Measurement of oil-water flows in deviated pipes using thermal anemometry and optical probes
Two phase flow investigations have been undertaken for some time involving either liquid-gas or liquid-liquid flows. In spite of the growing interest in inclined (deviated) oil-water flows, only a small number of experimental data exist. This thesis describes an experimental study into deviated oil-water flows using thermal anemometry and optical probes. Two novel measuring techniques have been designed and tested in a 78mm diameter multiphase flow ioop. The measuring devices are known as the dual probe and the dual split-film probe. The dual probe is a combination of a hot-film anemometer and two optical probes. One of the optical probes was used to simplify the analysis of hot-film signals. The dual split-film probe is similar to the dual probe except that it uses a split-film anemometer instead of a hot-film anemometer. The dual probe and the dual split-film probe are both capable of measuring, locally at the same time, the continuous phase velocity, the dispersed phase velocity and the volume fraction. The results from testing the dual probe were satisfactory except when used to measure the water velocity in deviated flow. The hot-film anemometer was not capable of measuring back flows which can be encountered on the bottom part of pipes. The dual split-film probe was successfully tested in deviated flows and was capable of measuring back flows. Local slip velocities and droplet cut chord length profiles were investigated. It was shown that as the oil volume fraction increases, the slip velocity decreases, for all flow conditions investigated. The droplet cut chord length was seen to vary from 2 - 4mm in vertical flow; however in deviated flow, the droplet cut chord length remained constant at approximately 5mm, in regions where oil was present. As a part of the continuing research into deviated oil-water flows, the data gathered were compared to a two phase model with some success. Both the dual probe and the dual split-film probe are patented by Schiumberger Cambridge Research (Simonian ).