A three‐dimensional numerical model investigation of the impact of submerged macrophytes on flow dynamics in a large fluvial lake

2019 ◽  
Vol 64 (9) ◽  
pp. 1627-1642 ◽  
Author(s):  
Maxim Bulat ◽  
Pascale M. Biron ◽  
Jay R. W. Lacey ◽  
Morgan Botrel ◽  
Christiane Hudon ◽  
...  
Keyword(s):  
Numerical Model ◽  
Submerged Macrophytes ◽  
Three Dimensional ◽  
Flow Dynamics ◽  
Model Investigation ◽  
Fluvial Lake ◽  
The Impact

Performance of Thermoactive Foundations for Commercial Buildings

2012 ◽  
Author(s):  
Byung Chang Kwag ◽  
Moncef Krarti
Keyword(s):  
Numerical Model ◽  
Energy Use ◽  
Three Dimensional ◽  
Thermal Response ◽  
Building Energy ◽  
Commercial Buildings ◽  
Response Factors ◽  
Testing Data ◽  
Foundation Pile ◽  
The Impact

A transient three-dimensional numerical model is developed to model the performance of thermoactive foundations used to heat and cool commercial buildings. Using laboratory testing data, the numerical model is validated and used to carry out a sensitivity analysis to assess the most important design and operating parameters that affect the performance of thermoactive foundations. It is found that the foundation depth, the shank space, the fluid flow rate, and the number of U-tube loops in each foundation pile are the main parameters that affect the thermal performance of a thermoactive foundation system. Based on the validated numerical model, thermal response factors for a thermoactive foundation are developed, and implemented into a detailed building energy simulation program. These thermal-response factors are then used to estimate the impact of installing thermoactive foundations on the total energy use of typical office buildings in various US climates.

scholarly journals Three-Dimensional Evolution of Mesoscale Anticyclones in the Lee of Crete

2020 ◽  
Vol 7 ◽  
Author(s):  
Artemis Ioannou ◽  
Alexandre Stegner ◽  
Franck Dumas ◽  
Briac Le Vu
Keyword(s):  
Numerical Model ◽  
Vertical Structure ◽  
Three Dimensional ◽  
Wind Forcing ◽  
Water Model ◽  
Mountain Range ◽  
Dynamical Process ◽  
Ekman Pumping ◽  
Spatio Temporal ◽  
The Impact

Motivated by the recurrent formation of mesoscale anticyclones in the southeast of Crete, we investigated with a high resolution model the response of the ocean to orographic wind jets driven by the Cretean mountain range. As shown in the dynamical process study of Ioannou et al. (2020) which uses a simplified shallow-water model, we confirm here, using the CROCO (Coastal and Regional Ocean COmmunity) model, that the main oceanic response to the Etesian wind forcing is the formation of mesoscale anticyclones. Moreover, we found that the intensity of the wind-induced Ekman pumping acting on the eddies, once they are formed, modulates their intensity. Among the various coastal anticyclones formed during summer and fall 2015, only one of them will correspond to a long lived structure (M_IE15) which is similar to the Ierapetra Eddy detected in 2015 (O_IE15) on the AVISO/DUACS products. Thanks to the DYNED-Atlas data base, we were able to perform a quantitative comparison of the vertical structure of such long-lived anticyclone between the numerical model and the in-situ measurements of the various Argo profilers trapped inside the eddy core. Even without assimilation or any nudging, the numerical model was able to reproduce correctly the formation period, the seasonal evolution and the vertical structure of the O_IE15. The main discrepancy between the model and the altimetry observations is the dynamical intensity of the anticyclone. The characteristic eddy velocity derived from the AVISO/DUACS product for the O_IE15 is much lower than in the numerical model. This is probably due to the spatio temporal interpolation of the AVISO/DUACS altimetry products. More surprisingly, several coastal anticyclones were also formed in the model in the lee of Crete area during summer 2015 when the Etesian winds reach strong values. However, these coastal anticyclones respond differently to the wind forcing since they remain close to the coast, in shallow-waters, unlike the M_IE15 which propagates offshore in deep water. The impact of the bottom friction or the coastal dissipation seems to limit the wind amplification of these coastal anticyclones.

Modeling Progressive Settlement of a Railway Bridge Transition

2016 ◽  
Author(s):  
Stephen T. Wilk ◽  
Timothy D. Stark
Keyword(s):  
Numerical Model ◽  
Three Dimensional ◽  
Surface Profile ◽  
Railway Bridge ◽  
Wheel Load ◽  
Bridge Abutment ◽  
The Impact

This paper illustrates the impact of progressive settlement on a railway bridge transition using a three-dimensional dynamic numerical model that includes the train truck, rails, ties, ballast, subgrade, and bridge abutment and structure. A settlement law that relates tie load to ballast settlement is presented and demonstrated using an iterative fashion to evaluate bridge transition response to 28 MGT. The results illustrate: (1) development of the commonly observed dip about 2.5 to 3.7 m (8 to 12 feet) from the entrance bridge abutment, (2) tie-ballast gaps progressively increase in height and expand to ties outwards from the bridge abutment, (3) a redistribution of load to ties outwards from the bridge abutment as tie-ballast gaps develop and increase, and (4) a ballast surface profile that attempts to minimize tie loads by evenly distributing the wheel load amongst adjacent ties.

A three-dimensional groundwater flow simulation of Granger Basin, Yukon, Canada

2021 ◽  
Author(s):  
Audrey Woo ◽  
Jeffrey McKenzie ◽  
Sean Carey
Keyword(s):  
Climate Change ◽  
Numerical Model ◽  
Groundwater Flow ◽  
Average Rate ◽  
Three Dimensional ◽  
The Arctic ◽  
Future Research ◽  
Surface Boundary ◽  
Discontinuous Permafrost ◽  
The Impact

<p>Groundwater flow and exfiltration (discharge) in Arctic and Subarctic mountain regimes is poorly understood yet plays an important role in areas underlain by continuous and discontinuous permafrost. Permafrost, ground with a perennial temperature below 0°C, acts as an impermeable barrier to groundwater flow and influences hydrogeologic connectivity and storage. The Arctic is warming at twice the global average rate, leading to rapid permafrost thaw with unclear consequences for groundwater systems. In this study, we develop a numerical groundwater model of the Granger Basin, Yukon, to further our understanding of the influence of permafrost and thaw on groundwater flow in basins impacted by climate change.</p><p>Granger Basin is a 7.6 km<sup>2</sup>  headwater catchment located within the Wolf Creek Research Basin, Yukon, Canada. It is representative of a subarctic-continental mountain environment with already observable climate change impacts. To date, there has been limited hydrogeology monitoring or numerical modeling at this site. To investigate cryohydrogeologic processes within the basin, we integrate existing field data, including 30 years of hydrometeorological records and geophysical data into a three-dimensional numerical model with saturated-unsaturated groundwater flow. We use the SUTRA-ice numerical model that couples groundwater flow and energy transport with dynamic freeze-thaw processes. The model incorporates both time-dependent thermal and hydrological surface boundary conditions and is used parametrically to understand the generation of groundwater baseflow in this setting. We will present initial results that will evaluate the impact of different hydrogeologic properties on the generation of groundwater streamflow in Wolf Creek, how permafrost in transition affects the groundwater system, and provide the framework for future research directions.</p>

Analyzing the Impact of X-Ray Tomography on the Reliability of Integrated Circuits

2015 ◽  
Author(s):  
Halit Dogan ◽  
Md Mahbub Alam ◽  
Navid Asadizanjani ◽  
Sina Shahbazmohamadi ◽  
Domenic Forte ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
3D Imaging ◽  
Three Dimensional ◽  
Serial Sectioning ◽  
Promising Technique ◽  
Flash Memories ◽  
X Ray ◽  
3D Information ◽  
The Impact

Abstract X-ray tomography is a promising technique that can provide micron level, internal structure, and three dimensional (3D) information of an integrated circuit (IC) component without the need for serial sectioning or decapsulation. This is especially useful for counterfeit IC detection as demonstrated by recent work. Although the components remain physically intact during tomography, the effect of radiation on the electrical functionality is not yet fully investigated. In this paper we analyze the impact of X-ray tomography on the reliability of ICs with different fabrication technologies. We perform a 3D imaging using an advanced X-ray machine on Intel flash memories, Macronix flash memories, Xilinx Spartan 3 and Spartan 6 FPGAs. Electrical functionalities are then tested in a systematic procedure after each round of tomography to estimate the impact of X-ray on Flash erase time, read margin, and program operation, and the frequencies of ring oscillators in the FPGAs. A major finding is that erase times for flash memories of older technology are significantly degraded when exposed to tomography, eventually resulting in failure. However, the flash and Xilinx FPGAs of newer technologies seem less sensitive to tomography, as only minor degradations are observed. Further, we did not identify permanent failures for any chips in the time needed to perform tomography for counterfeit detection (approximately 2 hours).

A THREE-DIMENSIONAL NUMERICAL MODEL FOR SELECTIVE WITHDRAWAL IN COASTAL AREA

2018 ◽  
Vol 74 (5) ◽  
pp. I_571-I_576
Author(s):  
Yasuo NIIDA ◽  
Norikazu NAKASHIKI ◽  
Takaki TSUBONO ◽  
Shin’ichi SAKAI ◽  
Teruhisa OKADA
Keyword(s):  
Numerical Model ◽  
Coastal Area ◽  
Three Dimensional ◽  
Selective Withdrawal

scholarly journals Blowing and drifting snow in Alpine terrain: numerical simulation and related field measurements

1998 ◽  
Vol 26 ◽  
pp. 174-178 ◽  
Author(s):  
Peter Gauer
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Three Dimensional ◽  
Field Measurements ◽  
Blowing Snow ◽  
Related Field ◽  
Drifting Snow ◽  
Physically Based ◽  
Snow Transport

A physically based numerical model of drifting and blowing snow in three-dimensional terrain is developed. The model includes snow transport by saltation and suspension. As an example, a numerical simulation for an Alpine ridge is presented and compared with field measurements.

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