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Liaodong Bay is located at the northern part of the Bohai Sea. There are four blocks where oil and gas are found. In order to exploit these resources in these connected four blocks, extreme value statistics is used to estimate the storm-surge design parameters. Long-term series of storm surge are hindcast by numerical models. Using data from series of extreme storm surge caused by tropical cyclones in the Liaodong Bay, statistical analysis of extreme storm surge is carried out with Poisson-generalized extreme value distribution by considering the occurrence frequencies of tropical cyclones. The 100-year return storm surge is 195cm and the 50-year storm surge is 164cm. Both of them occur in Block 1. Due to the influence of topography of the total four blocks, the intensity trends of storm surges in Blocks 1, 2 and 3 are similar, whereas the intensity of storm surge in Block 4 is relatively small. These results are reference for the structural design in these blocks.

The phase distributions and mechanical properties of annular flow are constantly fluctuating, so they can be regarded as random states. The probability analysis of annular flow is an appropriate method to research the formation, development and evolution of the flow pattern. In the present work, the atomization and deposition rates of fully developed annular flow are investigated in detail by the method of a probability analysis. First, the basic equations of the probability model are applied to solve some important intermediate parameters of annular flow. Second, the atomization and deposition rates of any size droplets are closely related to the probabilities of droplet generation and disappearance. Third, the interchange rate of the whole liquid phase can be obtained by summing the generation and disappearance probabilities of arbitrary size droplets. The predictions of atomization rate are well verified by comparing with the experimental date of 71 cases from three sets of tests. It is demonstrated that the probability model can accurately calculate the atomization rate of the fully developed annular flow for most cases. The predicted deviation for some cases may be caused by the neglect of droplet breakup process. Furthermore, the effects on the atomization rate of seven parameters of annular flow are discussed in detail.

Strong wind often raises waves and result in the sediment siltation. The navigation of outside waterway of Huanghua Port is seriously influenced by sudden siltation induced by strong wind. Before outside waterway treatment, the return sudden siltation volumes must be determined previously. The point estimation of return values can be obtained by distribution curve fitting, meanwhile, interval estimation can provide ranges of return values under some fix confidence levels. Based on the sequences of annual maximum sudden siltation of Huanghua Port from 1979 to 2003, and by using curve fittings of lognormal distribution and maximum entropy distribution, and maximum likelihood interval estimation method, the point and interval estimations of return sudden siltation volumes are presented. The results given by the maximum entropy distribution have higher precision, so they can be applied as the reference of the treatment of sediment accumulation.

Co-occurrence probability analysis of sea ice between adjacent areas is very helpful for the hazard prevention and protection strategy making of coastal and offshore engineering. Yingkou and Huludao with similar latitudes are located on the opposite sides of Liaodong Bay of China. Their sea ice conditions are both apparent in winter and early spring, so it is useful to study on the co-occurrence situations of sea ice conditions between these two areas. Based on the annual maximum sea ice thickness of Yingkou and Huludao observation stations, the co-occurrence probability analysis of sea ice thickness is conducted. The joint probability distributions of sea ice thickness between these adjacent areas are constructed by using univariate maximum entropy distributions and four bivariate copulas. Both marginal curve fittings are very well, and the model determined by Gumbel-Hougaard copula describes the bivariate sea ice thickness data best. Then different cases of co-occurrence probabilities of sea ice thickness between Yingkou and Huludao are presented, and they can provide references to the hazard protection of the coastal and offshore structures between these two areas.

Solid particle erosion in piping systems is a serious concern of integrity management in the oil and gas production, which has been widely predicted by the numerical simulation method. In the present work, every step of the comprehensive procedure is verified when applied to predicting the bend erosion for gas flow, and improvements are made by comparing different computational models. Firstly, five turbulent models are implemented to model the flow field in a 90 degree bend for gas flow and examined by the static pressure and velocity profile measured in experiments. Secondly, the particle velocities calculated by fully coupling and one-way coupling are compared with experimental data. Finally, based on the knowledge of flow modeling and particle tracking, four classic erosion equations are introduced to calculate the penetration rates in a 90 degree bend. By comparing with the experimental data available in the literature, it indicates that the k–e model is the most accurate and effective turbulent model for gas pipe flow; the fully coupling makes the simulation of particle motion closer to measured data; and the Grant and Tabakoff equation presents better performance than other equations.Copyright © 2014 by ASME