APPLICATION OF A MAGNETIC FLOWMETER IN VERTICAL TWO-PHASE SLUG FLOWS

摘要

In two-phase flow experiments, liquid velocity and liquid superficial velocity are important parameters for quantifying the characteristics of various flows. Unfortunately, non-intrusive instrumentation for such measurements is not available. Experiments utilizing magnetic flowmeters in two-phase flow measurements have shown that magnetic flowmeters function properly only for bubbly flows. In this research, it is attempted to extend the application of a magnetic flowmeter to measurements of liquid velocity and liquid superficial velocity in the slug flow regime. To accomplish this objective, first, a theoretical investigation was conducted suggesting that information about void fractions and probabilities of Taylor bubbles and liquid slugs is required. This information was successfully obtained with an impedance void-meter. Experiments were performed in a two-phase air-water loop including a 50.8 mm i.d. vertical test section. Based on electromagnetic theory and knowledge of two-phase flow, liquid velocity and liquid superficial velocity were obtained from a magnetic flowmeter operating in the slug flow regime in the vertical test section. The results suggest that this approach is very promising.