Author(s): Wenming Zhang; David Z. Zhu; Faruk Bhuiyan

Linked Author(s): David Z. Zhu

Keywords: No Keywords

Abstract: A field study was conducted to evaluate the mixing characteristics downstream of a multiport diffuser in the Athabasca River, Canada. The study reach was from 0.5 km upstream to 32.6 km downstream of Al-Pac's diffuser. The field work involves a dye test, bathymetry survey and velocity measurement. In the near field, water samples were collected at four different depths, thus allowing us to evaluate the performance of the diffuser. Analysis shows that the dilution can reach32 times at 12.8 m where individual jets from different ports of the diffuser start merging. A mixing zone model, CORMIX, was used to predicate the effluent mixing from the diffuser. The result shows that CORMIX models very well from vertically fully mixing to 2.26 km downstream of the diffuser. Using the method of moment and streamtube, the reach-averaged dimensionless transverse mixing coefficient was calculated as/ () tεHU*= 0.31. Combined with other previous dye tests, the effect of river discharge on dimensionless transverse mixing coefficient was then examined. In this study, the mean value of/ () tεHU*is 0.35±0.05 for 5 discharges ranging from229 to 960 m3/s, which appears that river discharge does not affect/ () tεHU*.

DOI:

Year: 2009