Study on the Design of Wetland Based on Hydrodynamic Condition - A Case of Candle Lake Wetland at Qingxiu Mountain Scenic Spot in Nanning City

Candle Lake wetland at Qingxiu Mountain scenic spot is one of the most important parts of the 'China Water Town' program in Nanning city. In order to figure out the scientific rationality of the situation and design of wetland system, five pilot programs are set up based on flow velocity of three inlets, quantity and position of five outlets and the shape of center island to simulate the flow field and velocity of Candle Lake wetland by using two-dimensional numeral simulation. The results indicated that as follows: 1. The flow field and velocity of Candle Lake wetland can't be improved by increasing the velocity of inlets in the wetland system, so that the problem of large standing water can’t be solved. 2. The flow field and velocity of Candle Lake wetland are influenced by the position and quantity of outlets, especially the outlet 2, outlet 4 and outlet 5, which can improve the flow field and velocity effectively. 3. The flow field and velocity of Candle Lake wetland are also influenced by the shape of shoreline. Optimizing shoreline of Chengxiang Island can improve the flow field and velocity of Candle Lake wetland near the island very well. The flow field and slow velocity of Candle Lake wetland can be improved effectively by the optimizing shape of the Chengxiang Island and the position of outlet 4 and outlet 5, and the problems of large standing water and circulation can be solved very well.