Two-Phase Flows in horizontal pipes and manifolds
Horizontal two-phase flows occur in nature and many technological areas, e.g. in pipeline transport and storage tanks. This type of flow is also relevant for compact heat exchangers, which generally consist of a feed tube, header and a large number of parallel micro-channels. For these devices the distribution of the gas and liquid phase to the individual micro-channels highly depends on the flow regime in the feed tube and the header. A uniform flow distribution is favorable for the heat exchanger performance, whereas a non-uniform distribution can lead to freezing, excessive mechanical stresses and reduced service life. As illustrated by this example, there is a need for reliable CFD methods to predict structure of horizontal two-phase flows in industrial applications. Hence, this research work is aimed identifying and modelling of the significant physical mechanisms governing the flow regime transitions and flow distribution in horizontal apparatuses.
Experimental methods are employed to gain validation data and include microfocus x-ray tomography and high-speed videometry. At the same time, the advancement of CFD methods based on the Eulerian multi-field approach is pursued. Building upon the experimental findings, this project focusses on the improvement and extension of the AIAD and GENTOP concepts.