Abstract It is necessary to accurately predict the diffusion and deposition range of a large amount of sand dumped from a hopper barge for efficient reclamation in a coastal area. Many previous studies have proposed useful models to simulate the diffusion behavior of sand in fluid; however, most of their models have not considered the deposition of sand. This study proposes a particle-based numerical model that includes fluid-sand interaction. The model utilizes two methods to track the sand: an elastoplastic model for a sand layer and an advection-diffusion model for suspended sediments. These two techniques for sand tracking enable the evaluation of diffusion and deposition more accurately in a series of sand processes from inside the hopper to the seafloor. The proposed model was validated with a dam-break simulation using fluid and saturated sand. In this validation, the time histories of the runout distance of the dam-break flow and the final deposition shape of the sand were compared, and they agreed well with previous experimental results. Thereafter, we conducted an experiment in which sand was dumped from a split hopper, and the model was validated using the results of this experiment. The performance of the model was examined, focusing on the spread of the suspended sediments, the velocity field of the fluid, and the deposition of sand. The flow characteristics induced by the dumped sand were revealed from the calculated results.

中文翻译：

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使用弹塑性固相模型的多相粒子法用于从分流料斗中倾倒的沙子的扩散

摘要 有必要准确预测漏斗驳船倾倒大量沙子的扩散和沉积范围，以实现沿海地区的高效围垦。许多先前的研究提出了有用的模型来模拟沙子在流体中的扩散行为；然而，他们的大多数模型都没有考虑沙子的沉积。本研究提出了一种基于粒子的数值模型，其中包括流砂相互作用。该模型使用两种方法来跟踪沙子：沙层的弹塑性模型和悬浮沉积物的平流扩散模型。这两种沙子追踪技术能够更准确地评估从料斗内部到海底的一系列沙子过程中的扩散和沉积。所提出的模型通过使用流体和饱和砂的溃坝模拟进行了验证。在本次验证中，比较了溃坝流的跳动距离和砂体最终沉积形状的时间历程，它们与先前的实验结果非常吻合。此后，我们进行了从分体式料斗倾倒沙子的实验，并使用该实验的结果验证了模型。检查模型的性能，重点是悬浮沉积物的扩散、流体的速度场和沙子的沉积。由计算结果揭示了由倾倒沙引起的流动特性。他们与之前的实验结果非常吻合。此后，我们进行了从分体式料斗倾倒沙子的实验，并使用该实验的结果验证了模型。检查模型的性能，重点是悬浮沉积物的扩散、流体的速度场和沙子的沉积。由计算结果揭示了由倾倒沙引起的流动特性。他们与之前的实验结果非常吻合。此后，我们进行了从分体式料斗倾倒沙子的实验，并使用该实验的结果验证了模型。检查模型的性能，重点是悬浮沉积物的扩散、流体的速度场和沙子的沉积。由计算结果揭示了由倾倒沙引起的流动特性。