论文部分内容阅读
建立湖泊三角洲数学模型,对陆相油气田的勘探与开发工作具有重要意义。在湖泊三角洲模型中,假定河床横剖面为矩形,将河口比拟为一个水动力学上的喷咀,河水入湖形成自由射流。由于多数天然河流下游均呈开放性,所以,入湖后流向中心线纵剖面上的流动可以看作二维平面射流。将求得的中心纵剖面上沿河流向速度分量做为求解水平二维平面射流的边界条件,就可得到沿河宽方向速度分量和沿河流流向的速度分量。如果把河流携带的碎屑物看作理想颗粒,则就可采用与弹道式导弹相同的跟踪方法,求出不同河湖水动力条件下三角洲边界、纵剖面形态和沉积物分选性变化。用数学模型揭示湖泊三角洲特征,可以作为研究现代、古代三角洲的借鉴。
The establishment of the mathematical model of the lake delta is of great significance to the exploration and development of continental oil and gas fields. In the delta model of the lake, assuming that the cross section of the riverbed is rectangular and the estuary is compared to a hydrodynamic nozzle, the river enters the lake to form a free jet. Since most of the natural rivers are open to the lower reaches of the river, the flow to the longitudinal centerline after entering the lake can be regarded as a two-dimensional plane jet. The obtained velocity component along the river in the central longitudinal section is taken as the boundary condition for solving the horizontal two-dimensional planar jet, and the velocity component along the width of the river and the velocity component along the river can be obtained. If the debris carried by the river is considered as ideal particles, the same tracking method as the ballistic missile can be used to determine the delta boundary, longitudinal profile and sediment change under different hydrodynamic conditions. Using mathematical models to reveal the characteristics of the lake delta can be used as a reference for studying the modern and ancient delta.