scholarly journals A Novel Analytical Model of Solute Transport in an Aquifer-Aquitard System with Mixing Processes in the Reservoirs

2022 ◽  
Author(s):  
Wenguang Shi ◽  
Wang Quanrong
Keyword(s):  
Experimental Data ◽  
Solute Transport ◽  
Analytical Model ◽  
Poor Performance ◽  
Controlled Experiment ◽  
Analytical Models ◽  
Observation Data ◽  
The Novel ◽  
Mixing Processes ◽  
Concentration Variation

Abstract Analytical models have been widely used to aid understanding the physical and chemical processes of tracer (or chemicals) in an aquifer-aquitard system in the laboratory-controlled experiment, when the observation data is few or not available during the experiment. When injecting tracer into (or extracting them from) the aquifer-aquitard system during experiments, the pre-inlet and after-outlet reservoirs are indispensable. However, the concentration variation in the reservoirs was not treated properly in previous analytical models, resulting in poor performance in interpreting experimental data. In this study, new mathematical models describing the concentration variation in the pre-inlet and the after-outlet reservoirs are proposed, and they are integrated into the novel analytical model. The novel analytical model is developed under the mobile-immobile (MIM) framework in the aquifer-aquitard system, considering the longitudinal and vertical dispersion, the advection, and the first-order chemical reaction in both aquifer and aquitard. A finite-difference solution is developed and the experimental data are employed to test the new analytical model. Results indicate that the concentration variation in the reservoirs is important to solute transport in the aquifer-aquitard system in the laboratory-controlled experiment, and the new analytical model outperforms the previous models in interpreting experimental data. The global sensitivity analysis demonstrates that the output concentration of solute transport in the aquifer-aquitard system is most sensitive to the volume of water in the pre-inlet reservoir. The contribution of the diffusion effect to the total mass flux of tracer crossing the aquifer-aquitard interface is much smaller than the contribution of the dispersive and advective effects.

scholarly journals Approximate Analytical Models of Shock-Wave Structure at Steady Mach Reflection

Fluids ◽  
2021 ◽  
Vol 6 (9) ◽  
pp. 305
Author(s):  
Mikhail V. Chernyshov ◽  
Karina E. Savelova ◽  
Anna S. Kapralova
Keyword(s):  
Experimental Data ◽  
Shock Wave ◽  
Comparative Analysis ◽  
Analytical Model ◽  
Mach Reflection ◽  
Supersonic Jet ◽  
Wave Structure ◽  
Analytical Models ◽  
Analytical Prediction ◽  
Shock Wave Structure

In this study, we obtain the comparative analysis of methods of quick approximate analytical prediction of Mach shock height in planar steady supersonic flows (for example, in supersonic jet flow and in narrowing channel between two wedges), that are developed since the 1980s and being actively modernized now. A new analytical model based on flow averaging downstream curved Mach shock is proposed, which seems more accurate than preceding models, comparing with numerical and experimental data.

Testing Analytical Models Using Archival or Experimental Methods

2012 ◽  
Vol 27 (1) ◽  
pp. 129-139 ◽  
Author(s):  
Shane S. Dikolli ◽  
John H. Evans ◽  
Jeffrey Hales ◽  
Michal Matejka ◽  
Donald V. Moser ◽  
...  
Keyword(s):  
Experimental Data ◽  
Empirical Research ◽  
Analytical Model ◽  
Empirical Data ◽  
Review Process ◽  
Experimental Methods ◽  
Analytical Models ◽  
Journal Review ◽  
Advantages And Disadvantages ◽  
Jel Classifications

SYNOPSIS Analytical models can quite naturally complement empirical data, whether archival or experimental. This article begins by discussing the advantages and disadvantages of combining an analytical model with archival or experimental data in a single study. We next describe how models are typically used in empirical research and discuss when including an analytical model is more versus less useful. Finally, we offer examples of more and less successful combinations of analytical models and empirical data, along with a brief discussion of how such studies are likely to fare in the journal review process. JEL Classifications: C02; C51; C99.

scholarly journals Development of an information and analytical model of soils based on X-ray fluorescence analysis

2021 ◽  
Vol 282 ◽  
pp. 07016
Author(s):  
E.M. Basarygina ◽  
N.A. Pakhomova ◽  
O.E. Akulich
Keyword(s):  
Experimental Data ◽  
Trace Elements ◽  
Analytical Model ◽  
Chemical Elements ◽  
Fluorescence Analysis ◽  
Analytical Models ◽  
Soil Reclamation ◽  
X Ray ◽  
Fallow Lands ◽  
Chelyabinsk Region

The purpose of the research was to build information and analytical models of the soil based on the data of energy-dispersive X-ray fluorescence analysis. For the soil of the Chelyabinsk region, on the basis of experimental data, information and analytical models are constructed, showing a complete list of chemical elements and trace elements, the content of which exceeds the permissible concentration. These models, which clearly reflect the content of micro-and macronutrients in the soil, are recommended for use in the development of measures for soil reclamation and the involvement of fallow lands in agricultural turnover.

Analytical Modelling of I-V Characteristics for 4H-SiC Enhancement Mode VJFET

2006 ◽  
Vol 527-529 ◽  
pp. 1195-1198
Author(s):  
Praneet Bhatnagar ◽  
Alton B. Horsfall ◽  
Nicolas G. Wright ◽  
C. Mark Johnson ◽  
Konstantin Vassilevski ◽  
...  
Keyword(s):  
Experimental Data ◽  
Finite Element ◽  
Analytical Model ◽  
Computational Efficiency ◽  
Analytical Models ◽  
Analysis Tool ◽  
Power Devices ◽  
Enhancement Mode ◽  
High Computational Efficiency ◽  
Single Set

Physics-based analytical models are seen as an efficient way of predicting the characteristics of power devices since they can achieve high computational efficiency and may be easily calibrated using parameters obtained from experimental data. This paper presents an analytical model for a 4H-SiC Enhancement Mode Vertical JFET (VJFET), based on the physics of this device. The on-state and blocking behaviour of VJFETs with finger widths ranging from 1.6+m to 2.2+m are studied and compared with the results of finite element simulations. It is shown that the analytical model is capable of accurately predicting both the on-state and blocking characteristics from a single set of parameters, underlining its utility as a device design and circuit analysis tool.

scholarly journals Modelling Early Age Shrinkage of Concrete

2019 ◽  
Vol 8 (2) ◽  
pp. 3530-3540
Keyword(s):  
Experimental Data ◽  
Comparative Study ◽  
Analytical Model ◽  
Probabilistic Analysis ◽  
Autogenous Shrinkage ◽  
Analytical Models ◽  
Early Age ◽  
Review Of Literature ◽  
Cement Ratio ◽  
Concrete Mixtures

During past decades the concrete has been developed by low water-cement ratio, addition of superplasticizer etc to improve the properties and lifetime of a structure. Despite of the imporved properties it introduces the shrinkage which leads to cracks and reduces serviceability and durability of structure or material. Therefore the study of shrinkage becomes a challenge. In this study, the autogenous shrinkage of concrete mixtures at early age is modelled using analytical models for different water-cement ratios for different ages. The main objectives of the study are review of literature on autogenous shrinkage of concrete, comparative study of different models for autogenous shrinkage of concrete using experimental data available in literature, Identification/development of an analytical model for prediction of autogenous shrinkage of concrete, and probabilistic analysis of the autogenous shrinkage are discussed

scholarly journals Novel Structure and Thermal Design and Analysis for CubeSats in Formation Flying

Aerospace ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 150
Author(s):  
Yeon-Kyu Park ◽  
Geuk-Nam Kim ◽  
Sang-Young Park
Keyword(s):  
Analytical Model ◽  
Formation Flying ◽  
Thermal Environment ◽  
Thermal Analyses ◽  
Thermal Design ◽  
Analytical Models ◽  
Test Results ◽  
Solar Panels ◽  
Novel Structure ◽  
Micro Propulsion

The CANYVAL-C (CubeSat Astronomy by NASA and Yonsei using a virtual telescope alignment for coronagraph) is a space science demonstration mission that involves taking several images of the solar corona with two CubeSats—1U CubeSat (Timon) and 2U CubeSat (Pumbaa)—in formation flying. In this study, we developed and evaluated structural and thermal designs of the CubeSats Timon and Pumbaa through finite element analyses, considering the nonlinearity effects of the nylon wire of the deployable solar panels installed in Pumbaa. On-orbit thermal analyses were performed with an accurate analytical model for a visible camera on Timon and a micro propulsion system on Pumbaa, which has a narrow operating temperature range. Finally, the analytical models were correlated for enhancing the reliability of the numerical analysis. The test results indicated that the CubeSats are structurally safe with respect to the launch environment and can activate each component under the space thermal environment. The natural frequency of the nylon wire for the deployable solar panels was found to increase significantly as the wire was tightened strongly. The conditions of the thermal vacuum and cycling testing were implemented in the thermal analytical model, which reduced the differences between the analysis and testing.

Convective Losses From Cavity Solar Receivers—Comparisons Between Analytical Predictions and Experimental Results

1983 ◽  
Vol 105 (1) ◽  
pp. 29-33 ◽  
Author(s):  
A. M. Clausing
Keyword(s):  
Experimental Data ◽  
Experimental Evidence ◽  
Analytical Model ◽  
Excellent Agreement ◽  
Experimental Results ◽  
Simple Analytical Model ◽  
Refined Model ◽  
Wall Area

Cavity solar receivers are generally believed to have higher thermal efficiencies than external receivers due to reduced losses. A simple analytical model was presented by the author which indicated that the ability to heat the air inside the cavity often controls the convective loss from cavity receivers. Thus, if the receiver contains a large amount of inactive hot wall area, it can experience a large convective loss. Excellent experimental data from a variety of cavity configurations and orientations have recently become available. These data provided a means of testing and refining the analytical model. In this manuscript, a brief description of the refined model is presented. Emphasis is placed on using available experimental evidence to substantiate the hypothesized mechanisms and assumptions. Detailed comparisons are given between analytical predictions and experimental results. Excellent agreement is obtained, and the important mechanisms are more clearly delineated.

Qualitative Discussion of Influences of some Factors on the Occurrence of Wind-Driven Coastal Upwelling Associated with “Aoshio” on the Northeast Shore of Tokyo Bay Using the Developed Analytical Model

2014 ◽  
Vol 641-642 ◽  
pp. 1040-1045
Author(s):  
Zhong Fan Zhu
Keyword(s):  
Analytical Model ◽  
Wind Shear ◽  
Coastal Upwelling ◽  
Tokyo Bay ◽  
Interfacial Friction ◽  
Observation Data ◽  
Shear Effect ◽  
Stratification Effect ◽  
Northeasterly Wind ◽  
Qualitative Discussion

An analytical model based on some solutions in the context of a two-layered fluid was developed to estimate the occurrence of northeasterly wind-driven coastal upwelling associated with “Aoshio” on the northeast shore of Tokyo Bay, and its validity was verified by comparing with observation data [1]. In this study, influences of all of the factors incorporated into this analytical model (including densities and thicknesses of the upper and lower layers, the parameter expressing the influences of interfacial friction and bottom friction) on the model are analyzed. The analytical model is found to express the competition between the wind-shear effect and the stratification effect: when the former dominates over the latter, Aoshio will occur on the northeast shore of the bay. The parameter that can be used to characterize the stratification effect can be simply expressed in terms of the product of density contrast and the square of thickness of the upper layer. Using different values of this parameter corresponding to different months in the model can simply estimate in which months it is easy for Aoshio phenomenon to happen on the northeast shore of the bay, and the result is roughly consistent with an observation phenomenon that Aoshio was frequently observed on the northeast shore of the bay in September and May and relatively less observed in June and July during 1978-2010.

Sign in / Sign up

Export Citation Format

Share Document