Comparing measured with calculated multiphase flow pressure drop

Nearly all correlations used to describe multiphase flow systems are based on data obtained from experiments on air-liquid flows in small pipelines. For example, the pressure drop and drag reduction work reported by Otten and Fayed was done with a 1-in. diameter pipe. When such correlations are used to simulate the performance of multiphase flow gathering systems in the oil and gas area, they are frequently extended beyond the range of conditions from which they were developed. It is therefore not surprising that experience has shown that the accuracy of the correlations varies from system to system.