摘要:
为了改善拖曳水池的试验精度,对一条4.5m 潜艇标模 SUBOFF 进行重复拖曳阻力试验。本文参照 IT-TC 推荐规程中试验流体动力学不确定度分析规范,对由偏差极限引起的不确定度将由潜艇标模的几个外形、速度、阻力、以及温度、密度和粘性这几个测量系统分别进行估算;通过6次重复潜艇标模阻力试验结果的标准差分析,得到了摩擦阻力系数、总阻力系数的精密度极限;最后对该模型的摩擦阻力系数、总阻力系数进行了不确定度分析。结果表明:由温度引起的运动粘性系数的偏差极限占到摩擦阻力系数偏差极限的97%;总阻力系数的偏差极限98%来自于湿表面积的偏差极限;随着试验速度的提高,总阻力系数和剩余阻力系数的总不确定度降低。
Abstract:
To improve the test accuracy in the towing tank,repeated resistance tests of the submarine standard model were conducted.According to ITTC recommended procedures and guidelines for uncertainty analysis in experimental liquid dynamics,the test results were ana-lyzed.Uncertainty is caused by the bias limits related to the submarine standard model geomet-rical form,velocity,resistance,temperature,density and kinematical viscosity,and accordingly the bias limits were calculated.The standard deviation was got by six repeated resistance tests, and then the precision limits were calculated.The total uncertainty was estimated.The results show that,the bias limits of the kinematical viscosity coefficient caused by temperature uncer-tainty contributes to 97% of the bias limits of the friction resistance coefficient;98% of the bias limits of the total resistance coefficient comes from the bias limits of the wet surface area;as the test velocity increases,the total uncertainty of the total resistance coefficient and friction resist-ance coefficient reduces.
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