Analytical model for organic contaminant transport through GMB/CCL composite liner with finite thickness considering adsorption, diffusion and thermodiffusion

2021 ◽  
Vol 120 ◽  
pp. 448-458
Author(s):  
Ming-Qing Peng ◽  
Shi-Jin Feng ◽  
Hong-Xin Chen ◽  
Zhang-Long Chen ◽  
Hai-Jian Xie
Keyword(s):  
Contaminant Transport ◽  
Analytical Model ◽  
Finite Thickness ◽  
Organic Contaminant ◽  
Composite Liner

Analytical Model for Degradable Organic Contaminant Transport through a GMB/GCL/AL System

2018 ◽  
Vol 144 (3) ◽  
pp. 04018006 ◽  
Author(s):  
Haijian Xie ◽  
Chunhua Zhang ◽  
Shijin Feng ◽  
Qiao Wang ◽  
Huaxiang Yan
Keyword(s):  
Contaminant Transport ◽  
Analytical Model ◽  
Organic Contaminant

An Analytical Model for the Generation of Residual Stresses in Sprayed Coatings Deposited Progressively onto Planar Substrates

1997 ◽  
Author(s):  
Y.C. Tsui ◽  
T.W. Clyne
Keyword(s):  
Residual Stress ◽  
Analytical Model ◽  
Finite Thickness ◽  
Misfit Strain ◽  
Substrate Thickness ◽  
Layer By Layer ◽  
Spreadsheet Program ◽  
Spray Coatings ◽  
Stress Levels ◽  
Planar Substrates

Abstract An analytical model has been developed to predict the residual stress distributions in thermal spray coatings on substrates of finite thickness. This is based on the concept of a misfit strain, caused by either the quenching of splats or by differential thermal contraction during cooling. During spraying, the coatings are asssumed to deposit on the substrate in a progressive (layer-by-layer) manner. Although the misfit strain ("the quenching strain") is the same for each successive incremental layer of deposit, this is imposed each time on a "substrate" of changing thickness. The final stress distribution will in general differ from that which would result if the coating were imposed on the substrate (with the same misfit strain) in a single operation. The model is straightforward to apply: for example, it can be implemented using a standard spreadsheet program. The required input data are the quenching strain (or stress), the spraying temperature, material properties and specimen dimensions. Comparisons have been made between the predictions from this model and from a numerical model for two plasma sprayed systems. Good agreement is observed. The effects of varying certain parameters, such as coating thickness, substrate thickness, coating stiffness, etc, are readily explored, so that the model provides a useful tool for controlling residual stress levels. Application of the model to determine the quenching stress, in conjunction with the use of a curvature monitoring technique, is briefly outlined. In addition, an analysis is made of the errors introduced by using Stoney's equation to deduce stress levels from curvature measurements.

scholarly journals Detection of contaminant plumes released from landfills

2006 ◽  
Vol 3 (3) ◽  
pp. 819-857
Author(s):  
N. B. Yenigül ◽  
A.T. Hendsbergen ◽  
A. M. M. Elfeki ◽  
F. M. Dekking
Keyword(s):  
Simulation Model ◽  
Contaminant Transport ◽  
Analytical Model ◽  
Detection Probability ◽  
Average Concentration ◽  
Contaminant Plume ◽  
Contaminant Plumes ◽  
Heterogeneous Aquifer ◽  
Monitoring Well ◽  
Detection Probabilities

Abstract. Contaminant leaks released from landfills are a significant threat to groundwater quality. The groundwater detection monitoring systems installed in the vicinity of such facilities are vital. In this study the detection probability of a contaminant plume released from a landfill has been investigated by means of both a simulation and an analytical model for both homogeneous and heterogeneous aquifer conditions. The results of the two models are compared for homogeneous aquifer conditions to illustrate the errors that might be encountered with the simulation model. For heterogeneous aquifer conditions contaminant transport is modelled by an analytical model using effective (macro) dispersivities. The results of the analysis show that the simulation model gives the concentration values correctly over most of the plume length for homogeneous aquifer conditions, and that the detection probability of a contaminant plume at given monitoring well locations match quite well. For heterogeneous aquifer conditions the approximating analytical model based on effective (macro) dispersivities yields the average concentration distribution satisfactorily. However, it is insufficient in monitoring system design since the discrepancy between the detection probabilities of contaminant plumes at given monitoring well locations computed by the two models is significant, particularly with high dispersivity and heterogeneity.

Modeling Organic Contaminant Transport through Reactive Media

2018 ◽  
Vol 144 (9) ◽  
pp. 04018084 ◽  
Author(s):  
Ke Yin ◽  
Priscilla Z. Viana ◽  
Karl J. Rockne
Keyword(s):  
Contaminant Transport ◽  
Organic Contaminant ◽  
Reactive Media

Interpretation of the transient flow rate obtained from constant-head tests conducted in situ in clays

1993 ◽  
Vol 30 (4) ◽  
pp. 600-606 ◽  
Author(s):  
K.S. Novakowski
Keyword(s):  
Analytical Model ◽  
Flow Rate ◽  
Finite Thickness ◽  
Skin Permeability ◽  
Type Curves ◽  
Partial Penetration ◽  
Thickness Skin ◽  
Skin Zone ◽  
Constant Head

Hydraulic tests conducted in situ using a source condition of constant head are frequently employed to determine the hydraulic properties of low-permeability clays. In this paper, an analytical model is developed for analyzing the results of a constant-head test conducted under conditions where the influence of finite-thickness skin and partial penetration are present at the source well. The analytical model is derived by application of the Laplace transform method with respect to time and the finite Fourier cosine transform with respect to the vertical coordinate. The solution is used to produce type curves of dimensionless flow rate versus dimensionless time so as to investigate the influence of finite thickness skin and partial penetration on the results of constant-head tests. Results show that the presence of a skin zone of finite thickness having permeability less than the formation produces an inflection point in the type curves at which point the dimensionless flow rate tends asymptotically towards a steady value. For the case where the skin and formation permeabilities are similar, these type curves can be used to uniquely define both the skin and formation properties. Where the skin zone is very thin, the shape of the type curves mimics the curve for a uniform, fully confined medium, and thus only the properties of the skin are measured using type-curve analysis. Conversely, the type curves for the case where the skin zone is of greater permeability than the formation show a unique and interpretable shape for each skin thickness and ratio of formation to skin permeability over most practical values of hydraulic diffusivity. Additional effects due to partial penetration were found to be pronounced in piezometers completed with small screen lengths. Particular conditions where the conventional steady approximation can be used are also discussed. Key words : constant-head test, flow rate, skin zone, partial penetration.

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