An Investigation Of The Frictional Pressure Drop Of Air-Water Two-Phase Flow In Vertical Helicoidal Coiled Tube

Spiral heat exchanger has been more widely used in various engineering, but the study of pressure drop of two-phase flow in helicoidal coiled tubes is rare. In this paper, experimental method and numerical modeling method were used to study the pressure drop of two-phase flow:1. In this paper, an empirical correlation about friction factor of air single-phase flow in vertical helicoidal coiled tubes was obtained from our present data,the error was less than 3%.2. In this paper, Fractional pressure drop of air-water two-phase flow was studied in a vertical helical coiled tube. Based on previous studies, a new correlation was obtained from our present data. It could be applied in the situation of low pressure and low mass flow. In the experimental research, respectively, the homogeneous flow model and the separated flow model were used to deal with the results. We found that the homogeneous flow model was not good to deal with the results,and we also found that the L-M model approach, one of separated flow models, was better to deal with the results.3. With the help of numerical modeling method, the friction pressure drop in a helicoidal coiled tube was studied. First, the friction pressure drop of two-phase flow in the helicoidal coiled tube were calculated by the numerical modeling method, the results were similar with the results of experiment, so we believed that the results calculated by the numerical modeling method is creditable. Then based on the previous model, we did further research about the the frictional pressure drop in the helicoidal coiled tube.