海上退役石油平台造礁的流场效应研究

Investigation of flow field effects of reefing with decommissioned offshore oil platforms

将海上石油平台改建为人工鱼礁是一种理想的退役平台处置方式,流场对人工鱼礁发挥功效起着重要作用,而目前对平台造礁的流场效应仍有待研究。基于埕岛油田退役平台造礁示范工程,构建了渤海埕岛油田海域三维水动力数值模型,在实际海况条件下定量研究不同规模平台造礁对流场影响效应。结果表明:当布设鱼礁山后,在鱼礁山两侧及上方沿水平来流方向均形成流速增大区域,而迎流面和背流面出现了流速减小区域;与无鱼礁山时相比,随着鱼礁山高度增加和来流速度增大,鱼礁山区域流速变化幅度和变化区域面积逐渐增大,且鱼礁山高度对流速影响范围更大,来流速度则决定流速变化幅度;在垂向上会产生明显的上升流与背涡流,随着水平来流速度增大,鱼礁山高度对垂向流场的影响程度逐渐减小。

The conversion of decommissioned offshore oil platforms into artificial reefs offers an effective solution for their disposal.The flow field plays a crucial role in determining the effectiveness of these artificial reefs.However,the impact of the flow field on platform reefing requires further investigation.In this study,we present a three-dimensional hydrodynamic numerical model of the Chengdao oilfield in the Bohai Sea,where a reefing demonstration project for decommissioned platforms was conducted.The model allows for a quantitative analysis of the flow field effects on platforms of different scales under actual sea conditions.The findings reveal that reefing leads to increased flow velocity on both sides and above the reef in the direction of the horizontal incoming current.Conversely,the flow velocity decreases on the headwater and backwater sides.As the reef height and incoming current velocity increase,the magnitude of flow velocity changes and the affected area gradually expand.Moreover,the height of the reef exerts a greater influence on the flow velocity,while the incoming current velocity determines the extent of velocity change.In the vertical direction,noticeable upward flow and back eddy flow are observed,with the impact of the reef height on the vertical flow field diminishing as the horizontal incoming velocity increases.