水洞试验中阻塞比对阻力测量影响的数值模拟

为了使表面形貌减阻效果的水洞试验结果可以模拟和预测自由边界的结果、使水洞试验中验证过的有效减阻措施可以成功运用到无限场的情况，该文采用当今最流行的数值模拟方法，基于FLUENT软件对有水洞壁的模型试验和自由边界的无限场模型进行模拟。结果表明，水洞试验的阻塞比不得超过25％，否则在水洞试验中验证的有效减阻措施将无法应用到自由边界的无限场。在水洞试验阻塞比的有效范围内，随着阻塞比的增大或来流速度的增大，表面摩擦系数随之增大。

Numerical simulation of the effect of blockage ratio on drag measurement in water tunel test

The simulation analysis of testing model with water tunnel wall and infinite field model with free boundary is presented, which is calculated by means of numerical simulation using the popular software FLUENT. The object of this research is to make sure if the water tunnel test result about the effect of drag reduction is available to simulate and forecast the performance of infinite field case. The result indicates that the blockage ratio of the water tunnel test should not be over 25%, otherwise, the drag- reduction- effective measure demonstrated in the water tunnel test will not apply to infinite field with free boundary. In the effective range of the blockage ratio, the skin friction coefficient increases along with the increase of the blockage ratio or of the inlet velocity.