3D Numerical Simulation of the Process of Draining into a Lock

2013 ◽  
Vol 838-841 ◽  
pp. 1667-1670
Author(s):  
Ming Hua Deng ◽  
Zhu Gao ◽  
Da Wei Mao
Keyword(s):  
Numerical Simulation ◽  
Integral Method ◽  
Full Time ◽  
Inertia Effect ◽  
3D Numerical Simulation ◽  
Precise Estimation ◽  
Practical Engineering ◽  
Order Of Magnitude ◽  
Cfd Method ◽  
Ship Lock

In some textbooks, the Steady-flow Integral Method (SIM) was used to compute the full time of Draining into a Ship Lock, although this method is simple, it only provides a coarse estimation and somehow misleads the students due to approximating the unsteady problem as a steady one and ignoring the inertia effect. The more complex CFD-based model, FLUENT, was used to compensate these shortcomings, the Volume of Fluid (VOF) method was utilized to calculate the free-surface, and the turbulence closure was obtained by the realizable k-ε turbulence model. The values of draining time derived from the two different methods have the same order of magnitude. By CFD, a more precise estimation of the draining time and abundant details about the draining process were obtained. In practical engineering, the geometry of a lock is far more complex than here, the SIM is hard to satisfy the demands for a optimal design, while the CFD method is a nice choice for this purpose.

Computation of Filling Time of a Ship Lock

2012 ◽  
Vol 256-259 ◽  
pp. 2509-2513
Author(s):  
Zhu Gao ◽  
Shi Long Fang ◽  
Xiao Tao Shi ◽  
Zheng Hua Gu
Keyword(s):  
Water Surface ◽  
Velocity Fields ◽  
Vof Method ◽  
Filling Process ◽  
Integration Approach ◽  
Precise Estimation ◽  
Filling Time ◽  
Practical Engineering ◽  
Order Of Magnitude ◽  
Ship Lock

In this paper, Steady-flow Integration Approach (SIA) and Volume of Fluid (VOF) method are both used to calculate the filling time of a ship lock. The values of filling time derived from these two different methods have the same order of magnitude. SIA is only used to give a quick but coarse estimation; however in the application of more time-consuming VOF approach, the fluctuations of water surface are additionally considered and computed, It provides a more precise estimation of the filling time and a more realizable details about the filling process. In practical engineering, the geometry of ship lock will be far more complex than here; the SIA is not enough to satisfy the demands for a desired design. The VOF method will be a nice choice and give reasonable predictions of filling time, water fluctuations and velocity fields in the ship lock.

Non-stationary process characteristics of the gas outflow into a liquid

2019 ◽  
Vol 14 (2) ◽  
pp. 82-88
Author(s):  
M.V. Alekseev ◽  
I.S. Vozhakov ◽  
S.I. Lezhnin
Keyword(s):  
Numerical Simulation ◽  
Liquid Column ◽  
Gas Content ◽  
Liquid Lead ◽  
Gas Flows ◽  
Asymptotic Model ◽  
Process Characteristics ◽  
Significant Difference ◽  
Order Of Magnitude ◽  
Volume Method

A numerical simulation of the process of the outflow of gas under pressure into a closed container partially filled with liquid was carried out. For comparative theoretical analysis, an asymptotic model was used with assumptions about the adiabaticity of the gas outflow process and the ideality of the liquid during the oscillatory one-dimensional motion of the liquid column. In this case, the motion of the liquid column and the evolution of pressure in the gas are determined by the equation of dynamics and the balance of enthalpy. Numerical simulation was performed in the OpenFOAM package using the fluid volume method (VOF method) and the standard k-e turbulence model. The evolution of the fields of volumetric gas content, velocity, and pressure during the flow of gas from the high-pressure chamber into a closed channel filled with liquid in the presence of a ”gas blanket“ at the upper end of the channel is obtained. It was shown that the dynamics of pulsations in the gas cavity that occurs when the gas flows into the closed region substantially depends on the physical properties of the liquid in the volume, especially the density. Numerical modeling showed that the injection of gas into water occurs in the form of a jet outflow of gas, and for the outflow into liquid lead, a gas slug is formed at the bottom of the channel. Satisfactory agreement was obtained between the numerical calculation and the calculation according to the asymptotic model for pressure pulsations in a gas projectile in liquid lead. For water, the results of calculations using the asymptotic model give a significant difference from the results of numerical calculations. In all cases, the velocity of the medium obtained by numerical simulation and when using the asymptotic model differ by an order of magnitude or more.

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