On the role of joint roughness on the micromechanics of rock fracturing process: a numerical study

A numerical study of the evaluation of turbulence models for predicting the thermal stratification phenomenon is presented. The tested models are the elliptic blending turbulence model (EBM), the two-layer model, the shear stress transport model (SST), and the elliptic relaxation model (V2-f). These four turbulence models are applied to the prediction of a thermal stratification in an upper plenum of a liquid metal reactor experimented at the Japan Nuclear Cooperation (JNC). The EBM and V2-f models predict properly the steep gradient of the temperature at the interface of the cold and hot regions that is observed in the experimental data, and the EBM and V2-f models have the capability of predicting the temporal oscillation of the temperature. The two-layer and SST models predict the diffusive temperature gradient at the interface of a thermal stratification and fail to predict a temporal oscillation of the temperature. In general, the EBM predicts best the thermal stratification phenomenon in the upper plenum of the liquid metal reactor.

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Theoretical analysis on electromagnetic emission of rock fracturing process

Rock Characterisation, Modelling and Engineering Design Methods ◽

10.1201/b14917-60 ◽

2013 ◽

pp. 335-338

Author(s):

P Lin ◽

X Liu ◽

S Kang ◽

C Wang

Keyword(s):

Theoretical Analysis ◽

Electromagnetic Emission ◽

Rock Fracturing ◽

Fracturing Process

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A numerical study of the windstorm Klaus: sensitivity to sea surface temperature

Annals of Geophysics ◽

10.4401/ag-6466 ◽

2014 ◽

Vol 57 (5) ◽

Author(s):

Nazario Tartaglione ◽

Rodrigo Caballero

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Numerical Study ◽

Heat Fluxes ◽

Sea Surface ◽

Moisture Convergence ◽

Convective Precipitation ◽

Limited Area ◽

Weather Forecasts

<p>This article investigates the role of sea surface temperature (SST) as well as the effects of evaporation and moisture convergence on the evolution of cyclone Klaus, which occurred on January 23 and 24, 2009. To elucidate the role of sea surface temperature (SST) and air–sea fluxes in the dynamics of the cyclone, ten hydrostatic mesoscale simulations were performed by Bologna Limited Area Model (BOLAM). The first one was a control experiment with European Centre for Medium-Range Weather Forecasts (ECMWF) SST analysis. The nine following simulations are sensitivity experiments where the SST are obtained by adding a constant value by 1 to 9 K to the ECMWF field. Results show that a warmer sea increases the surface latent heat fluxes and the moisture convergence, favoring the development of convection in the storm. Convection is affected immediately by the increased SST. Later on, drop of mean sea level pressure (MSLP) occurs together with increasing of surface winds. The cyclone trajectory is not sensitive to change in SST differently from MSLP and convective precipitation.</p>

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A Numerical Study of the Role of Wave-Wave Interactions during Sudden Stratospheric Warmings

Journal of the Atmospheric Sciences ◽

10.1175/1520-0469(1981)038<0189:ansotr>2.0.co;2 ◽

1981 ◽

Vol 38 (1) ◽

pp. 189-214 ◽

Cited By ~ 17

Author(s):

Chih-Ping F. Hsu

Keyword(s):

Numerical Study ◽

Wave Interactions

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Numerical Prediction of Rock Fracturing During the Process of Excavation

Geotechnical Applications for Earthquake Engineering ◽

10.4018/978-1-4666-0915-0.ch013 ◽

2012 ◽

pp. 225-237 ◽

Cited By ~ 1

Author(s):

Zhangtao Zhou ◽

Zheming Zhu ◽

XinXing Jin ◽

Hao Tang

Keyword(s):

Equation Of State ◽

Numerical Model ◽

Failure Criterion ◽

Material Properties ◽

Igneous Rock ◽

Surrounding Rock ◽

Rock Blasting ◽

Rock Fracturing ◽

Fracturing Process ◽

Blasting Excavation

During the process of excavation, blasting can induce cracking inside the surrounding rock. Considering the effects of material properties and loading conditions, a rock blasting excavation model with two successive excavation steps was developed through the use of AUTODYN code. Four kinds of equation of state (EOS), linear, shock, JWL, and compaction were applied to the materials employed in this numerical model. A modified principal stress failure criterion was applied to determining material statuses, and TNT explosive and a relatively homogeneous igneous rock, diorite, were used in this numerical model. By using this numerical model, rock fracturing process during blasting excavation was simulated, and rock fracturing process during two successive excavations is presented.

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