Submitted to: Book Chapter
Publication Type: Book / chapter
Publication Acceptance Date: 10/10/2003
Publication Date: 12/5/2003
Citation: Jia, Y., Wang, S.S., Kuhnle, R.A., Alonso, C.V. 2003. Flow around a submerged trapezoidal spur dike. Book Chapter. Interpretive Summary: Unstable channel boundaries are often associated with the streams of agricultural watersheds. The productive use of agricultural and other lands as well as the habitat for fish and other aquatic organisms may be negatively impacted by unstable channels. Improved techniques to stabilize channel boundaries effectively and efficiently are needed. Improved computer models that aid in the design of techniques to stabilize channels are needed. A cooperative study was conducted between researchers from the Agricultural Research Service, National Sedimentation Laboratory and the Center for Computational Hydroscience and Engineering, University of Mississippi. This study featured a test of the computer model (CCHE3D) against flow data collected in the vicinity of a model spur dike (a structure widely used to protect stream banks). The comparison between measured and calculated flow velocities was excellent in the majority of cases. Improvements to computer models, such as CCHE3D, yield improved tools for watershed managers tasked with improving the environment of agricultural watersheds.
Technical Abstract: Numerical models that simulate free surface turbulent flows have made great progress in recent years. Their reliability and accuracy, however, must be determined by comparisons with measured data. This study assesses the performance of the free surface flow model, CCHE3D by comparing simulated values to the 2592 three-dimensional velocities measured at the Agricultural Research Service, National Sedimentation Laboratory. An acoustic Doppler velocimeter was used on a closely spaced grid to characterize the flow around a submerged model spur dike. Comparison of the measured and simulated velocities reveals that the model predicts the overall flow quite well. The error norm for the overall velocity comparison was about 0.0825.