A slab-on-slab model for the Flims rockslide (Swiss Alps)

2005 ◽  
Vol 42 (2) ◽  
pp. 587-600 ◽  
Author(s):  
Nicolas Pollet ◽  
Roger Cojean ◽  
Réjean Couture ◽  
Jean-Luc Schneider ◽  
Alexander L Strom ◽  
...  
Keyword(s):  
Rock Mass ◽  
High Speed ◽  
Fine Particles ◽  
Rock Avalanche ◽  
Swiss Alps ◽  
Topographic Effects ◽  
Rhine River ◽  
Slab Model ◽  
Original Rock ◽  
The Right

The Flims rockslide is the largest landslide in the Alps, with an estimated volume of 12 km3. It resulted from a prehistoric high-speed movement of a large limestone mass. Several main factors influenced the mobility of the Flims rockslide: (i) the steep slopes of the Rhine River valley that blocked the spreading of the rock debris out of the limits of Rabiusa and Carreratobel tributary valleys; (ii) the resisting forces taking place at the base of the rockslide by friction and substratum obstacles; and (iii) the rock mass evolving to a granular state, as observed in the deposits, in which coherence of the original rock massif has been preserved. We expect that most of the energy was consumed by impacting on the opposite slope, forcing the rock mass to stop. Lateral parts and some portions of debris, which entered valleys of the right tributaries of the Rhine River, created tongues by rock avalanche motion, indicating transport velocity. These rock masses eroded the valley fill to create a large mixed mass at the toe of the rockslide deposits. Thus, the Flims rock slope movement can be classified as a rockslide to its middle section and as rock avalanches at its lateral margins. A slab-on-slab model is proposed to characterize transformation of the rock mass during transport, with different stages of motion. Beginning as a rockslide, a delaminating process took place to produce a multislab shearing motion. Shearing and fracturing create dilatancy of the sliding rock debris, with spreading constrained by topographic effects. Dynamic disintegration processes explain the production of fine particles and are at the origin of the granular state of the deposits. Lateral sections of the debris mass continued to flow in the absence of topographic constraints.Key words: rockslide, rock avalanche, Flims, disintegration, topographic control.

Artificial Latices

1944 ◽  
Vol 17 (2) ◽  
pp. 533-540
Author(s):  
E. W. Madge
Keyword(s):  
High Speed ◽  
Fine Particles ◽  
Aqueous Dispersion ◽  
The Other ◽  
Aqueous Dispersions ◽  
Heavy Machinery ◽  
Plastic Substance ◽  
The Right ◽  
High Shearing ◽  
Dispersing Agents

Abstract An artificial latex is usually understood to mean one prepared by the inversion of the solid plastic, and the main purpose of this paper is to consider latices of this type, although towards the end some attention is given to the synthetic latices. Given the right conditions of dispersion and the correct dispersing agents, satisfactory aqueous dispersions may be prepared from almost any plastic substance. In dispersion processes generally the material to be dispersed may occur as a liquid, as a solid, or as a plastic which is physically intermediate between the two. In all such processes machinery is required capable of inducing a shear at the point of dispersion. It is a relatively simple matter to prepare an aqueous dispersion of a liquid. The technician has at his disposal several types of high-speed colloid mills in which the liquid is subjected to high shearing forces in the presence of suitable colloids. For solids in hard homogeneous massive form, not merely present as aggregates of otherwise fine particles, grinding machinery is necessary. For the intermediate plastics, relatively heavy machinery capable of inducing shearing forces in the material itself is required. Consequently, if the plastic substance can be rendered fluid by solution in a suitable solvent, it can be dispersed by passage through some form of standard colloid mill. On the other hand, if it can be rendered friable by loading with large proportions of powder, it may be dispersed with the aid of some form of grinding machinery. Both methods were practised by the earlier investigators, and in both eases dispersions were obtained in which an undesirable ingredient was present in large quantities. The solvent could, of course, be distilled off, but its use and recovery was an unnecessary expense and the final dispersion was not always controllable as regards stability.

Influence of social media marketing towards purchase of residential property

2019 ◽  
Vol 118 (6) ◽  
pp. 145-149
Author(s):  
A. Ekanthalingam ◽  
Dr. A. Gopinath
Keyword(s):  
Social Media ◽  
High Speed ◽  
Word Of Mouth ◽  
Marketing Strategies ◽  
Social Media Marketing ◽  
Purchase Decision ◽  
Residential Property ◽  
Customer Delight ◽  
The Right ◽  
Potential Customers

‘Marketing’ is not just an activity. It is a process, a philosophy and a phenomenon. The evolution of marketing has produced tremendous benefits to business and end consumers. The innovation in this field has been steady and yet at high speed. From ‘word of mouth advertising’ which was the only option earlier we are now at the mercy of what consumers are sharing about their experience on the internet. Social Media has become more powerful than what we think and this article shows how we can leverage this to benefit the top-line and customer delight. We dive deep to understand the influence Social Media can create towards purchase of residential property. As much complex it is to make the purchase decision of a property, it is equally difficult for marketers to send the right message to their target audience. Through this article, we are trying to see how marketers have transformed their traditional marketing strategies to address the needs of the millennial population, who are the most potential customers for property purchase.

scholarly journals Slope Failure in a Period of Increased Landslide Activity: Sennwald Rock Avalanche, Switzerland

Geosciences ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 331
Author(s):  
Selçuk Aksay ◽  
Susan Ivy-Ochs ◽  
Kristina Hippe ◽  
Lorenz Grämiger ◽  
Christof Vockenhuber
Keyword(s):  
Slope Failure ◽  
Rock Avalanche ◽  
Eastern Alps ◽  
Rock Failure ◽  
Rhine River ◽  
Stratigraphic Sequence ◽  
Exposure Age ◽  
Wet Climate ◽  
Cosmogenic Nuclide Dating ◽  
Additional Support

The Säntis nappe is a complex fold-and-thrust structure in eastern Switzerland, consisting of numerous tectonic discontinuities and a range of hillslopes prone to landsliding and large slope failures that modify the topography irreversibly. A slope failure, namely the Sennwald rock avalanche, occurred in the southeast wall of this fold-and-thrust structure due to the rock failure of Lower Cretaceous Helvetic limestones along the Rhine River valley. In this research, this palaeolandslide is examined in a multidisciplinary approach for the first time with detection and mapping of avalanche deposits, dynamic run-out modelling and cosmogenic nuclide dating. During the rock failure, the avalanche deposits were transported down the hillslope in a spreading-deck fashion, roughly preserving the original stratigraphic sequence. The distribution of landslide deposits and surface exposure age of the rock failure support the hypothesis that the landslide was a single catastrophic event. The 36Cl surface exposure age of avalanche deposits indicates an age of 4.3 ± 0.5 ka. This time coincides with a notably wet climate period, noted as a conditioning factor for landslides across the Alps in the mid-Holocene. The contemporaneity of our event at its location in the Eastern Alps provide additional support for the contention of increased regional seismic activity in mid-Holocene.

Hard Nano-Crystalline Coatings for Cutting Tools

2007 ◽  
Vol 567-568 ◽  
pp. 185-188 ◽  
Author(s):  
Miroslav Piska
Keyword(s):  
High Speed ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Dry Cutting ◽  
Nano Crystalline ◽  
The Right ◽  
Machining Productivity ◽  
Hard Cutting ◽  
Cutting Tool Materials

Modern trends in metal cutting, high speed/feed machining, dry cutting and hard cutting set more demanding characteristics for cutting tool materials. The exposed parts of the cutting edges must be protected against the severe loading conditions and wear. The most significant coatings methods for cutting tools are PVD and CVD/MTCVD today. The choice of the right substrate or the right protective coating in the specific machining operation can have serious impact on machining productivity and economy. In many cases the deposition of the cutting tool with a hard coating increases considerably its cutting performance and tool life. The coating protects the tool against abrasion, adhesion, diffusion, formation of comb cracks and other wear phenomena.

scholarly journals The Behavior of Jet Currents over a Continental Slope Topography with a Possible Application to the Northern Current

2005 ◽  
Vol 35 (5) ◽  
pp. 790-810 ◽  
Author(s):  
M. M. Flexas ◽  
G. J. F. van Heijst ◽  
R. R. Trieling
Keyword(s):  
High Speed ◽  
Bottom Topography ◽  
Laboratory Model ◽  
Topographic Effects ◽  
Topographic Slope ◽  
Eddy Formation ◽  
Slow Flows ◽  
Bottom Depth ◽  
Source Sink ◽  
Northern Current

Abstract The Northern Current is a slope current in the northwest Mediterranean that shows high mesoscale variability, generally associated with meander and eddy formation. A barotropic laboratory model of this current is used here to study the role of the bottom topography on the current variability. For this purpose, a source–sink setup in a cylindrical tank placed on a rotating table is used to generate an axisymmetric barotropic current. To study inviscid topographic effects, experiments are performed over a topographic slope and also over a constant-depth setup, the latter being used as a reference for the former. With the aim of obtaining a fully comprehensive view of the vorticity balance at play, the flow may be forced in either azimuthal direction, leading to a “westward” prograde current (similar to the Northern Current) or an “eastward” retrograde current. For slow flows, eastward and westward currents showed similar patterns, dominated by Kelvin–Helmholtz-type instabilities. For high-speed flows, eastward and westward currents showed very different behavior. In eastward currents, the variability is observed to concentrate toward the center of the jet and shows strong meandering formation. Westward currents, instead, showed major variability toward the edges of the jet, together with a strong variability over the uppermost slope, which has been associated here with a topographic Rossby wave trapped over the shelf break. The differences between eastward and westward jets are explained through the balance between shear-induced and topographically induced vorticity at play in each case. Moreover, a model of jets over a beta plane is successfully applied here, allowing its extension to any ambient potential vorticity gradient caused either by latitudinal or bottom depth changes.

scholarly journals Numerical and Experimental Investigation on Key Parameters of the Respimat® Spray Inhaler

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 44
Author(s):  
Yi Ge ◽  
Zhenbo Tong ◽  
Renjie Li ◽  
Fen Huang ◽  
Jiaqi Yu
Keyword(s):  
High Speed ◽  
Fine Particles ◽  
Geometric Parameters ◽  
Metered Dose Inhalers ◽  
Geometric Pattern ◽  
Long Duration ◽  
Metered Dose ◽  
New Type ◽  
Computational Fluid Dynamics Cfd ◽  
Spray Velocity

Respimat®Soft MistTM is a newly developed spray inhaler. Different from traditional nebulizers, metered-dose inhalers, and dry powder inhalers, this new type of inhaler can produce aerosols with long duration, relatively slow speed, and a high content of fine particles. Investigating the effect of the key geometric parameters of the device on the atomization is of great significance for generic product development and inhaler optimization. In this paper, a laser high-speed camera experimental platform is built, and important parameters such as the geometric pattern and particle size distribution of the Respimat®Soft MistTM are measured. Computational fluid dynamics (CFD) and the volume of fluid method coupled with the Shear Stress Transport (SST) k-ω turbulence model are applied to simulate the key geometric parameters of the device. The effects of geometric parameters on the spray velocity distribution and geometric pattern are obtained. The angle of flow collision, the sphere size of the central divider and the length and width of the flow channel show significant impacts on the spray atomization.

Simulation of Multi-Stage Compressor at Off-Design Conditions

2017 ◽  
Author(s):  
Feng Wang ◽  
Mauro Carnevale ◽  
Luca di Mare ◽  
Simon Gallimore
Keyword(s):  
Mass Flow ◽  
High Speed ◽  
Eddy Viscosity ◽  
Turbulence Models ◽  
Viscosity Model ◽  
Eddy Viscosity Model ◽  
Multi Stage ◽  
Pressure Profiles ◽  
Non Linear ◽  
The Right

Computational Fluid Dynamics (CFD) has been widely used for compressor design, yet the prediction of performance and stage matching for multi-stage, high-speed machines remain challenging. This paper presents the authors’ effort to improve the reliability of CFD in multistage compressor simulations. The endwall features (e.g. blade fillet and shape of the platform edge) are meshed with minimal approximations. Turbulence models with linear and non-linear eddy viscosity models are assessed. The non-linear eddy viscosity model predicts a higher production of turbulent kinetic energy in the passages, especially close to the endwall region. This results in a more accurate prediction of the choked mass flow and the shape of total pressure profiles close to the hub. The non-linear viscosity model generally shows an improvement on its linear counterparts based on the comparisons with the rig data. For geometrical details, truncated fillet leads to thicker boundary layer on the fillet and reduced mass flow and efficiency. Shroud cavities are found to be essential to predict the right blockage and the flow details close to the hub. At the part speed the computations without the shroud cavities fail to predict the major flow features in the passage and this leads to inaccurate predictions of massflow and shapes of the compressor characteristic. The paper demonstrates that an accurate representation of the endwall geometry and an effective turbulence model, together with a good quality and sufficiently refined grid result in a credible prediction of compressor matching and performance with steady state mixing planes.

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