Identification of natural gas fractured volcanic formation by using numerical inversion method

In geotechnical engineering, vertical drainage is the most economical method for accelerating the consolidation of a large area of soft ground. In this study, we analyze the viscoelasticity of the soil and the actual drainage conditions on the top surface of the soil, and then we introduce continuous drainage boundary conditions and adopt a fractional derivative model to describe the viscoelasticity of the soil. With the use of a viscoelasticity model, the governing partial differential equation for vertical drains under continuous drainage boundary conditions is obtained. With the application of the Crump numerical inversion method, the consolidation solution for vertical drains is also obtained. Further, the rationality of the proposed solution is verified by several examples. Moreover, some examples are provided to discuss the influence of interface drainage parameters on the top surface of soil and the viscoelasticity parameters of soil on the consolidation behavior of vertical drains. The proposed method can be applied in the fields of transport engineering to predict the consolidation settlement of a foundation reinforced by vertical drains.

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Numerical inversion method for the Laplace transform based on Boubaker polynomials operational matrix

International Journal of Modeling Simulation and Scientific Computing ◽

10.1142/s1793962322500106 ◽

2021 ◽

Author(s):

Rachid Belgacem ◽

Ahmed Bokhari ◽

Salih Djilali ◽

Sunil Kumar

Keyword(s):

Laplace Transform ◽

Perturbation Method ◽

Homotopy Perturbation Method ◽

Operational Matrix ◽

Inversion Method ◽

Numerical Inversion ◽

Homotopy Perturbation ◽

Boubaker Polynomials ◽

The Laplace Transform ◽

Good Agreement

We investigate through this research the numerical inversion technique for the Laplace transforms cooperated by the integration Boubaker polynomials operational matrix. The efficiency of the presented approach is demonstrated by solving some differential equations. Also, this technique is combined with the standard Laplace Homotopy Perturbation Method. The numerical results highlight that there is a very good agreement between the estimated solutions with exact solutions.

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Topological Network Inversion Method of Fire Source Location for Liquefied Natural Gas (LNG) Storage

Procedia Engineering ◽

10.1016/j.proeng.2017.12.010 ◽

2018 ◽

Vol 211 ◽

pp. 247-255 ◽

Cited By ~ 2

Author(s):

Jin-qiu Hu ◽

Rong-han Wang ◽

Lai-bin Zhang

Keyword(s):

Natural Gas ◽

Source Location ◽

Liquefied Natural Gas ◽

Inversion Method ◽

Fire Source ◽

Topological Network

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A Recent Laplace Inversion Technique Applied to a Transmission Line Problem

International Journal of Electrical Engineering Education ◽

10.1177/002072097801500308 ◽

1978 ◽

Vol 15 (3) ◽

pp. 243-246 ◽

Cited By ~ 1

Author(s):

G. Ledda ◽

N. Mullineux ◽

J. R. Reed

Keyword(s):

Transmission Line ◽

Inversion Method ◽

Numerical Inversion ◽

Orthogonal Functions ◽

Laplace Inversion ◽

Inversion Technique

A numerical inversion method employing orthogonal functions is tested on an idealized transmission line problem. The reasons for its shortcomings are qualitatively discussed.

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Fire Accident Inversion Method Base on STAMP and Topological Network for LNG Depot

Volume 7: Operations, Applications, and Components ◽

10.1115/pvp2018-85113 ◽

2018 ◽

Author(s):

Jinqiu Hu ◽

Laibin Zhang ◽

Ronghan Wang ◽

Qingchun Ma

Keyword(s):

Natural Gas ◽

Inversion Method ◽

Topological Network ◽

Optimal Estimator ◽

Method Base ◽

Fire And Explosion ◽

Lng Tank ◽

And Storage ◽

Fire Accident

Natural Gas is becoming an important energy source option and the capacity of the world to produce it is surging. Natural gas is usually liquefied for shipping and storage. Fire and explosion are among the most dangerous accidents in facilities at LNG Depot; especially pool fire is the most frequent incidents. At the same time the chain of accidents may lead to extremely severe consequences. In order to avoid such calamity a detail study on accident inversion technology is required to save human lives and prohibit the destruction of LNG Depot. In this thesis a topological network based fire accident inversion method for LNG tank fire accident is proposed. Firstly, analyze the LNG depot with the STAMP/STPA method. Then, the topology model of LNG tank fire inversion is established, and the optimal estimator of the shortest path is proposed according to the weighted edge topological network structure, based on which the fire location can be determined. Case study is applied to a LNG Depot. The results show that the position of the fire source calculated by the proposed method is the same as that of the simulated accident by FDS, which proves the feasibility of the method and provides a basis for reducing the fire losses and preventing accidents of LNG.

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Study of Testing Method for Dynamic Initiation Toughness of Sandstone under Blasting Loading

Shock and Vibration ◽

10.1155/2018/1043298 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

Dingjun Xiao ◽

Zheming Zhu ◽

Rong Hu ◽

Lin Lang

Keyword(s):

Fracture Toughness ◽

Blast Hole ◽

Fracture Initiation ◽

Strain Gauges ◽

Inversion Method ◽

Numerical Inversion ◽

Initiation Toughness ◽

Type I ◽

Initiation Fracture Toughness ◽

Sandstone Specimen

In this paper, an internal central single-cracked disk (ICSCD) specimen was proposed for the study of dynamic fracture initiation toughness of sandstone under blasting loading. The ICSCD specimen had a diameter of 400 mm sandstone disc with a 60 mm long crack. Blasting tests were conducted by using the ICSCD specimens. The blasting strain-time curve was obtained from the radial strain gauges placed around the blast hole. The fracture initiation time was determined by circumferential strain gauges placed around the crack tip. The stress history on the blast hole of the sandstone specimen was then derived from measured strain curve through the Laplace transform. The numerical solutions were further obtained by the numerical inversion method. A numerical model was established using the finite element software ANSYS. The type I dynamic stress intensity factor curves of sandstone under blasting loading were derived by the mutual interaction integration method. The results showed that (1) the ICSCD specimen can be used to measure dynamic initiation fracture toughness of rocks; (2) the stress on the blast hole wall can be obtained by the Laplace numerical inversion method; (3) the dynamic initiation fracture toughness of the ICSCD sandstone specimen can be calculated by the experimental-numerical method with a maximum error of only 7%.

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