Experiment Study On Water Distribution Uniformity And Its Influence On Heat And Mass Transfer Of Closed Circuit Cooling Tower

At present, the contradiction between economic development and the shortage of resources is growing in our country. To achieve the strategic plan of energy conservation and low carbon economy, the new energy saving technology needs to be widely applied in industrial production. As an energy efficient and water-saving heat exchange equipment, there is a widely prospect market of close circuit cooling tower in the context of energy crisis and environmental protection. This paper aimed at the issue of water distribution uniformity in closed circuit cooling tower, based on the structure of water distributor and heat exchange tube, improvement measures were put forward and main content was divided into the following three parts:1. Analysed the method of optimal design for the water distribution device used in closed circuit cooling tower. The distributed performance of three different types spray nozzles was tested.2. A two-dimensional calculation model was built, and with this, the influence of different process water velocity, face velocity, air flow and water flow rate per unit length to the thermal performance was calculated.3. Observed and analysed the water film flows in the circular tube, oval tube and twisted tube, and compared the heat and mass transfer performance between oval tube and twisted tube with experiments. Experiments showed that, in the same condition, the heat transfer of twisted tube was 1.1 to 1.3 times for that of oval tube, and not only the water film heat transfer coefficient of twisted tube was larger than the oval tube, but also the mass transfer coefficient was higher than the oval tube. In addition, the article also been applied to fit heat and mass transfer equation of twisted tube closed circuit cooling tower, the convection heat transfer coefficient of water film air mass flow was a function of temperature and water film, water film and air mass transfer coefficient was a function of the air mass flow.Through this study, a theoretical basis was provided for the water spray uniformity and heat and mass transfer enhancement of closed circuit cooling tower and it would have a guiding role for the optimal design of a noval closed circuit cooling tower.