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摘要
Turbulent flow in porous media, terrestrial and aquatic canopies, and urbanlike roughness is usually investigated using the macroscopic approach, which is based on the volume average theory (VAT). Two different methodologies have been developed in the past leading to different equations for both the mean and the turbulence quantities: time-averaging the volume-averaged equations and volume-averaging the time-averaged equations. In this study four models of the volume-averaging methodology are applied for modeling the flow in open channels with submerged vegetation. The vegetation is considered rigid, simulated as cylindrical roughness in a staggered or nonstaggered arrangement. Three of the models are of the k-epsilon type and one is of the Reynolds stress type. The latter has been applied using a modified e equation to account for the extra dissipation attributable to vegetation. Numerical results for both mean and turbulence flow characteristics are compared against available experimental measurements for dense canopies under shallow and deep flow conditions. In addition, relevant characteristics (displacement thickness, canopy shear layer parameter, mixing length, penetration length scale, and etc.) are calculated for both computed and experimental data for assessing the performance of the models. DOI: 10.1061/(ASCE)HY.1943-7900.0000307.
- 出版日期2011-3
