The uncertainty and truth-value assessment in the verification and validation of CFD

The idea and definitions for verification and validation of CFD or EFD are reviewed. The uncertainty is defined as the maximum error between counting datum of CFD or testing datum of EFD and its correspondent truth value. Since the truth value calculated or tested is unknown, there is no explicit expression for the uncertainty. In this paper, a new expression of uncertainty is given. We consider that the counting or testing value can be approximated to the first n digil number of truth values. Based on this consideration, the uncertainty of CFD or EFD and the approximate truth value can be assessed. If there are a great of counting or testing sample data, according to statistical theory and uniform design method, we can give the calculation method to get the values which accurate to first n bits of the truth values and the uncertainty. Then the verification and validation of CFD or EFD can be performed agreeably.