54,549 research outputs found
Acoustic wave analysis
The primary mechanism for generation of acoustic waves in a centrifugal pump, due to the rotor/stator interaction, is an unsteady source at the entrance of the blade row as represented by the unsteady velocity field. The amplitudes of wave generated by pressure loading on the blades and by velocity boundary condition are compared
Method of calculating blade-to-blade plane flow in centrifugal pump
Steam filament solution determines velocity distribution due to potential flow in the blade-to-blade plane of the radial impeller. This is used to determine the mass-averaged relative fluid angle, which is in turn used in an axisymmetric program to obtain steam surfaces of the assumed axisymmetric flow
Summary, study of pump discharge pressure oscillations
Analytical data on pump-generated pressure, flow, blade wake, cavitation, and stall oscillations for application to turbopump desig
Channel-wall limitations in the magnetohydrodynamic induction generator
Discussion of magnetohydrodynamic induction generator examines the machine in detail and materials problems influencing its design. The higher upper-temperature limit of the MHD system promises to be more efficient than present turbine systems for generating electricity
Criticism of "Necessity of simultaneous co-existence of instantaneous and retarded interactions in classical electrodynamics" by Andrew E. Chubykalo and Stoyan J. Vlaev
The demonstration that the electromagnetic fields derived from the
Lienard-Wiechert potentials do not satisfy the Maxwell equations is proved to
be false. Errors were made in the computation of the derivatives of retarded
quantities. The subsequent inference of the necessity of both instantaneous and
retarded electromagnetic interactions cannot be made. Different choices of
gauge can lead to a variety of forms for the scalar and vector potentials,
always with the same retarded fields. Classical electromagnetic theory is
complete as usually expressed. One may choose to work in the Lorenz gauge in
which all quantities are retarded.Comment: pdf file, 5 pages, submitted to Int. J. Mod. Phy
Thermionic research and development program Final report
Rhenium electrode material investigation and performance studies of low temperature cesium vapor thermionic converter
Comment: Citation Statistics
We discuss the paper "Citation Statistics" by the Joint Committee on
Quantitative Assessment of Research [arXiv:0910.3529]. In particular, we focus
on a necessary feature of "good" measures for ranking scientific authors: that
good measures must able to accurately distinguish between authors.Comment: Published in at http://dx.doi.org/10.1214/09-STS285B the Statistical
Science (http://www.imstat.org/sts/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Ultrasmall volume Plasmons - yet with complete retardation effects
Nano particle-plasmons are attributed to quasi-static oscillation with no
wave propagation due to their subwavelength size. However, when located within
a band-gap medium (even in air if the particle is small enough), the particle
interfaces are acting as wave-mirrors, incurring small negative retardation.
The latter when compensated by a respective (short) propagation within the
particle substantiates a full-fledged resonator based on constructive
interference. This unusual wave interference in the deep subwavelength regime
(modal-volume<0.001lambda^3) significantly enhances the Q-factor, e.g. 50
compared to the quasi-static limit of 5.5.Comment: 16 pages, 6 figure
Dead cone due to parton virtuality
A general expression for the dead cone of gluons radiated by virtual partons
has been derived. The conventional dead cone for massive on-shell quarks and
the dead cone for the massless virtual partons have been obtained by using
different limits of the general expression. Radiative suppression due to the
virtuality of initial parton jets in Heavy-Ion Collisions (HIC) has been
discussed. It is observed that the suppression caused by the high virtuality is
overwhelmingly large as compared to that on account of conventional dead-cone
of heavy quarks. The dead cone due to virtuality may play a crucial role in
explaining the observed similar suppression patterns of light and heavy quarks
jets in heavy ion collisions at Relativistic Heavy Ion Collider (RHIC)
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