Uncertainty Modelling in Engineering

Solid Mechanics Seminar, 13:00-16:00, Friday, 27 June 2014

Uncertainty modelling in Engineering

13:00-13:30 Jan Havelka: Efficient methods for propagation of uncertainty in description of groundwater flow

Diploma thesis supervised by Jan Sýkora

Numerical simulations have become popular approach for solving engineering problems. The progress of computer technology then enables to solve more complex models and consequently to get more information about system behavior. Such a complex problem is here represented by the extension of deterministic material model by uncertain inputs, which may take origin in the lack or inaccuracy of the measurements. Therefore the aim of this work is to create an algorithms and to compare currently used methods for solving partial differential equations with uncertain input parameters in the description of groundwater flow.

13:30-14:00 Anna Kučerová: Stochastic Modelling of Heterogeneous Materials based on Image Analysis

Macroscopically heterogeneous materials, characterized mostly by comparable heterogeneity lengthscale and structural sizes, can no longer be modelled by deterministic approach. It is convenient to introduce stochastic approach with uncertain material parameters quantified as random fields. Nevertheless, introduction of random fields brings higher demands on quality of input data, especially on inputs of covariance functions representing the spatial randomness. The present contribution is devoted to the construction of random fields based on image analysis utilizing statistical descriptors, which were developed to describe the different morphology of two-phase random material. The whole concept is demonstrated on a simple numerical example of stationary heat conduction where interesting phenomena can be clearly understood.