落差工周边的水流模拟计算

为了维护和健全河流丰富的生态系，在河流中设置稳定河床作用的落差工时应注意尽可能的易于鱼类上下游动．目前，一种通过铺设坡道实现鱼道全面化的落差工正在日本受到关注，本论文为设计这种落差工。建立了一个应用MacCormack计算方法来预测其周边水流状况的模拟计算模型，并对两种形状的落差工进行水流模拟．计算结果表明：在落差工及其铺设的坡道的中央设有缺口的情况下，周边水流呈现显著的水流多样性，此外，其缺口确保了河流在平水时也能提供局部的所需水深，是一种比较适于鱼类上下游动的落差工。

Flow Simulation Surrounding Falling Works

In order to protect should be fully considered when a and repair the abundant fiver ecosystem, convenience for fish movements falling work is constructed in the fiver to stabilize riverbed. A new kind of falling work with a full-scale fishway by paving a slope in the falling work catches attention in Japan. This paper develops a numerical model using MacCormack method to predict the flow condition surrounding the works. The model is employed to simulate two cases of falling works, and the calculation results show that the flow condition has significant diversity when an opening is given in the falling work. The opening may also ensure the necessary water depth in part for fish movement even in low water season, and thus the falling works proves to be a suitable kind for fish movement up and down the river.