this study, we determined the thermal performance and water loss of the NDWCT under dynamic conditions using mass-balance equations, and obtained water loss from 10.4 kg s−1 to 16.9 kg s−1. The analyzed vaporization heat accounted for 71.5%–86.9% of the total heat flow. Furthermore, the total amount of water discharged exceeded the average standard is 33.06 m3 has been spotted for the first time. Increasing the air-water ratio from 0.38 to 0.77, the cooling efficiency is increased by 44%. The change relationship between water temperature drop, water loss, air enthalpy, and air flow in the tower were discovered and established. The thermal performance analysis model based on water loss and air flow was used, compared with the total heat of the measured data, the maximum deviations were by 4.5% and 1.88%, respectively. The validity of the model was fully verified. These two models were combined with the heat balance equation analysis model based on three variables, which can provide support for optimal operation conditions that the energy savings and water reductions in NDWCTs, and providing convenience and a new reference for thermal performance evaluation, design, and research. Finally, we also proposed the suggestion for improving low efficiency of cooling tower is the most economical operation mode.