Uncertainty analysis in submarine standard model resistance test

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.