In this work, sluice gate flows are investigated in detail using CFD simulations and an approach based on the integral momentum balance is elaborated for the calculation of the discharge under standard and inclined sluice gates. For this purpose, different control volumes are first analyzed and rated. To solve the momentum balance of the most suitable control volume, the pressure forces at the control volume boundaries in the upstream region, at the sluice gate wall and at the sluice gate opening as well as the momentum coefficients at the control volume boundaries in the headwater and at the sluice gate opening are required. To determine these, CFD simulations are first performed and analyzed for common relative gate opening heights ε and angles of inclination α. To determine the pressure forces, the pressure distributions from the CFD simulations are parameterized as a function of relative sluice gate opening and angle of inclination. By integrating the parameterized pressure distributions, it is then possible to determine the pressure forces relevant for the integral momentum balance as a function of the relative sluice gate opening and the angle of inclination. The momentum coefficients are also first determined from the CFD simulations and then parameterized as a function of the relative sluice gate opening and angle of inclination. With the parameterization formulas for pressure forces and momentum coefficients determined in this way, the discharge of standard and inclined sluice gates can be calculated with the aid of the integral momentum balance. The plausibility of the approach was confirmed by comparison with measured values and calculations available in the relevant literature. The pressure distributions and momentum coefficients, initially assumed to be constant across the width, are further investigated for the 3D case for different relative sluice gate widths. Deviations in the pressure distributions and velocity profiles were found due to three-dimensional flow structures, which in previous work were shown to be constant across the width. Likewise, for very narrow sluice gates, the ever-increasing influence of the frictional forces of the sidewalls was found. To take these 3D effects into account in the momentum balance, a 3D coefficient is introduced. With this coefficient, accurate calculations can be made for narrow sluice gates where 3D effects are relevant.    «

In this work, sluice gate flows are investigated in detail using CFD simulations and an approach based on the integral momentum balance is elaborated for the calculation of the discharge under standard and inclined sluice gates. For this purpose, different control volumes are first analyzed and rated. To solve the momentum balance of the most suitable control volume, the pressure forces at the control volume boundaries in the upstream region, at the sluice gate wall and at the sluice gate openin...    »