Abstract： ASME PTC 19.1:2018 pdf download.Test Uncertainty. Refer to Nonmandatory Appendix B for values of the Student’s e statistic at other confidence levels and degrees of freedom. For situations in which the frequency distribution and degrees o...

ASME PTC 19.1:2018 pdf download.Test Uncertainty.

Refer to Nonmandatory Appendix B for values of the Student’s e statistic at other confidence levels and degrees of freedom. For

situations in which the frequency distribution and degrees of freedom are unspecified, a uniform distribution and large degrees of freedom are often assumed. For situations involving other frequency distributions, refer to an appropriate statistics textbook.

If the published information is presented as an ISO expanded uncertainty at a defined coverage factor. then the elemental

systematic standard uncertainty is estimated as the expanded uncertainty divided by the coverage factor.

I the published information is presented as a multiple of a standard deviation (e.g., 2-sigma’ or3-sigma), then the elemental

systematic standard uncertainty is estimated as the multiple of the standard deviation divided by the multiplier.

3-3.2.2.2 SpeciaL Test Data. Sometimes a separate, special test is needed to estimate the systematic error caused by a given

source. An example is a nonuniform flow effect on the determination of the average velocity at a given location in a test article. In this case, the determination of the average velocity from a distribution of measurements at that location can be used to

estimate the error when a smaller (probably more realistic) number of measurements is used to determine the average velocity at

that location. Another example is the determination of an average temperature of a surface with a limited number of probes. If the surface temperature is almost uniform at the test location. then the average from the separate measurements will approximate the

true average, lithe temperature is not uniform due to heat conduction effects, then a two- or three-dimensional heat conduction

analysis can be performed to estimate the error.

Recommended：