Urban Drainage Systems PhD Candidate: Mahmood Mahmoodian Daily - PowerPoint PPT Presentation

Surrogate Modelling for Urban Drainage Systems PhD Candidate: Mahmood Mahmoodian Daily supervisor: Ulrich Leopold

WHAT IS SURROGATE MODELLING? An analogy Detailed rabbit simulator (model) Real rabbit Surrogate model 1 Surrogate model 2 Surrogate model 3 2

MY CHALLENGE Urban Drainage System Modelling Storage Tank 1 Zoom in Storage Tank 2 WWTP Computationally expensive for: • Real-time control (RTC) • Calibration • Optimisation • 3 Uncertainty propagation

POSSIBLE SOLUTIONS: To obtain fast simulators Develop a surrogate of already existing simulators (e.g. InfoWorks,…) 1. Data-driven approaches 2. Projection-based approaches 3. Hierarchical or multi-fidelity approaches 4. Hybrid approaches 4

METHOD 2: A DATA-DRIVEN APPROACH GAUSSIAN PROCESS EMULATOR (GPE) Olson & Chang (2013) Y: model output of interest µ β : a mean function which is considered linear in time ξy : a vector of covariance matrix parameters. Training data: Validation Validation Main advantages: Main disadvantages: • • Non-intrusive and generic method Limited number of parameters • • Uncertainty quantification Short simulations 5

METHOD 2: A HYBRID METHOD (MODEL-DRIVEN + DATA-DRIVEN) mass balance Storage Tank Volume Change: Validation Model-driven Data-driven Main advantages: Main disadvantages: • • Super fast! (1400 times faster) Partly-intrusive and case-specific • • Useful for longer simulations Uncertainty quantification? 6

TAKE AWAY MESSAGE There is NO generic remedy of surrogate modelling for all applications Selection criteria: 1. Reduce the runtime significantly 2. Give a quantification of the uncertainty 3. Be easily applicable in practice Example: real-time control (RTC) Data-driven GPE approach! 7

THANK YOU FOR YOUR ATTENTION! Keep It as Simple as Possible! (Law of parsimony, Ockham's Razor) Email: mahmood.mahmoodian@list.lu 8

PARTNERS AND ACKNOWLEDGEMENTS This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 607000. 9 www.quics.eu