Extra, Guus, Ed.; Verhoeven, Ludo, Ed.
Papers from a 1990 Dutch colloquium on immigrant language varieties in Europe are presented in four categories: (1) use of immigrant language varieties in Europe; (2) first language acquisition in a second language context; (3) code-switching; and (4) language maintenance and loss. Papers include: "Sweden Finnish" (Jarmo Lainio);…
Sousa, F.S.; Portela, L.M.; Mudde, R.F.; Mangiavacchi, N.
We present a method for fully-resolved simulations of bubbly flows using a front-tracking/front-capturing technique. The method is a modification of a marker-and-cell method developed previously for free-surface flows. The basic approach is somehow similar to the front-tracking method of Tryggvason:
Rev. Fluid Mech. 22, 473-537  Huerre P. 2000. Open shear flow instabilities. In Perspectives in Fluid Dynamics , ed. G.K. Batchelor , H.K... fluid dynamics aspect from the reactive flow processes, and studying the coupling of non-reactive injector flow instabilities with external pressure...2] Dahm, W. J. A., Frieler, C.E., and Tryggvason, G. 1992 Vortex structure and dynamics in the near field of a coaxial jet. J. Fluid Mech. 241
pSUMMER- 1983 STAFF SeFlieri, Glenn Massachusetts Institute of Technology Howard , Louis Florida State University Malkus, Willem Massachusetts Institute of...Stern, Killworth, Malkus Front Row: Spiegel, Aref, Samelson, Veronis, Mellor, Howard , Jones, Tryggvason, Mory, Nilno, Flament, Corfield Inset: Voropaev...combining the formulae of Ruddick and Turner (1979) and Toole and Georgi (1981) on the thickness and growth rate of the double diffusive intrusions that
Morozova et al., 1999; Tryggvason et al., 2001). The West Siberian Basin (Figure 1-1) is the largest known basin structure in the world and covers over 3.4...mostly between 395 and 1212 m, and the source media include salt, sandstone/shale, clay, limestone/dolomite, granite, gabbro , tuff, apatite, anhydrite...shots in granite, 2 in tuff, 2 in chalk, 1 in gabbro , and 1 in anhydrite. Seven PNE profiles (RUBY-l, RUBY-2, QUARTZ, CIIATON, KIMBERLITE, RIFT, and
a grant from the Steven and Michelle Kirsch Foundation to continue working on the mechanisms underlying epithelial reprogramming of skin. 3. In...Sciences PUBLICATIONS 1. Boyd, C.D., Weliky, K., Toth-Fejel, S-E., Deak, S.B., Christiano, A.M., Mackenzie, J.W. Sandell , L.J., Tryggvason, K. and Magenis, E...Epidermolysis Bullosa: Absence of a Nonsense Mutation in the a3 Chain Gene of Laminin 5 (LAMA3). Genomics 29:282-284. 43. Olson, T.M., Michels , V.V., Urban, Z
Fluid Mech. 22, 473-537 24Huerre P. 2000. Open shear flow instabilities. In Perspectives in Fluid Dynamics , ed. G.K. Batchelor , H.K. Moffatt, M.G...Tryggvason, G. 1992 Vortex structure and dynamics in the near field of a coaxial jet. J. Fluid Mech. 241, 371-402. 3Wicker, R.B. and Eaton, J.K. 1994 Near...20Arienti, M, and Soteriou, M.C. 2009 Time-resolved proper orthogonal decomposition of liquid jet dynamics . Phys. Fluids 21, 112104. 21Narayanan,V
This volume of the Shock Wave Science and Technology Reference Library is concerned with the interplay between bubble dynamics and shock waves. It is divided into four parts containing twelve chapters written by eminent scientists. Topics discussed include shock wave emission by laser generated bubbles (W Lauterborn, A Vogel), pulsating bubbles near boundaries (DM Leppinen, QX Wang, JR Blake), interaction of shock waves with bubble clouds (CD Ohl, SW Ohl), shock propagation in polydispersed bubbly liquids by model equations (K Ando, T Colonius, CE Brennen. T Yano, T Kanagawa, M Watanabe, S Fujikawa) and by DNS (G Tryggvason, S Dabiri), shocks in cavitating flows (NA Adams, SJ Schmidt, CF Delale, GH Schnerr, S Pasinlioglu) together with applications involving encapsulated bubble dynamics in imaging (AA Doinikov, A Novell, JM Escoffre, A Bouakaz), shock wave lithotripsy (P Zhong), sterilization of ships’ ballast water (A Abe, H Mimura) and bubbly flow model of volcano eruptions ((VK Kedrinskii, K Takayama...
Acta Astronautica, Vol. 48 (2001), contains in pp. 59-70 an article discussing the benefits of conducting liquid metal diffusion experiments in space using the Canadian Microgravity Vibration Isolation Mount (MIM) [B.V. Tryggvason, R.F. Redden, R.A. Herring, W.M.B. Duval, R.W. Smith, K.S. Rezkallah, S.Varma, The vibration environment on the International Space Station: its significance to fluid-based experiments, Acta Astronautica 48 (2001) 59-70]. Two main problems have been identified with this published article: (1) On the basis of experimental results, the authors claim that the diffusion coefficients of gold in lead measured on the ground are much higher than those obtained under microgravity conditions. Close examination of the problems encountered during processing of the capillary diffusion couples on the MIR space station reveals that this claim cannot be justified. (2) The authors further conclude that there is a linear relationship between diffusion coefficient (D) and temperature (T) when g-jitter is suppressed. This conclusion is questionable because the methodology used to determine the processing time and temperatures on the MIR space station does not seem to be scientific.
Lakehal, D.; Métrailler, D.; Reboux, S.
This paper presents Direct Numerical Simulation (DNS) results of a turbulent water flow in a channel at Reτ = 400 laden with 0.25 mm diameter air bubbles clustered near the wall (maximum void fraction of α = 8% at y+ ˜ 20). The bubbles were fully resolved using the level set approach built within the CFD/CMFD code TransAT. The fluid properties (air and water) were kept real, including density, viscosity, and surface tension coefficient. The aim of this work is to understand the effects of the bubbles on near-wall turbulence, paving the way towards convective wall-boiling flow studies. The interactions between the gas bubbles and the water stream were studied through an in-depth analysis of the turbulence statistics. The near-wall flow is overall affected by the bubbles, which act like roughness elements during the early phase, prior to their departure from the wall. The average profiles are clearly altered by the bubbles dynamics near the wall, which somewhat contrasts with the findings from similar studies [J. Lu and G. Tryggvason, "Dynamics of nearly spherical bubbles in a turbulent channel upflow," J. Fluid Mech. 732, 166 (2013)], most probably because the bubbles were introduced uniformly in the flow and not concentrated at the wall. The shape of the bubbles measured as the apparent to initial diameter ratio is found to change by a factor of at least two, in particular at the later stages when the bubbles burst out from the boundary layer. The clustering of the bubbles seems to be primarily localized in the zone populated by high-speed streaks and independent of their size. More importantly, the bubbly flow seems to differ from the single-phase flow in terms of turbulent stress distribution and energy exchange, in which all the stress components seem to be increased in the region very close to the wall, by up to 40%. The decay in the energy spectra near the wall was found to be significantly slower for the bubbly flow than for a single-phase flow, which
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Lund, Björn; Berglund, Karin; Tryggvason, Ari; Dineva, Savka; Jonsson, Linda
Induced seismic events in a mining environment are a potential hazard, but they can be used to gain information about the rock mass in the mine which otherwise would be very difficult to obtain. In this study we use approximately 1.2 million mining induced seismic events in the Kiirunavaara iron ore mine in northernmost Sweden to image the rock mass using local event travel-time tomography. In addition, relocation of the events significantly improves the possibility to infer structural information and rock damage. The Kiirunavaara mine is one of the largest underground iron ore mines in the world. The ore body is a magnetite sheet of 4 km length, with an average thickness of 80 m, which dips approximately 55° to the east. Mining production is now at a depth of 785 - 855 m. During 2015 the seismic system in the mine recorded on average approximately 1,000 local seismic events per day. The events are of various origins such as shear slip on fractures, non-shear events and blasts, with magnitudes of up to 2.5. We use manually picked P- and S-waves in the tomography and we require that both phases are present as we found that events from the routine processing need screening for anomalous P- versus S-travel times, indicating occasional erroneous phase associations. For the tomography we use the 3D local earthquake tomography code PStomo_eq (Tryggvason et al., 2002), which we adjusted to the mining scale. The study volume is 1.2 x 1.8 x 1.8 km and the velocity model grid size is 10x10x10 meter. The tomographic images show clearly defined regions of high and low velocities. Low velocity zones are associated with mapped clay zones and areas of mined out ore, and also with the near-ore tunnel infrastructure in the foot-wall. We also see how the low S-velocity anomaly continues to depth below the current mining levels, following the inferred direction of the ore. The tomography shows higher P- and S-velocities in the foot-wall away from the areas of mine infrastructure. We