![]() ![]() We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first single-phase and then multiphase flow. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. In this project, we studied all these regimes except compaction. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. These regimes are characterized by different morphology of the region invaded by the gas. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding more » large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. We have focused on the gas/brine interface at the scale of individual grains in the sediment. In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. Color codes provide an indication for the conventionality of the chord, or the particular settings chosen.= , Any change is made in real time, and is immediately audible for the user. Chords are presented as rectangular boxes, with a vertical slider and two rotary knobs for changing chord functions, substituting chords, and adding tensions, respectively. melodies, bass lines, chords, loops, rhythmic patterns, etc.). Musical adaptation (resynthesis) builds meaningful musical context from various input data (e.g. It’s simple on the outside, yet sophisticated and intelligent inside.Ī very powerful harmonic analysis atomizes even very complex multi-track songs and detects their various musical elements and their correlations. It unleashes their creativity to make better music intuitively – without restrictions. Liquid Notes is the exact opposite to this trend: we take the complexity back to music making, without any complexity for the user behind it. Numbers are hard to get in DJing, but multiple sources talk about >10 million people using DJ software today. Thanks to the large amount of technology available today, automated mixing is becoming more worrying and used by a great many. Ibiza legend Tim Sheridan recently spoke out about ‘EDM killing the art of DJing’, in particular referring to the responsibility of ‘sync buttons’ and ‘laptop DJing’ creating today’s Plastic DJs. ![]()
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