Inicio  /  Water  /  Vol: 15 Par: 5 (2023)  /  Artículo
ARTÍCULO
TITULO

Geometry of Local Scour Holes at Boulder-like Obstacles during Unsteady Flow Conditions and Varying Submergence

Oliver Schlömer and Jürgen Herget    

Resumen

Local scour holes are erosional bed structures that are related to different scientific disciplines in Earth science and hydraulic engineering. Local scouring at naturally placed boulders is ubiquitous, but many competing factors make it difficult to isolate the effects of a given variable. This is especially true for local scouring at natural instream obstacles that are exposed to unsteady flow conditions in the course of flood hydrograph experiments. Experimental investigations in laboratory flumes offer the advantage that boundary conditions can be systematically varied. We present novel experimental data on the impact of the submergence ratio, hydrograph skewness, and flow intensity on local scouring at boulder-like obstacles during unsteady flow and evaluate the effect of discharge chronologies. In total, 48 flume experiments on subcritical clear-water conditions and channel degradation were performed. The experimental results reveal that local scouring dominantly occurred at the rising limb when flow depth was comparable to the obstacle size, so the obstacle was unsubmerged. The steeper the rising limb, the quicker the local scour hole matured. The experimental results are relevant for the hydraulic interpretation of local scour holes found at boulders in the field. They may be utilized as a proxy for the minimum duration of the beginning stage of a flood.

 Artículos similares

       
 
Shiyu Lu, Huamin Yang and Cheng Han    
Due to the often substantial size of the real-world point cloud data, efficient transmission and storage have become critical concerns. Point cloud compression plays a decisive role in addressing these challenges. Recognizing the importance of capturing ... ver más
Revista: Algorithms

 
Lukas Sandmaier, Peter Meusburger and Helmut Benigni    
The complex flow conditions in Pelton turbines make it challenging to gain detailed insight into the local flow processes. However, CFD methods offer vast potential for developing and optimising Pelton turbines due to these flow conditions. In a comprehe... ver más

 
Julian Kimmerl and Moustafa Abdel-Maksoud    
Underwater radiated noise is part of the anthropogenic emissions into the environment and as such a pressing problem for the preservation of the marine ecosystem. In order to direct attention to the most relevant noise sources associated with ships it is... ver más

 
Xiang Zhang, Yuchuan Zhou and Lianying Li    
Recognizing vessel navigation patterns plays a vital role in understanding maritime traffic behaviors, managing and planning vessel activities, spotting outliers, and predicting traffic. However, the growth in trajectory data and the complexity of mariti... ver más

 
Angelo Rubino, Stefano Pierini, Sara Rubinetti, Michele Gnesotto and Davide Zanchettin    
The Mediterranean Sea is of great and manifold relevance for global oceanic circulation and climate: Mediterranean waters profoundly affect the salinity of the North Atlantic Ocean and hence the global ocean circulation. Ocean motions are forced fundamen... ver más