Quantification of Aleatory Uncertainty in Blast Wave Problem

As uncertainty always exists in the modeling and simulation of complex engineering problems, the identification and analysis of its source and the quantification of its degrees play an important role in assessing the credibility of the modeling and simulation results.In this paper, the concept of uncertainty as well as uncertainty quantification process was presented in the modeling and simulation, with the blast wave problem used as a typical example to illustrate the detailed process for the quantification of the aleatory uncertainty.The expectations and variances of density, pressure, velocity and internal energy were calculated and, moreover, the probability density function of the shock wave position was obtained using the Monte-Carlo and the non-intrusive polynomial chaos (NIPC).The results were consistent with each other, which verified that the NIPC method is an efficient approach in the uncertainty quantification of a complex nonlinear system.