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Single-phase mixing through a narrow gap
Mixing through narrow gaps connecting adjacent flow paths is an important mass and heat transfer process for many thermo-hydraulic applications. Such flows are considered balanced when the inlet flow speeds of adjacent subchannels are matched. In the present work, experimental observations are presented for balanced and unbalanced flows including the mixing coefficients and flow visualization within the gap. The large coherent structures are identified, with frequency in general agreement with those reported by previous investigators. To utilize Proper Orthogonal Decomposition (POD) for the discrete data yielded by PIV, we employ method of Singular Value Decomposition (SVD). The bulk of the mixing is attributed to the dominant modes and demonstrate that mixing rates estimated from velocity measurements are in fair agreement with mixing coefficients based on tracer concentration measurements
Logic-controlled solid state switchgear for 270 volts dc
A feasibility study to design and demonstrate solid state switchgear in the form of circuit breakers and a power transfer switch is described. The switchgear operates on a nominal 270 V dc circuit and controls power to a load of up to 15 amperes. One circuit breaker may be interconnected to a second breaker to form a power transfer switch. On-off and transfer functions of the breakers or the transfer switch are remotely controlled. A number of reclosures with variable time delay between tripout and reclosure are programmed and controlled by integrated analog and COSMOS logic circuits. A unique commutation circuit, that generates only minimal transient disturbance to either source or load, was developed to interrupt current flow through the main SCR switching element. Laboratory tests demonstrated performance of the solid state circuit breakers over specified voltage and temperature ranges
Impactite and pseudotachylite from Roter Kamm Crater, Namibia
Pseudotachylite is known to occur in a variety of geologic settings including thrust belts (e.g., the Alps and the Himalayas) and impact craters such as Roter Kamm, Namibia. Controversy exists, however, as to whether pseudotachylite can be produced by shock brecciation as well as by tectonic frictional melting. Also open to debate is the question of whether pseudotachylites form by frictional fusion or by cataclasis. It was speculated that the pseudotachylite at Roter Kamm was formed by extensional settling and adjustment of basement blocks during 'late modification stage' of impact. The occurrence of pseudotachylite in association with rocks resembling quenched glass bombs and melt breccias in a relatively young crater of known impact origin offers a rare opportunity to compare features of these materials. Petrographic, x-ray diffraction, and electron microprobe analyses of the impactites and pseudotachylites are being employed to determine the modes of deformation and to assess the role of frictional melting and comminution of adjacent target rocks
Carbon-On-Carbon Manufacturing
The presently disclosed technology relates to carbon-on-carbon (C/C) manufacturing techniques and the resulting C/C products. One aspect of the manufacturing techniques disclosed herein utilizes two distinct curing operations that occur at different times and/or using different temperatures. The resulting C/C products are substantially non-porous, even though the curing operation(s) substantially gasify a liquid carbon-entrained filler material that saturates a carbon fabric that makes up the C/C products
Bankruptcy--Section 70c--Recent Reactions To \u3cem\u3eConstance v. Harvey\u3c/em\u3e
Renewed interest in section 70c has developed recently, primarily because of several significant decisions in the federal courts. It is the purpose of this comment to consider the impact of these developments on the power of the trustee to avoid otherwise valid security devices
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