Literature Review Notes 2002-2004

Literature Review Notes

This morning spent time reading through articles from between 1999 to 2002 and two really stuck out:

citation FRACCAROLLO, L., & CAPART, H. (2002). Riemann wave description of erosional dam-break flows. Journal of Fluid Mechanics, 461. doi: 10.1017/S0022112002008455.

??citation??Cao, Z., Pender, G., Wallis, S., & Carling, P. (2004). Computational Dam-Break Hydraulics over Erodible Sediment Bed. Journal of Hydraulic Engineering, 130(7), 689. doi: 10.1061/(ASCE)0733-9429(2004)130:7(689).

Fraccarollo and Capart is interesting as they performed a number of physical model runs using different densities of sediment. These runs show quite clearly the debris type flow occurring at the nose of the wave, followed by “clear water”.

Cao et al in particular had a number of very interesting observations regarding dam break flows over mobile beds relevant to both modelling the flows and the need to account for the impacts of the bed for emergency response purposes:

The mobile bed can be significantly scoured; the dimensions of the scour hole are of similar order of magnitude to those of the flow itself Figs. 2 and 12 a. Therefore the rate of bed deformation is not negligible compared to that of flow change, characterizing the need for coupled modeling of the strongly interacting flow-sediment-morphology system as asserted by Cao et al. (2002). Previous models need to be reformulated if refined results are to be sought (e.g., CADAM 1998, 1999a,b)

Dam-break flows over mobile beds can provoke very active sediment exchange between the water column and the bed, and also produce a sharp spatial gradient of concentration, which must be incorporated in the momentum equation. Otherwise significant errors result Fig. 11, in contrast to Brufau et al. 2000 for debris flows. Previous models for dam-break prob- lems can be improved by using the complete, instead of sim- plified, momentum equations e.g., CADAM 1998, 1999a,b.

'It is also found that the free surface profiles and hydrographs are greatly modified by bed mobility, which has considerable implications for flood prediction.'

Also read through:

??citation??Chauhan, S. S., Bowles, D. S., & Anderson, L. R. (2004). Do current breach parameter estimation techniques provide reasonable estimates for use in breach modeling? 2004 Annual conf assoc of state dam safety officials, Phoenix, AZ, USA. Citeseer. Retrieved May 7, 2011, from http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.78.935&rep=rep1&type=pdf.

Which states the need for improved physical models for breach flow estimation and comments on some of the common production-type models (BREACH, MIKE11) in used for predicting breach hydrographs for embankment type dams.