Krylov eigensolvers are used in many scientific fields, such as nuclear physics, page ranking, oil and gas exploration, etc... In this paper, we focus on the ERAM Krylov eigensolver whose convergence is strongly correlated to the Krylov subspace size and the restarting vector v0, a unit norm vector. We focus on computing the restarting vector v0 to accelerate the ERAM convergence. First, we stu...

The use of microfluidic devices to control drops of water in a carrier oil is a promising means of performing biological and chemical assays. An essential requirement for this is the controlled coalescence of pairs of drops to mix reagents together. We show that this can be accomplished through electrocoalescence of drops synchronized by size-dependent flow in microfluidic channels. Smaller dro...

*Correspondence: Olav Aursjø and Knut J. Måløy, Department of Physics, University of Oslo, PO Box 1048 Blindern, NO-0316 Oslo, Norway e-mail: [email protected]; [email protected] We present an experimental study of two-phase flow in a quasi-two-dimensional porous medium. The two phases, a water-glycerol solution and a commercial food grade rapeseed/canola oil, having an oil to water-gly...

One region of the electromagnetic spectrum that is relatively unexploited for materials characterization is the millimeter wave band frequencies roughly between 40 and 300 GHz . Millimeter wave techniques involve free-space noncontacting measurements which have a length scale that makes them ideal for characterizing bulk properties of multicomponent composites where the scale of homogeneity is ...

The concept of brittleness plays a crucial role in the development of tight oil and gas as it reflects a rock’s ability to fail and maintain a fracture in a hydraulic fracture experiment. Conventional methods that attempt to quantify the degree of brittleness associated with a rock mass have a few shortcomings. For example, failure criteria are not used and only the effective moduli are conside...

A convective flow system is engendered when two liquid droplets, or a liquid droplet and a solid surface, are maintained at different temperatures. Such flows give rise to Marangoni forces which under proper conditions prevent droplet coalescence, cause fluid motion, and dewetting. We present a study of adsorbed and applied fluid movement on a solid surface driven by surface tension gradients c...

A recent analogy between stripe domain structures of uniaxial magnetic garnet films and smectic liquid crystals is extended, using general energetic and symmetry considerations. The analogy is furthermore strengthened by remarking that the growth of magnetized stripes in a magnetic film is similar to the swelling of lyotropic smectic liquid crystals occurring under changes of water or oil conce...

We report an infrared (IR) optical switch using a position-shifting glycerol droplet. The droplet is surrounded by density-matched oil. In the voltage-on state, the droplet shifts in one direction. Upon removing the voltage, the droplet returns to its original position with the aid of interfacial tensions. Due to the strong absorption of glycerol at 1.55 lm, our IR optical switch shows 95:1 con...

The development of methods for mobilizing residual organic liquids trapped in porous media is becoming increasingly important as world demand for oil increases and because of the need to remediate aquifers degraded by slow-dissolving organic contaminants. Low-frequency elastic wave stimulation is one such technique, but until recently the lack of a mechanistic understanding of the effects of vi...

I present an idealized physical model of steamflood fluid-flow and make rock physics predictions of seismic impedance changes that might be observable in 3-D surface seismic monitoring data. Four distinct fluid-flow phases are considered. Closest to the steam injection well, a small hot steam zone should be very visible in seismic data due to a predicted 30% decrease in P-wave velocity (Vp) com...