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Computational Fluid Dynamics (CFD) is a mathematical tool capable of simulating a wide range of fluid flows. Integrated CFD software has been applied to study the flows in two-and three-phase oilfield separators. The influence of inlet nozzle configuration, flow distributors, perforated plates, and outlet nozzles have been studied. Of particular value has been the ability to simulate wave induced sloshing in vessels mounted on floating platforms. The design and placement of baffles to mitigate liquid sloshing was determined by using CFD to simulate fluid flows in vessels destined for service on floating platforms. The simulations accounted for the movement of the vessel based upon its actual location on the platform and identified the influence of process fluid flows on slosh motion. Where possible, laboratory testing has been used to validate CFD simulation results, leading to increased confidence in the mathematical models.

Two new Free Water Knockout (FWKO) vessels were installed on an FPSO facility operating offshore Cabinda, Angola. They were installed to accommodate larger slugs and to debottleneck downstream facilities to cope with increasing water production. The paper describes process design and CFD work for placement of internal baffles to mitigate fluid sloshing in the new separators. Three CFD simulations were performed. First we demonstrated that the separator would not operate properly without custom-designed internal baffles. The second simulation demonstrated that customized baffles in the new vessel could suppress sloshing and prevent water spill over into the oil discharge stream. The final simulation showed that the advanced baffle arrangement would control the problems due to sloshing when fluid flow was introduced into the simulation. Field data is presented to confirm the validity of the simulation work and successful operation of the separators. The work gives confidence in the use of CFD to design separators with minimum weight and size. We show that for critical applications, the CFD design should be applied to the particular case -baffle designs are not "one-size-fits-all".

In this paper, a new block-based pixel domain distributed video coding scheme featured with variable block modes is proposed. In addition to intra mode and Wyner-Ziv mode employed in conventional block-based distributed video coding scheme, two supplementary block modes "SKIP mode" and "zero motion mode" are introduced in the proposed scheme to improve the overall coding efficiency, as well as to reduce the decoding complexity. Moreover, the channel coding is performed on macroblcok level to reduce the coding loss due to inserted information in the parity bits. The simulation results show that the proposed scheme outperforms both the conventional frame-based transform-domain and the blockbased pixel-domain distributed coding schemes.