Results from the Collaborative Computational Project in Wave Structure Interaction (CCP-WSI) Blind Test Series 3 are presented. Participants, with numerical methods, ranging from low-fidelity linear models to high-fidelity Navier-Stokes (NS) solvers, simulate the interaction between focused waves and floating structures without prior access to the physical data. The waves are crest-focused NewWaves with various crest heights. Two structures are considered: a hemispherical-bottomed buoy and a truncated cylinder with a moon-pool; both are taut-moored with one linear spring mooring. To assess the predictive capability of each method, numerical results for heave, surge, pitch and mooring load are compared against corresponding physical data. In general, the NS solvers appear to predict the behaviour of the structures better than the linearised methods but there is considerable variation in the results (even between similar methods). Recommendations are made for future comparative studies and development of numerical modelling standards.

A novel spouted bed, namely, an annular spouted bed with multiple air nozzles, has been proposed for dryness, pyrolysis, and gasification of coal particulates. It consists of two homocentric upright cylinders with some annularly located spouting air nozzles between inner and outer cylinders. Experiments have been performed to study hydrodynamic characteristics of this device. The test materials studied are ash particle, soy bean, and black bean. Three distinct spouting stages have been examined and outlined with the hold-ups increase. In the fully developed spouting stage, three flow behaviors of particles have been observed and delimited. The effects of nozzle mode and spouting velocity on the maximum spouting height of the dense-phase region, spoutable static bed height, and spouting pressure drop in the bed have been investigated experimentally.

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Experimental study on the flow patterns and transitions in a novel annular spouted bed with multiple air nozzles was carried out. Three distinct stable flow patterns, i.e. internal jet, jet-spouting, and fully developed spouting were identified. Two transitional flow patterns and flow instabilities, single internal jet, single jetspouting, and bubbling or slugging were found. Schematic diagrams and typical flow pattern images obtained by a digital charge-coupled display (CCD) camera were presented for classifying these flow patterns. Experimental results show that the internal jet or jet-spouting is easier to occur for forward nozzles than for angle nozzles with the increasing of spouting gas velocity. Due to the interaction of spouting gases from different nozzles, the turbulent exchange or mixing of particles among the nozzles in the fully developed spouting state can be observed distinctly. The total bed pressure drop varied with the spouting gas velocity increases, as a result of the transition of flow pattern. Typical flow pattern map at various static bed heights and spouting gas velocity were plotted for describing the transitions between flow patterns.