scholarly journals A Coupled One-Dimensional Numerical Simulation of the Land Subsidence Process in a Multilayer Aquifer System due to Hydraulic Head Variation in the Pumped Layer

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Ye Wang ◽  
Mao-sheng Zhang ◽  
Fu-sheng Hu ◽  
Ying Dong ◽  
Kun Yu
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Land Subsidence ◽  
Transition Period ◽  
Pressure Head ◽  
Hydraulic Head ◽  
Confined Aquifer ◽  
One Dimensional ◽  
Aquifer System ◽  
Simulation Results

After exploitation of groundwater had been reduced and the groundwater level of the confined aquifer had risen, land subsidence was observed to continue rather than cease for several years according to the layer-wise mark monitoring data in Xi’an. To analyze the phenomena, a numerical model of a coupled one-dimensional multilayer aquifer system is developed to represent land subsidence due to hydraulic head variation in the pumped layer. The numerical simulation results show that the pressure head in other layers does not rise immediately when the hydraulic head in the pumped layer starts to recover after pumping ceases. In addition, after the pumping is stopped, a dividing point can be found in aquitards next to the pumped layer, with the aquitards being divided into two parts: a compressed part and a rebounding part. The dividing points move toward the side and away from the pumped layer with the transferring of pore pressure in the aquitard. The results of the simulation also show that there is a transition period between land subsidence and rebound. In this transition period, land could continue to subside even though the hydraulic head in the pumped layer begins to recover.

scholarly journals NUMERICAL SIMULATION OF TSUNAMI CURRENTS

2011 ◽  
Vol 1 (32) ◽  
pp. 6 ◽  
Author(s):  
Eizo Nakaza ◽  
Tsunakiyo Iribe ◽  
Muhammad Abdur Rouf
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Open Channel ◽  
Implicit Method ◽  
Simulation Results ◽  
Moving Particle ◽  
Fixed Structure ◽  
Tsunami Currents

The paper aims to simulate Tsunami currents around moving and fixed structures using the moving-particle semi-implicit method. An open channel with four different sets of structures is employed in the numerical model. The simulation results for the case with one structure indicate that the flow around the moving structure is faster than that around the fixed structure. The flow becomes more complex for cases with additional structures.

Study on the Forming Process of the Crossmember in Car Intermediate Floor

2013 ◽  
Vol 442 ◽  
pp. 593-598
Author(s):  
Xue Xia Wang ◽  
Peng Chong Guan ◽  
Hai Peng Li ◽  
Li Hui Wang ◽  
Na Zhang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Process Parameters ◽  
Thickness Distribution ◽  
Forming Limit Diagram ◽  
Forming Limit ◽  
Simulation Technology ◽  
Forming Process ◽  
Distribution Diagram ◽  
Simulation Results

Flanging and bending forming processes of the crossmember in car intermediate floor are investigated respectively by using numerical simulation technology. The numerical model of the crossmember was established and its press forming effect was simulated to determine the feasible process parameters affecting its manufacturability. Forming limit diagram and thickness distribution diagram are used to evaluate simulation results of different process schemes. And then optimum values of process parameters for flanging and bending are found, which can reduce the tendencies of wrinkling, springback and crackling during the stamping of the product.

The Optimization of Vibration Induced by a V6 Engine Cooling Module

2011 ◽  
Author(s):  
Ji Yang ◽  
Zhiyong Hao ◽  
Ruwei Ge ◽  
Liansheng Wang ◽  
Kang Zheng
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Automotive Industry ◽  
Optimization Design ◽  
Working Condition ◽  
Steering Wheel ◽  
Engine Cooling ◽  
Simulation Results ◽  
Cooling Module ◽  
Specific Working

The engine cooling module consists of condenser, radiator and fan (CRFM), which has long been recognized as a main source of sound and vibration in the automotive industry. As the engine becomes increasingly compact and powerful, customers gradually have higher expectations for automobile NVH performance than ever before. Thus the reduction of noise and vibration induced by CRFM becomes critical, which can greatly influence overall NVH performance. Combined with experimental and numerical methods, this paper focuses on the identification and optimization of steering wheel (SW) vibration induced by CRFM for a vehicle with V6 engine while engine idling. The numerical model established in this paper, based on Matlab and taking chassis vibration into account, can predict and optimize the vibration of CRFM under specific working condition with the help of energy decoupling and Newmark-Beta methodology. The optimization design of CRFM mainly involves the stiffness, position and angle of isolators. The numerical simulation results are validated experimentally, which can help further design of CRFM.

Numerical Simulation on Hydrogen Dispersion in Automobiles due to Storage Cylinder Failure

2011 ◽  
Author(s):  
Yan-Lei Liu ◽  
Jin-Yang Zheng ◽  
Shu-Xin Han ◽  
Yong-Zhi Zhao
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Numerical Model ◽  
Hydrogen Sensor ◽  
High Concentration ◽  
Concentration Region ◽  
Species Transport ◽  
Safety Design ◽  
Simulation Results

A numerical model for dispersion of hydrogen in hydrogen powered automobiles was established basing on finite element method with species transport and reaction module of FLUENT. And corresponding numerical simulations were done in order to analysis the dispersion of hydrogen due to leakage from different position of the storage cylinder on the automobiles. Also, the distribution of the hazard region due to hydrogen dispersion was obtained. The simulation results show that the baffle above the cylinder can accumulate the hydrogen. Therefore, the high concentration region of hydrogen exists near the baffle. The study can provide reference for hydrogen sensor placement and safety design of hydrogen powered automobiles.

Numerical Simulation of Different Schemes’ Influence on Coastal Areas for Groundwater-Source Heat Pump Engineering

2012 ◽  
Vol 588-589 ◽  
pp. 1278-1281
Author(s):  
Jun Pan ◽  
Shi Xiao Li ◽  
Chang Liu ◽  
Yang Li
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Groundwater Flow ◽  
Solute Transport ◽  
Heat Pump ◽  
Seawater Intrusion ◽  
Underground Water ◽  
Coastal Areas ◽  
Simulation Results ◽  
Groundwater Source

More and more people have take more attention on the problem like Seawater intrusion, The same floor recharge and "heat transfixion". This article has established the groundwater flow and solute transport and temperature coupling numerical model,to simulate the underground water temperature’s change by changing the wells’ spacing manner. Simulation results show that the two kinds of disposing Wells solutions are not cause seawater invasion, the second disposing Wells scheme help to prevent the occurrence of seawater invasion.

Multi-layered diffusive convection. Part 2. Dynamics of layer evolution

2010 ◽  
Vol 651 ◽  
pp. 465-481 ◽  
Author(s):  
TAKASHI NOGUCHI ◽  
HIROSHI NIINO
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Direct Numerical Simulation ◽  
Analytical Model ◽  
The Other ◽  
One Dimensional ◽  
Turbulent Entrainment ◽  
Diffusive Convection ◽  
Two Component

Evolution of layers in an unbounded diffusively stratified two-component fluid and its dynamics are studied by means of a direct numerical simulation (DNS) and an analytical model. The numerical simulation shows that the layers grow by repeating mergings with the neighbouring layers. By analysing the results of the numerical simulation, the mechanism of the merging is examined in detail. Two modes of merging are found to exist: one is the layer vanishing mode and the other is the interface vanishing mode. The vanishings of layers and interfaces are caused by turbulent entrainment at the interfaces. Based on the analysis of the numerical model, a one-dimensional asymmetric entrainment model is proposed. In the model, each layer is assumed to interact with its neighbouring layers through simplified convective entrainment laws. The model is applied to two simple configurations of layers and is proved to reproduce the layer evolutions found in the DNS successfully.

scholarly journals Analytical assessment of subsidence due to Aquifer Storage and Recovery (ASR) applications to multi-aquifer systems

2000 ◽  
Vol 21 ◽  
Author(s):  
J. Li
Keyword(s):  
Analytical Solution ◽  
Land Subsidence ◽  
Potential Risk ◽  
Aquifer Storage And Recovery ◽  
One Dimensional ◽  
Aquifer System ◽  
Aquifer Storage ◽  
Aquifer Systems ◽  
The One ◽  
Development And Management

The present paper emphasises concerns of land subsidence or compression of clay confining beds caused by periodic withdrawal and injection of water from or into the adjacent aquifers. An analytical solution for a one-dimensional case based on a sandwich model is found so that analysis of potential risk of aquifer system deformation due to the technology of Aquifer Storage and Recovery (ASR) can be conducted. A governing equation expressed directly in terms of displacement is employed to describe the one-dimensional subsidence. For simplicity, saturated aquifer systems are assumed to behave like poroelastic material. A cyclic loading function with a triangle pattern is assumed at boundaries to simulate effective stress induced by changes in hydraulic head at boundaries. The both compression and swelling of clay due to the periodic and linear loads at the boundaries are considered in this model. The two aquifers (one above the confining bed and the other beneath) can be pumped independently of each other. The results from the analytical solution are applied to estimate and predict potential risk of land subsidence due to ASR activity and to provide a first-estimate type of guideline for city or regional development and management of water resources.

scholarly journals The Accuracy of the RK-4 and RK-5 Technique as a Numerical Solution to the SEIRS Model of Online Game Addiction on Mathematics Students

2021 ◽  
Vol 2123 (1) ◽  
pp. 012005
Author(s):  
Syafruddin Side ◽  
Abdul Saman ◽  
Nur Rezky Ramadhan ◽  
Sahlan Sidjara
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Quantitative Research ◽  
Secondary Data ◽  
Online Games ◽  
Mathematics Students ◽  
Online Game ◽  
Game Addiction ◽  
Simulation Results ◽  
Runge Kutta

Abstract This study aims to determine the accuracy of Runge kutta order-4 (RK-4) and order-5 (RK-4) as a solution to the SEIRS numerical model for online game addiction in mathematics students at Universitas Negeri Makassar. The model used in online game addiction is the Suspected-Exposed-Infected-Recovered-Suspected (SEIRS). This is a quantitative research with secondary data obtained from a closed questionnaire where students were given several answer choices. It starts by examining the SEIRS model of online game addiction, before determining general solutions using the RK-4 and RK-5 techniques. The model is then analyzed and simulated using RK-4 and RK-5 techniques, which are compared to determine the most accurate one. The results show that the SEIRS simulation model is accurate for predicting the number of online game addictions. Furthermore, the Runge-Kutta technique can be used to observe the trend of increasing cases of online games among students. The numerical simulation showed that the RK-4 technique is more accurate than the RK-5 when the population is larger. The simulation results of the SEIRS model using MAPLE provided an estimated increase in online game addiction that can be used by students and their parents to limit the number of permits associated with launching online games.

scholarly journals Analytical Solution of Tidal Loading Effect in a Submarine Leaky Confined Aquifer System

Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-15
Author(s):  
Zongzhong Song ◽  
Hailong Li ◽  
Qian Ma ◽  
Chunmiao Zheng ◽  
Jiu Jimmy Jiao ◽  
...  
Keyword(s):  
Analytical Solution ◽  
Confined Aquifer ◽  
One Dimensional ◽  
Aquifer System ◽  
Groundwater Level Fluctuations ◽  
Groundwater Head ◽  
Aquifer Systems ◽  
Groundwater Fluctuation ◽  
Loading Effects ◽  
Tidal Loading

Although there are many existing analytical studies of tidal groundwater level fluctuations in coastal aquifer systems, few of them focus on an offshore submarine aquifer. Here, we consider tidal groundwater head fluctuations in a submarine leaky confined aquifer overlain by a semipermeable seabed. Both the seabed and the confined aquifer are assumed to extend horizontally infinitely. A one-dimensional mathematical model is established to describe the problem, and the analytical solution is derived. The impacts of the tidal loading efficiency, hydraulic conductivity and elastic storage of the semipermeable layer and aquifer on the groundwater head fluctuations in the aquifer system are analyzed and discussed. Solution analyses indicated that tidal loading effects tend to enhance the amplitude of the tidal groundwater fluctuation in the confined aquifer system and to reduce the phase shift between the groundwater head and the sea tide fluctuations.

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