Multi-scale recurrence plot analysis of inclined oil-water two phase flow structure based on conductance fluctuation signals

The measurement of flow parameters in inclined oil-water two phase flow system is greatly affected by the complex flow structure. Based on conductance fluctuation signals from the vertical multiple electrode array sensor, the signal characteristic in time and frequency domain are analyzed firstly, then, the recurrence plot texture of inclined water dominated counter flow pattern and transitional flow pattern are studied by multi-scale recurrence plots analysis, and the performance of flow pattern classification based on this method is validated by chaotic attractor morphological description method. The results show that the texture evolvement of multi-scale recurrence plots corresponds to flow pattern transition, especially the complex inclined water dominated oil-water two phase flow structure can be identified from the trend of multi-scale recurrence rate. This study shows that the multi-scale recurrence plots analysis is a valuable tool to characterize the inclined oil-water two phase flow structure.