Comparison of experimental pressure drop data for two phase flows to prediction methods using a general model

In this paper, existing and new two phase pressure drop data are used to run an extensive comparison to predictive methods. The database used is for seven refrigerants (R22, R134a, R404A, R407C, R410A, R417A, and R507A) over a wide range of operating conditions. The procedure used for the comparison is a model of general validity since it is independent of the data reduction procedure. Four quoted methods and a new one by Moreno Quibén and Thome are used. The statistical analysis showed that the methods by Grِnnerud and by Moreno Quibén and Thome are equally the best. Segregating the data by flow regimes and taking into account for the prediction of the data trends, the method by Moreno Quibén and Thome is able to give reliable predictions in all the range of vapour qualities, especially in the regions of the intermittent flow and dry-out.