scholarly journals An Integrated Modeling Scheme For Characterizing 3D Hydrogeological Heterogeneity of The New Jersey Shelf

Author(s):  
Ariel Tremayne Thomas ◽  
Jan von Harten ◽  
Tomi Adriansyah Jusri ◽  
Sönke Reiche ◽  
Florian Wellmann

Abstract Continental shelves around the globe are hosts to vast reservoirs of offshore freshened groundwater. These systems show considerable complexity, often as a function of the geological heterogeneity. Data needed to characterise these systems are often sparse, and numerical models rely on generalized simplifications of the geological environment. In order to improve our understanding of these systems, it is necessary to implement modeling approaches that can produce large-scale geologically representative models using sparse data. We present an interdisciplinary stochastic modeling workflow incorporating borehole data, 2D depth-migrated seismic profiles, seismic attributes, and prior knowledge of the depositional setting. We generate a conditioned Gaussian field of porosity on the New Jersey shelf. We also perform a petrophysical conversion to a corresponding permeability distribution. The model dimensions are 134 km x 69 km x 1.7 km, with an adjustable resolution that can be adapted for process-based models of flow and solute transport. The integrated approach successfully translates small-scale porosity variations to a shelf-scale model that honors key characteristics of the New Jersey shelf wave-dominated depositional environment. The model was generated using open-source packages. All data and code to reproduce the complete workflow are provided along with this study so the model can be reproduced at any resolution for further studies of continental shelf processes offshore New Jersey.

SPE Journal ◽  
2019 ◽  
Vol 24 (04) ◽  
pp. 1508-1525
Author(s):  
Mengbi Yao ◽  
Haibin Chang ◽  
Xiang Li ◽  
Dongxiao Zhang

Summary Naturally or hydraulically fractured reservoirs usually contain fractures at various scales. Among these fractures, large-scale fractures might strongly affect fluid flow, making them essential for production behavior. Areas with densely populated small-scale fractures might also affect the flow capacity of the region and contribute to production. However, because of limited information, locating each small-scale fracture individually is impossible. The coexistence of different fracture scales also constitutes a great challenge for history matching. In this work, an integrated approach is proposed to inverse model multiscale fractures hierarchically using dynamic production data. In the proposed method, a hybrid of an embedded discrete fracture model (EDFM) and a dual-porosity/dual-permeability (DPDP) model is devised to parameterize multiscale fractures. The large-scale fractures are explicitly modeled by EDFM with Hough-transform-based parameterization to maintain their geometrical details. For the area with densely populated small-scale fractures, a truncated Gaussian field is applied to capture its spatial distribution, and then the DPDP model is used to model this fracture area. After the parameterization, an iterative history-matching method is used to inversely model the flow in a fractured reservoir. Several synthetic cases, including one case with single-scale fractures and three cases with multiscale fractures, are designed to test the performance of the proposed approach.


2013 ◽  
Vol 14 (2) ◽  
Author(s):  
Noor Fachrizal

Biomass such as agriculture waste and urban waste are enormous potency as energy resources instead of enviromental problem. organic waste can be converted into energy in the form of liquid fuel, solid, and syngas by using of pyrolysis technique. Pyrolysis process can yield higher liquid form when the process can be drifted into fast and flash response. It can be solved by using microwave heating method. This research is started from developing an experimentation laboratory apparatus of microwave-assisted pyrolysis of biomass energy conversion system, and conducting preliminary experiments for gaining the proof that this method can be established for driving the process properly and safely. Modifying commercial oven into laboratory apparatus has been done, it works safely, and initial experiments have been carried out, process yields bio-oil and charcoal shortly, several parameters are achieved. Some further experiments are still needed for more detail parameters. Theresults may be used to design small-scale continuous model of productionsystem, which then can be developed into large-scale model that applicable for comercial use.


2000 ◽  
Vol 663 ◽  
Author(s):  
J. Samper ◽  
R. Juncosa ◽  
V. Navarro ◽  
J. Delgado ◽  
L. Montenegro ◽  
...  

ABSTRACTFEBEX (Full-scale Engineered Barrier EXperiment) is a demonstration and research project dealing with the bentonite engineered barrier designed for sealing and containment of waste in a high level radioactive waste repository (HLWR). It includes two main experiments: an situ full-scale test performed at Grimsel (GTS) and a mock-up test operating since February 1997 at CIEMAT facilities in Madrid (Spain) [1,2,3]. One of the objectives of FEBEX is the development and testing of conceptual and numerical models for the thermal, hydrodynamic, and geochemical (THG) processes expected to take place in engineered clay barriers. A significant improvement in coupled THG modeling of the clay barrier has been achieved both in terms of a better understanding of THG processes and more sophisticated THG computer codes. The ability of these models to reproduce the observed THG patterns in a wide range of THG conditions enhances the confidence in their prediction capabilities. Numerical THG models of heating and hydration experiments performed on small-scale lab cells provide excellent results for temperatures, water inflow and final water content in the cells [3]. Calculated concentrations at the end of the experiments reproduce most of the patterns of measured data. In general, the fit of concentrations of dissolved species is better than that of exchanged cations. These models were later used to simulate the evolution of the large-scale experiments (in situ and mock-up). Some thermo-hydrodynamic hypotheses and bentonite parameters were slightly revised during TH calibration of the mock-up test. The results of the reference model reproduce simultaneously the observed water inflows and bentonite temperatures and relative humidities. Although the model is highly sensitive to one-at-a-time variations in model parameters, the possibility of parameter combinations leading to similar fits cannot be precluded. The TH model of the “in situ” test is based on the same bentonite TH parameters and assumptions as for the “mock-up” test. Granite parameters were slightly modified during the calibration process in order to reproduce the observed thermal and hydrodynamic evolution. The reference model captures properly relative humidities and temperatures in the bentonite [3]. It also reproduces the observed spatial distribution of water pressures and temperatures in the granite. Once calibrated the TH aspects of the model, predictions of the THG evolution of both tests were performed. Data from the dismantling of the in situ test, which is planned for the summer of 2001, will provide a unique opportunity to test and validate current THG models of the EBS.


2015 ◽  
Vol 2 (2) ◽  
pp. 513-536 ◽  
Author(s):  
I. Grooms ◽  
Y. Lee

Abstract. Superparameterization (SP) is a multiscale computational approach wherein a large scale atmosphere or ocean model is coupled to an array of simulations of small scale dynamics on periodic domains embedded into the computational grid of the large scale model. SP has been successfully developed in global atmosphere and climate models, and is a promising approach for new applications. The authors develop a 3D-Var variational data assimilation framework for use with SP; the relatively low cost and simplicity of 3D-Var in comparison with ensemble approaches makes it a natural fit for relatively expensive multiscale SP models. To demonstrate the assimilation framework in a simple model, the authors develop a new system of ordinary differential equations similar to the two-scale Lorenz-'96 model. The system has one set of variables denoted {Yi}, with large and small scale parts, and the SP approximation to the system is straightforward. With the new assimilation framework the SP model approximates the large scale dynamics of the true system accurately.


2019 ◽  
Vol 111 ◽  
pp. 01045
Author(s):  
Matei-Razvan Georgescu ◽  
Ilinca Nastase ◽  
Amina Meslem ◽  
Mihnea Sandu ◽  
Florin Bode

An attempt at improving the ventilation solution for the crew quarters aboard the International Space Station requires a thorough understanding of the flow dynamics in a microgravity environment. An experimental study is required in order to validate the numerical models. As part of this process, a small-scale model was proposed for a detailed study of the velocity field. PIV measurements in water offer high quality results and were chosen for the subject. Following certain similitude criteria, an equivalence can be found between the results of these measurements and the real ventilation scenario. This paper describes the development process of this small-scale model as well as its performance in the initial test runs. Details regarding the advantages and weaknesses of this first model are the core of the paper, with the intention of aiding researchers in their design of similar models. The conclusion presents future steps and proposed improvements to the model.


Author(s):  
Hiroaki Takegami ◽  
Atsuhiko Terada ◽  
Kaoru Onuki ◽  
Ryutaro Hino

The Japan Atomic Energy Agency has been conducting R&D on thermochemical water-splitting Iodine-Sulfur (IS) process for hydrogen production to meet massive demand in the future hydrogen economy. A concept of sulfuric acid decomposer was developed featuring a heat exchanger block made of SiC. Recent activity has focused on the reliability assessment of SiC block. Although knowing the strength of SiC block is important for the reliability assessment, it is difficult to evaluate a large-scale ceramics structure without destructive test. In this study, a novel approach for strength estimation of SiC structure was proposed. Since accurate strength estimation of individual ceramics structure is difficult, a prediction method of minimum strength in the structure of the same design was proposed based on effective volume theory and optimized Weibull modulus. Optimum value of the Weibull modulus was determined for estimating the lowest strength. The strength estimation line was developed by using the determined modulus. The validity of the line was verified by destructive test of SiC block model, which is small-scale model of the SiC block. The fracture strength of small-scale model satisfied the predicted strength.


Author(s):  
Daniel F. Walczyk ◽  
Seungryeol Yoo

Profiled Edge Laminae (PEL) tooling is a thick-layer Rapid Tooling (RT) method that was developed a decade ago. Even with demonstrable advantages for large-scale tool applications over conventional CNC-machining of a solid billet and other commercially available RT methods, PEL tooling has not seen widespread use by industry because prior research related to laminated tooling has (1) focused on small-scale tools and perpendicular laser-cutting that required extensive surface finishing, and (2) there is no integrated and practical design and fabrication approach to tooling development. This paper describes a more streamlined and integrated approach to PEL tooling development, called the PEL Process, that builds upon prior work in this area. Critical components of the process that are described in detail include how to obtain lamina slicing information directly from a CAD model of the intended tool surface, how to measure dimensional errors between the PEL and CAD tool surfaces, and improved Abrasive Waterjet cutting trajectory and laminae slicing algorithms. The PEL Process is then demonstrated for the design and fabrication of aluminum PEL tooling used for hydroforming aircraft sheet metal components.


Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 701 ◽  
Author(s):  
Lorenzo Sallustio ◽  
Marco di Cristofaro ◽  
Maaz Hashmi ◽  
Matteo Vizzarri ◽  
Tommaso Sitzia ◽  
...  

Land use by humans strongly alters the landscape mosaic, either by reducing or increasing its heterogeneity. One of the most recent and widespread land use changes in Europe has been the spontaneous reforestation of marginal agricultural lands. These primarily affected small landscape patches, such as trees outside forests (TOF) and small open areas (SOA), often represent the most diversifying features of landscape’ structures. Nevertheless, only small-scale studies can be found in the literature and thus it remains a relatively unexplored issue. Integrating inventory and cartographic approaches, this work assesses changes in abundance, coverage, and average size of small patches in Italy between 1990 and 2013. Main results showed an overall increase in number and coverage of small patches during the reference period. The average patch size remains unaltered for TOF but decreases significantly for SOA, due to trees encroachment and canopy cover increasing in forests. Our findings confirm the important changes in Mediterranean land mosaics and contribute to a better understanding of current conditions and recent trends regarding TOF and SOA. The integrated approach has proven to be helpful for the large-scale assessment of small patches dynamics, representing a viable monitoring tool to encourage the inclusion of small patches in landscape policy and planning.


2020 ◽  
Vol 104 (2) ◽  
pp. 1581-1596
Author(s):  
Thomas Heinze

Abstract Dynamics of snow avalanches or landslides can be described by rapid granular flow. Experimental investigations of granular flow at laboratory scale are often required to analyze flow behaviour and to develop adequate mathematical and numerical models. Most investigations use image-based analysis, and additional sensors such as pressure gauges are not always possible. Testing various scenarios and parameter variations such as different obstacle shapes and positions as well as basal topography and friction usually requires either the construction of a new laboratory setups for each test or a cumbersome reconstruction. In this work, a highly flexible and modular laboratory setup is presented based on LEGO bricks. The flexibility of the model is demonstrated, and possible extensions for future laboratory tests are outlined. The setup is able to reproduce published laboratory experiments addressing current scientific research topics, such as overflow of a rigid reflector, flow on a bumpy surface and against a rigid wall using standard image-based analysis. This makes the setup applicable for quick scenario testing, e.g. for hypothesis testing or for low-cost testing prior to large-scale experiments, and it can contribute to the validation of external results and to benchmarks of numerical models. Small-scale laboratory setups are also very useful for demonstration purposes such as education and public outreach, both crucial in the context of natural hazards. The presented setup enables variation of parameters such as of slope length, channel width, height and shape, inclination, bed friction, obstacle position and shape, as well as density, composition, amount and grain size of flowing mass. Observable quantities are flow type, flow height, flow path and flow velocity, as well as runout distance, size and shape of the deposited material. Additional sensors allow further quantitative assessments, such as local pressure values.


2006 ◽  
Vol 41 (1) ◽  
pp. 24-36 ◽  
Author(s):  
Karl-Erich Lindenschmidt ◽  
René Wodrich ◽  
Cornelia Hesse

Abstract A hypothesis stating that more complex descriptions of processes in models simulate reality better (less error) but with more unreliable predictability (more sensitivity) is tested using a river water quality model. This hypothesis was extended stating that applying the model on a domain of smaller scale requires greater complexity to capture the same accuracy as in large-scale model applications which, however, leads to increased model sensitivity. The sediment and pollutant transport model TOXI, a module in the WASP5 package, was applied to two case studies of different scale: a 90-km course of the 5th order (sensu Strahler 1952) lower Saale river, Germany (large scale), and the lock-and-weir system at Calbe (small scale) situated on the same river course. A sensitivity analysis of several parameters relating to the physical and chemical transport processes of suspended solids, chloride, arsenic, iron and zinc shows that the coefficient, which partitions the total heavy metal mass into its dissolved and sorbed fraction, is a very sensitive parameter. Hence, the complexity of the sorptive process was varied to test the hypotheses.


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