Feasibility Calculation of FaSTMECH for 2D Velocity Distribution Simulation in Meandering Channel

Abstract

Numerical flow simulation models in the riverine environments have been widely utilized for analyzing flow dynamics in various degrees in researches and practical applications. However, most of the simulated results have been validated based on the data from indoor experimental models or very limited in-situ measurements. Therefore, it has been required to more accurately validate the performance of the numerical models in terms of the detailed field observations. In particular, it was also hard to validate the performances of the existing numerical models in the real meandered river channels that encompass more sophisticated flow and geometric structures. Recently, advancements of the modern flow measuring instrumentations such as acoustic Doppler current profilers (ADCPs) enabled us to efficiently acquire the detailed flow field in the broad range of river channels, thus that it became to be possible to accurately validate any numerical models with the field observations. In this study, based on the detailed flow measurements in a actual meandered river channel using ADCP, we validated FaSTMECH model in iRIC in terms of water surface elevation, which is relatively new but began to get highlighted in the research areas. As the validation site, a meandering channel in River Experiment Center of KICT was chosen, which has 6.5 m of width, 0.38m of flow depth, 1.54 m3/s of flow discharge, 0.61 m/s of mean flow velocity, and 1.2 of sinuosity. As results, whereas the FaSTMECH precisely simulated water surface elevation, simulated velocity field in the bend did not match well with ADCP dataset.

Formulations and Diffusivity Coefficients of the 2D Depth‐Averaged Advection‐Diffusion Models: A Literature Review

“…The values obtained for the longitudinal coefficient D L /hu * (Table 3 and Figure 1b) fall in a range consistent with previous literature data, that is, typically D L /hu * ∼ (5-15) (Elder, 1959;Fischer, 1973). For the transverse coefficient, D T /hu * , calibrated values in the range (1.01-2.83) are found by Seo and Park (2009) and reused by Park et al (2020), which appears gener- From literature (section d in…”

“…Piasecki and Katopodes (1999) use a nonlinear optimization algorithm-based adjoint sensitivity method, while Morales-Hernandez et al ( 2019) systematically scan a range of plausible values. The observations used for this calibration are taken from scalar mixing experiments performed either in laboratory setups by Chang (1971), Baek et al (2006), Seo and Park (2009) or Morales-Hernandez et al (2019), or in field conditions by Hinz et al (1989) or Lee and Seo (2007).…”

Comparative Analysis of Inundation Mapping Approaches for the 2016 Flood in the Brazos River, Texas

“…Kenney and Freeman (2011) suggested that iRIC-FaSTMECH give a fair spatial understanding of water surface elevation, velocities, and sheer stress associated with high flows. Son et al (2014) showed that iRIC-FaSTMECH well simulated water surface levels in South Korea. Due to its simulation efficiency and utility in predicting water surface elevation during the flood event, iRIC-FaSTMECH is selected as the dynamic-based model in this study.…”

“…Son et al. () showed that iRIC‐FaSTMECH well simulated water surface levels in South Korea. Due to its simulation efficiency and utility in predicting water surface elevation during the flood event, iRIC‐FaSTMECH is selected as the dynamic‐based model in this study.…”

“…Not only can the iRIC-FaSTMECH provide the maximum inundation area at peak stage but it can also be used for simulating water level, flow velocity distribution for the floodplain, etc. (Ku and Kim 2014;Son et al 2014;Kail et al 2015). Kenney and Freeman (2011) suggested that iRIC-FaSTMECH give a fair spatial understanding of water surface elevation, velocities, and sheer stress associated with high flows.…”