1 / 18

Multi-layered approach to 2D urban flood modelling

Multi-layered approach to 2D urban flood modelling. A. S. Chen, B. Evans, S. Djordjević , D . A. Savić. Motivation. Improved efficiency of 2D flood modelling Reduced-complexity models Better numerical schemes Parallelisation (MPI, OPEN-MP, GPU) Adaptive meshes Grid coarsening.

eve
Download Presentation

Multi-layered approach to 2D urban flood modelling

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Multi-layered approach to 2D urban flood modelling A. S. Chen, B. Evans, S. Djordjević, D. A. Savić

  2. Motivation • Improved efficiency of 2D flood modelling • Reduced-complexity models • Better numerical schemes • Parallelisation (MPI, OPEN-MP, GPU) • Adaptive meshes • Grid coarsening

  3. Building Coverage Ratio (BCR)‏ • Area occupied by buildings within a grid cell Computing cell Building

  4. Conveyance Reduction Factors (CRFs) Widths blocked by buildings on cell boundaries (in both x and y directions) Computing cell Building

  5. Building alignment y a b c x d e f Computing cell Building

  6. Multi-layered approach

  7. Multi-layered approach

  8. Multi-layered approach

  9. Multi-layered approach

  10. BCR & CRF values (calculated by GIS tool)

  11. Grid coarsening approaches Plain view Longitudinal elevation profile

  12. Grid coarsening approaches • 1m grid resolution as the benchmark • 20m grid coarsening approaches • Averaged DEM (average of ground and roof elevation) • Single layer with BCR & CRFs • Multi-layered with BCR & CRFs • Error = difference from the benchmark

  13. Error map Single layer AveragedDEM Multi-layered

  14. Depth profile along the central longitudinal line

  15. Accuracy Efficiency

  16. Case study

  17. Multi-layered approach – Conclusions • Keeps fine detail in coarse grid (as in fine grid) • Grid-related error propagation reduced • More realistic surface flow paths in coarse grid • Enables much improved efficiency with little loss in accuracy • Applicable to any 2D grid-based model

  18. a.s.chen@ex.ac.uk

More Related