A new model for predicting relative nonwetting phase permeability from soil water retention curves

Kuang, Xingxing; Jiao, Jiu Jimmy

doi:10.1029/2011wr010728

Cited by 28 publications

(45 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22,29 It can be seen that there is good agreement between the model predictions and the experimental data. 22,29 The validity of the present fractal model for the capillary pressure of water phase in unsaturated porous rocks is thus verified. Figure 2 also shows that the capillary pressure for water phase increases with the decrease of saturation in unsaturated porous rocks.…”

Section: Fractal Methods and Calculationssupporting

confidence: 51%

See 1 more Smart Citation

A Fractal Model for Water Flow Through Unsaturated Porous Rocks

et al. 2018

View full text Add to dashboard Cite

In this work, considering the effect of porosity, pore size, saturation of water and tortuosity fractal dimension, an analytical model for the capillary pressure and water relative permeability is derived in unsaturated porous rocks. Besides, the formulas of calculating the capillary pressure and water relative permeability are given by taking into account the fractal distribution of pore size and tortuosity of capillaries. It can be seen that the capillary pressure for water phase decreases with the increase of saturation in unsaturated porous rocks. It is found that the capillary pressure for water phase decreases as the tortuosity fractal dimension decreases. It is further seen that the capillary pressure for water phase increases with the decrease of porosity, and at low porosity, the capillary pressure increases sharply with the decrease of porosity. Besides, it can be observed that the water relative permeability increases with the increase of saturation in unsaturated porous rocks. This predicted the capillary pressure and water relative permeability of unsaturated porous rocks based on the proposed models which are in good agreement with the experimental data and model predictions reported in the literature. § Corresponding author. This is an Open Access article published by World Scientific Publishing Company. It is distributed under the terms of the Creative Commons Attribution 4.0 (CC-BY) License. Further distribution of this work is permitted, provided the original work is properly cited. 1840015-1 B. Xiao et al.The proposed model improved the understanding of the physical mechanisms of water flow through unsaturated porous rocks.

show abstract

Section: Fractal Methods and Calculationssupporting

confidence: 51%

“…However, the water relative permeability (k rw ) cannot be obtained by the proposed model. 22 Recently, Zhao et al 23 investigated the pore structure of Lucaogou tight oil formation by NMR measurements. And the heterogeneity of pore structure was studied by multifractal analysis.…”

Section: Introductionmentioning

confidence: 99%

A Fractal Model for Water Flow Through Unsaturated Porous Rocks

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The experimental datasets for Poudre river sand were taken from Brooks & Corey (). The fitted parameters for the van Genuchten model, Equation , were taken from Kuang & Jiao (). Overall, the proposed Equation was slightly closer to the measured soil water retention data when air began to enter.…”

Section: Resultsmentioning

confidence: 99%

A new equation for the soil water retention curve

Kuang

Jiao

2014

European J Soil Science

View full text Add to dashboard Cite

Summary The soil water retention curve is a fundamental characteristic of unsaturated zone flow and transport properties. Recent studies show that an air‐entry value is needed in a soil water retention equation in order to provide a better prediction of relative hydraulic conductivity. A new equation considering the air‐entry value is proposed to describe the soil water retention curve. The performance of the proposed equation is contrasted with a well‐supported equation by comparing measured and calculated data for 14 soils, representing various soil textures, which range from sandstone to clay. Results show that the proposed equation provides adequate characterization of the soil water retention curves. The equation for predicting relative hydraulic conductivity is derived from the proposed soil water retention equation. An empirical equation for relative hydraulic conductivity is also used. Our results show that the agreement between the predicted and measured relative hydraulic conductivities is improved by the combinations of the proposed equation and the relative hydraulic conductivity equations. The proposed equation is mathematically simple and it can easily be implemented in unsaturated flow and multiphase flow numerical models.

show abstract

“…Thus, moist conditions in the bottom cover soil significantly impeded vertical gas diffusion. Gas permeability is less affected by moisture, and using the Kuang and Jiao (2011) model and parameters in Table 3, the gas permeability in the bottom cover soil was estimated to be 78% of that in the top cover. While moisture did not significantly reduce gas permeability, it may have reduced cracking and helped maintain the low gas permeability expected for this 47% silt/34% clay (Atwill et al, 2002) cover soil.…”

Section: Moisture Conditions Of Cover Soilmentioning

confidence: 99%