Papers by Author: Xing Feng

Abstract: LNG carrier is seen as high risk and high economy ship. So this paper is concern about strengthening LNG carriers’ safety servicing on board, evaluated risks during this process and finding out and analyzing the risks occurring mechanisms in detail. Furthermore, the LNG releasing process is simulated by numerical models, which provides a numerical method to evaluate LNG releasing consequence. By analyzing explosive boiling occurring mechanism, the decision conditions have been included in this simulation process. By comparing the results, the effects of explosive boiling have been concluded.

Abstract: Based on the evaluation index system of GESAMP and evaluation procedure about mixture mentioned in the Circ.512, the pollution and hazard evaluation model of oil products were established. According to the evaluation results, it can be found that the evaluation model established here is effective. The evaluation model can be used to quantitatively demarcate the pollution and hazard of oil products, which can provide theoretical support for shipping supervision of oil products.

Abstract: The numerical simulation of oil containment by floating boom under wave-current coupling conditions is presented in a companion paper. The present paper focuses on the use of the numerical experimental platform developed by FENG and WU for the prediction of oil containment failure velocity of floating boom under wave-current coupling conditions. Detailed derivation processes about the containment failure velocity formula are provided. The effects of oil parameters, wave parameters and oil boom parameters on oil containment failure velocity receive particular attention, and the influences of some of these parameters such as oil density, boom draft are quantified. The prediction model can provide an economic, convenient method for oil spill response.

Abstract: In accordance with MARPOL convention, reformates and other aromatic oil belong to Oils, and their marine transportation should comply with Convention Annex I. While these goods may contain some NLSs defined in Annex II, and their transportation should comply with Annex II and IBC code. To make a distinction between the goods defined in Annex I and Annex II, the technical instrument and distinction in relevant industries are researched, in the paper the related definitions and present distinction methods in relevant conventions are analyzed, and a modified distinction method is put forward.

Abstract: The numerical experimental platform of oil containment by floating boom under combined wave and current conditions was presented in a companion paper. The present paper focuses on the application of the platform that numerically predicts the relationship between oil containment failure velocity and wave parameters, oil parameters and boom drafts. The effects of oil density and wave parameters on oil containment failure velocity receive particular attention, and the influence of other parameters such as initial oil volume and boom draft are also quantified.

Abstract: Based on the Navier-Stokes equations for viscous, incompressible fluid and analytic relaxation approach, the 2-D numerical wave and current tank of the viscous fluid with constant depth is established, the volume of fluid (VOF) model is used to track the free surface for simulating the oil containment by rigid floating boom under wave and current conditions, and the motion of boom is accomplished by the technique of dynamic mesh. Then the variation of the oil shape under pure current condition, coplanar current condition and counter current condition were numerically studied, the effects of wave parameters on oil shape before boom were analyzed. The computed results are in general agreement with those obtained from previous studies.

Abstract: Aiming at studying liquefied natural gas discharging on water and evaporated natural gas dispersion, based on the Monin-Obukhov similarity theory, using FLUENT to simulate the Coyote series 3 and 5. It is validated that FLUENT simulation results closer to experimental values than SLAB and DEGADIS model simulation results. And it is simulated the NG dispersing on water by setting higher wall heat conduction rate and simulated LNG discharging on ground by using lower LNG evaporation rate. By comparing the results, it is proved that LNG spilling and dispersion on water would get higher volume concentration than which occurs on ground.

Abstract: For the quantitative calculation of the marine ecosystem service value loss caused by the oil spill, the damage assessment standards of marine ecosystem were established here based on the related knowledge of environmentology, ecology, chemistry, ecotoxicology and so on. First, the types of marine ecosystem and their service functions were classified, then the health assessment on the marine ecosystem was conducted by using Index System Method, and the marine ecosystem service function loss rate was calculated by using the sensitivity analysis method. Finally, the marine ecosystem service value loss of polluted sea area was assessed according to the average public value of different marine ecosystems, and the loss caused by the “Tasman Sea” case was calculated by applying the methods above.

Abstract: The influencing factors of sodium sulfate solution physical crystallization attack on cement mortars were investigated through analyzing the changes of macroscopical capability and microstructure of cement mortars in attack process. Results indicate that with partial soaking time increasing, more and more sulfate sodium crystals grow on cement mortars surface, and cement mortars surface is denuded gradually. Compressive and flexural strength increase first and then decrease in the deterioration process. In the attack process, porosity of cement mortars decreases first and then increases. Lots of sodium sulfate crystals accumulate in pores of cement mortars and crystallization pressure is on the rise, resulting in physical crystallization attack taking place.