Numerical Simulation 2019/2020: Choosing the right model in applied hydraulics, 11 Jan 2020, Marlin Shlewet, Alaa Abusamra CALIBRATED ROUGHNESS VALUES FOR DIFFERENT FLOW SCENARIOS Marlin, Shlewet Mailing address
[email protected] Alaa, Abusamra Mailing address
[email protected] SUB TITLE CASE STUDY: RIVER RHINE SECTION RUHRORT- WESEL, 1D MODELLING KEY WORDS Manning coefficient, Validation, Calibrition, Water Level, Unsteady Simulation, Cross Section, Boundary Conditions, Flood Period, Dry Period. ABSTRACT Roughness coefficient is the main important parameter in numerical surface water models, where flow discharge, water level and velocity are calculated from surface water eequations depending on it. This parameter´s value is non-measurable directely from the observation water field, but related to different other factors. The relevant concerned question in this paper is how can we define the exact value which can approximate our simulated model to the real case with enough accuracy?. In this present case study, 1D hydrodynamic model using HEC-ras software has been setted-up -to section of River Rhine approximately 34.1 km length, consists of 69 cross- sections from Ruhrort in the South to Wesel in the North in Germany- using observation time series flow data and H/Q relationship of a flood return period 10 years. The model is used to calibrate the optimized roughness value using evaluation coefficients method , comparing with the observation water level values down stream the river, after running the unsteady flow simulation for three different flow discharge scenarios (high,mean and low flow discharge) and using different manning values between the range 25-40 for each.