An inverse approach integrating flowmeter and pumping test data for three-dimensional aquifer characterization

This paper describes analyses of a railroad tank car impacted at its side by a ram car with a rigid punch. This generalized collision, referred to as a shell impact, is examined using nonlinear (i.e., elastic-plastic) finite element analysis (FEA) and three-dimensional (3-D) collision dynamics modeling. Moreover, the analysis results are compared to full-scale test data to validate the models. Commercial software packages are used to carry out the nonlinear FEA (ABAQUS and LS-DYNA) and the 3-D collision dynamics analysis (ADAMS). Model results from the two finite element codes are compared to verify the analysis methodology. Results from static, nonlinear FEA are compared to closed-form solutions based on rigid-plastic collapse for additional verification of the analysis. Results from dynamic, nonlinear FEA are compared to data obtained from full-scale tests to validate the analysis. The collision dynamics model is calibrated using test data. While the nonlinear FEA requires high computational times, the collision dynamics model calculates gross behavior of the colliding cars in times that are several orders of magnitude less than the FEA models.

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Semi-analytical solution to pumping test data with barrier, wellbore storage, and partial penetration effects

Engineering Geology ◽

10.1016/j.enggeo.2017.05.011 ◽

2017 ◽

Vol 226 ◽

pp. 44-51 ◽

Cited By ~ 72

Author(s):

Yong-Xia Wu ◽

Jack Shuilong Shen ◽

Wen-Chieh Cheng ◽

Takenori Hino

Keyword(s):

Analytical Solution ◽

Test Data ◽

Pumping Test ◽

Partial Penetration ◽

Wellbore Storage

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Analysis and Inversion of Contact Stress for the Finite Thickness Neo-Hookean Layer

Journal of Applied Mechanics ◽

10.1115/1.4040598 ◽

2018 ◽

Vol 85 (10) ◽

Cited By ~ 10

Author(s):

Heng Yang ◽

Xue-Feng Yao ◽

Shen Wang ◽

Yu-Chao Ke ◽

Sheng-Hao Huang ◽

...

Keyword(s):

Contact Stress ◽

Contact Surface ◽

Finite Thickness ◽

Three Dimensional ◽

Image Correlation ◽

Rubber Layer ◽

Inverse Approach ◽

Element Simulation ◽

Loading Modes ◽

Nonlinear Finite Element Simulation

In this paper, the theoretical analysis and the inversion of the contact stress on the finite thickness rubber contact surface with the friction effect are investigated. First, an explicit expression of deformation and stress on the surface of rubber under a rigid spherical indenter is developed by means of theoretical model, dimensional analysis, and nonlinear finite element simulation. Second, the inverse approach for obtaining the contact stress on the finite thickness rubber contact surface is presented and verified theoretically. Also, the displacement, the stress field, and the friction coefficient are obtained by means of three-dimensional digital image correlation (3D DIC) method. Finally, the applicability to other hyperelastic models, general boundary conditions, and loading modes are discussed. The results will provide an important theoretical and experimental basis for evaluating the contact stress on the finite thickness rubber layer.

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Estimation of Transmissivity and Permeability in Swedish Bedrock

Hydrology Research ◽

10.2166/nh.1977.0009 ◽

1977 ◽

Vol 8 (2) ◽

pp. 103-116 ◽

Cited By ~ 13

Author(s):

Leif Carlsson ◽

Anders Carlstedt

Keyword(s):

Statistical Analysis ◽

Test Data ◽

Hydraulic Properties ◽

Pumping Test ◽

Crystalline Rocks ◽

Wide Range ◽

Well Loss

Statistical analysis of pumping-test data from wells have been used to calculate average values of transmissivity and permeability in different Swedish rocks. The influence of the well-loss on the calculations is discussed. The highest values of transmissivity and permeability of the investigated rocks are found in the sandstones of Algonkian and Cambrian age. The Archean crystalline rocks show a wide range of results, and of the investigated rocks the gneisses seem to be more permeable than the granites. However, the degree of tectonization affects the hydraulic properties of the rocks considerably.

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