SWAN模型模拟风浪场侧边界失真范围研究

Researches of distortion region near lateral boundaries for SWAN model calculating wind wave fields

鉴于SWAN模型存在着不能有效地模拟固壁边界附近风浪场的缺点,即在边界附近所模拟的波要素存在失真的现象,研究了在不同水深、风速和风向情况下模型侧边界附近波要素的失真范围,并对计算结果进行了详细的分析。结果表明水深、风速和风向对于侧边界附近波要素的失真范围具有不同的影响,即在风速一定的情况下,失真范围随着水深的增大而增大;水深一定的情况下,失真范围随着风速的增大而减小、随着风向的增大而增大。在利用SWAN模型模拟计算近岸或内陆湖泊风浪场时,必须采取适当的措施以减少实际计算域侧边界附近计算结果的失真范围。

Because the wind wave model Simulating WAves Nearshore （ SWAN） cannot effectively simulate the wave fields near the lateral boundaries, the distortion regions of calculated wave factors including wave heights, periods and directions near the lateral boundaries are carefully studied in the case of different water depths, wind speeds and wind directions respectively. The calculation results show that the effects of water depth, wind speed and wind direction on the distortion regions are different. In the case of a certain wind speed, the greater the water depth is, the larger the distortion region is;in the case of a certain water depth, the greater the wind speed is, the smaller the distortion region is, and the greater the wind direction is, the larger the distortion region is. Therefore, when SWAN is employed to calculate the wind wave fields near the shorelines of sea or of inland lakes, the appropriate methods must be adopted to reduce the calculation errors.