Experiment Study on Heat Transfer and Flow Characteristics in Micro-wavy Tubes

The heat transfer and flow characteristics of three micro-wavy tubes with different configuration parameters were considered by using single phase water as working medium. The temperature and flow rate of hot water at constant value were kept while changing the temperature and flow rate of cool water during the experiments. The results of experiments show that the heat transfer performance of the micro-wavy tubes is much higher than that of straight tubes．At Re <10 000 region, the Nu of the three micro-wave tubes increases by 111.5%, 166.7% and 101.4%, compared with that of straight tubes, respectively, while the friction coefficient f increases by 95.1%, 96.3% and 67.5%. At Re >10 000 region, the Nu and f of the microwavy tubes increase by 32.6%, 70.6%, 61.2% and 17.8%, 18.1%, 12.6%, respectively.