► Breakup modes of an axisymmetric, laminar compound jet of immiscible fluids in a coflowing system are numerically studied. ► A front-tracking/finite difference method is used. ► Three modes: inner ...dripping–outer dripping, inner jetting–outer jetting and mixed dripping–jetting are found. ► Transition from dripping to jetting is investigated by varying various parameters.
We present a numerical investigation of breakup modes of an axisymmetric, laminar compound jet of immiscible fluids, which flows in a coflowing immiscible outer fluid. We use a front-tracking/finite difference method to track the unsteady evolution and breakup of the compound jet, which is governed by the Navier–Stokes equations for incompressible Newtonian fluids. Numerical results show that depending on parameters such as the Reynolds number Re (in the range of 5–30) and Weber Number We (in the range of 0.1–0.7), based on the inner jet radius and inner fluid properties, the compound jet can break up into drops in various modes: inner dripping–outer dripping (dripping), inner jetting–outer jetting (jetting), and mixed dripping–jetting. Decreasing Re or increasing We promotes the jetting mode. The transition from dripping to jetting is also strongly affected by the velocity ratios, U21 (intermediate to inner velocities) and U31 (outer to inner velocities). Increasing U21 makes the inner jet thinner and stretches the outer jet and thus promotes jetting. In contrast, increasing U31 thins the outer jet, and thus, when the inner jet is dripping, the outer jet can break up into drops in the mixed dripping–jetting mode. Continuously increasing U31 results in thinning both inner and outer jets and thus produces small drops in the jetting mode. In addition, starting from dripping, a decrease in the interfacial tension ratio of the outer to inner interfaces results in the mixed dripping–jetting and jetting modes. These modes produce various types of drops: simple drops, and compound drops with a single inner drop (single-core compound drops) or a few inner drops (multi-core compound drops).
The geometrical property of an atomic structure model of the Yb-Cd icosahedral quasicrystal is discussed from the higher-dimensional viewpoint. An occupation domain for the framework that specifies ...the arrangement of the three building units of the structure is presented based on a specific archetype occupation domain for the cluster centres. Different cluster configurations are enumerated and the numerical values of their frequencies are given.
We report on the six-dimensional (6D) structural refinement of three members of the i-R-Cd quasicrystals (R= Gd, Dy, Tm) via synchrotron x-ray diffraction from single-grain samples, and show that ...this series is isostructural to the i-YbCd sub(5.7) quasicrystal. However, our refinements suggest that the R occupancy on the Yb icosahedron sites within the Tsai-type atomic cluster is approximately 80%, with the balance taken up by Cd. Similarities between the i-R-Cd series and i-ScZn sub(7.33), and their differences with i-YbCd sub(5.7) and i-Ca sub(15) Cd sub(85), indicate that there are at least two subclasses of Tsai-type icosahedral quasicrystals. We further show from x-ray resonant magnetic scattering (XRMS) measurements on a set of closely related Tb sub(1-x) Y sub(x) Cd sub(6) 1/1 approximants that the dilution of the magnetic R ions on the icosahedron within the Tsai-type cluster by nonmagnetic Y disrupts the commensurate magnetic ordering in the approximant phase.
Visualization of quasicrystal data Momma, K.; Takakura, H.
Acta crystallographica. Section A, Foundations and advances,
08/2023, Letnik:
79, Številka:
a2
Journal Article
The effects of module temperature (
T
mod) and spectral irradiance distribution on the outdoor performance of amorphous Si (a-Si) photovoltaic (PV) modules were investigated using contour maps. ...Compared to PV modules based on crystalline Si, such as single-crystalline Si (sc-Si) and multicrystalline Si, a-Si PV modules exhibit complex behavior with seasonal variation. In this study, we statistically analyzed the outdoor performance of a-Si and sc-Si PV modules. The influence of environmental factors on outdoor performance of a-Si PV modules was analyzed for two seasons, spring and autumn, in which the data periods had nearly the same average
T
mod and integrated irradiation. The outdoor performance of the a-Si PV module depends on both temperature history and light-induced degradation.
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