Pattern conversion prediction about low water content water-oil flow based on Terahertz time domain spectroscopy

摘要

This paper aims at presenting an approach for the experimental flow pattern conversion prediction. The water-diesel mixture flowed in the horizontal square tube with water contents of 0, 0.7%, 1.5%, 2.0% and 2.3%, respectively. After the mixture flowed steadily, the sample cell, in horizontal direction, was transmitted by the terahertz radiation and the terahertz time domain spectra were obtained for all the water-diesel mixtures. There is a critical velocity V_T to all of the mixtures. If the flow rate is slower than V_T, the mixtures flow with water bubbly pattern, however, the mixtures will flow with the water foggy pattern and the loss of the THz ray increased rapidly when the rate is faster than V_T. Consequently, the mixture pattern conversion can be predicted by detecting the turning point of the THz ray loss.