Efficient computation of unsteady flow in complex river systems with uncertain inputs

Abstract

This paper examines the modelling and computational issues of a framework for representing uncertain inflows in river systems using the polynomial chaos approach. Ensemble forecasts are used to construct a Karhunen–Loève expansion of random inflows. The statistics of the stochastic outflow of the system are computed using stochastic collocation. The dynamics of the river system are efficiently simulated using the performance graphs approach.

Keywords:

• Karhunen–Loève expansion
• polynomial chaos
• stochastic collocation
• reservoir modelling

2010 AMS Subject Classifications::

• 65C20
• 35Q35
• 93E20

Acknowledgements

This research was supported in part by the Bonneville Power Administration through the Technology Innovation Program, grant number TIP-258. The authors would like to thank an anonymous referee for many constructive suggestions.