Water diffusion coefficients

Ebook "Modelling water flow in unsaturated porous media: Accounting for nonlinear permeability and material heterogeneity" focuses on two issues related to mathematical and numerical modelling of flow in unsaturated porous media. In the first part numerical solution of the governing equations is discussed, with particular emphasis on the spatial discretization of highly nonlinear permeability coefficient. The second part deals with large scale flow in heterogeneous porous media of binary structure.

254p loivantrinh 29-10-2023 6 3   Download

This paper provides the calculation of the distribution of the concentrations of complex particles of the Sn(II) - citrate - water system in the solution volume, on the surface of the electrode, and in the diffusion layer for the tin citrate electrolyte containing an excess of the ligand. Based on the calculations for the electrodeposition of tin, an electrolyte containing [SnCit]2− complex at pH 8.0 was chosen.

11p tudichquannguyet 29-11-2021 11 1   Download

This paper presents the research results of theoretical model and numerical model of the washed-out process of alkylphenols in the late stage of water injection. The research results have proposed approximate analytical expression for concentration of alkylphenols at the late stage of water flooding. In this regard, at the sufficient large injection volume the alkylphenol concentration attenuates exponentially and the attenuation rate depends on parameters such as partitioning coefficient, oil saturation and interstitial velocity of water and oil and diffusion coefficients.

6p trinhthamhodang1220 21-07-2021 8 1   Download

In this work, the auto-correlation function of center of mass velocity has been used to deduce the mass diffusion coefficient (D) of water diluted in nitrogen using the Classical Molecular Dynamics Simulations (CMDS). The calculations have been performed at room temperature (296 K) for different mixtures of H2O in N2 and for 2.107 molecules from a five-sites potential.

7p koxih_kothogmih5 04-09-2020 22 2   Download

Determine the coefficient of water permeability, waterproofing marks, chloride ion diffusion coefficients of some types of concrete commonly used in bridge construction subjected to pre-compressive and direct-compression loads. Develop a predictive model for life expectancy using reinforced concrete bridges taking into consideration the effect of the load according to the criteria of initial corrosion of reinforcement in concrete. Application of life expectancy for the structure of reinforced concrete bridges.

27p kequaidan7 01-09-2020 28 2   Download

Nitrophenols (such as o-nitrophenol (ONP), p-nitrophenol (PNP), and 2,4-dinitrophenol (DNP)) are priority environmental pollutants. Their toxicity is pH dependent, and these molecular species of nitrophenols exhibit higher toxicity than their anionic counterparts. Herein, for the first time, a method for the in situ measurement of nitrophenols in acidic industrial wastewater was developed using diffusive gradients in thin films (DGT) with lignocellulose hazelnut shell-derived activated carbons (HSACs) as the binding agents. Nylon membranes (0.1 lm rated) with diffusion coefficients of (2.

10p trinhthamhodang1 14-11-2019 16 0   Download

This paper discussed the flexural and the compressive strengths of polyacrylic ester (PAE) emulsion and silica fume (SF)-modified mortar. The chloride ion permeability in cement mortar and the interfacial microhardness between aggregates and matrix were measured. The chemical reactions between polymer and cement-hydrated product were investigated by the infrared spectral technology. The results show that the decrease of porosity and increase of density of cement mortars can be achieved by the pozzolanic effect of SF, the water-reducing and -filling effect of polymer.

5p christian2605 11-10-2019 14 0   Download

Deterioration mechanism due to drying and shrinkage of patch-repaired regions in reinforced concrete structures is analytically investigated. The moisture diffusion coefficient of the repair materials was determined by varying the drying temperature and the polymer-tocement ratios of the polymer-modified cement mortar (PCM) in the experiment. It is found that the diffusivity of PCM increases in proportion to the polymer-to-cement ratio up to 10%.

14p christian2605 11-10-2019 13 0   Download

The kinetics of water absorption by chickpeas (Koçbafli, Kuflbafl›), lentils (green Pul) and beans (Battal, Dermason, Horoz, fieker) grown in Turkey were studied by a gravimetric method during soaking at 15, 25 and 40ºC to determine moisture diffusivity of these selected legumes.

8p aquaman27 15-01-2019 20 1   Download

In this investigation, the effect of steaming on the water vapor diffusion coefficient of poplar wood (Populus nigra L.) was studied. The diffusion coefficients were then measured based on Fick’s law of diffusion in steadystate conditions using the cup method.

5p vimb123 11-01-2019 16 1   Download

This paper proposes a 2D-quasi model for simulations of the lateral distribution of flow velocity and of unit water discharge in open-channel sections. The latters are obtained by solving the governing equation, which is derived from the Reynolds equations and allows for taking into account the gravity, bed shear stress, and turbulent diffusion force in calculations. Using the experimental data, a sensitivity analysis of modeling parameters, e.g. Manning coefficient and eddy viscosity was performed firstly.

8p thihuynh3006 16-03-2018 45 0   Download

CO2 injection has recently been shown to provide significant enhanced oil recovery from naturally fractured reservoirs 1 . Li et al. (2000) performed CO2 injection at 1750 psig on artificially-fractured cores after water flooding in a dead-oil system. Gravity drainage was suggested to be the dominant recovery mechanism in these tests, with significant tertiary oil recovery after water flooding. The authors observed that the recovery of initial oil at the start of the CO2 injection declined as the rock permeability decreased and the initial water saturation increased. Darvish et al.

274p namde01 11-04-2013 86 10   Download