基于CFD的大型沉井拖航水阻力数值模拟与预测

Numerical simulation and prediction on towing resistance of large caissons based on CFD

针对大型沉井拖航过程中的水阻力计算问题,利用CFD进行不同拖航速度和不同迎流角组合工况下沉井拖航水阻力数值模拟.对数值模拟结果进行分析,提出以水流速度为1.0 m/s时的CFD阻力计算结果作为预测基准值的预测方法.结果表明,该预测方法具有较高的精度,预测结果与CFD计算结果的误差在-2.0%-1.0%之间.使用预测方法计算沉井拖航水阻力时,对每个迎流角只需计算一个工况下的结果,可以大幅度减少计算量.

To solve the towing resistance problem of large caissons, the numerical simulation is carried out on towing resistance of caissons under composite conditions of different towing speeds and impacted angles. By analyzing the numerical simulation results, a prediction method is proposed, where the resistance obtained by CFD when the flow velocity is 1.0 m/s is set as the reference value when predicting towing resistance of caissons. The results show that, the prediction method is of high accuracy, and the error between the results predicted and calculated by CFD is from -2.0% to 1.0%. When using the prediction method for the towing resistance of caissons, the result under only one condition is calculated for each impacted angle, which can greatly reduce the amount of calculation.