An Investigation of the Squeeze Film Between Rotating Annuli

1970 ◽  
Vol 92 (3) ◽  
pp. 435-440 ◽  
Author(s):  
C. W. Allen ◽  
A. A. McKillop
Keyword(s):  
Experimental Investigation ◽  
Melting Point ◽  
Liquid Metal ◽  
Decay Rates ◽  
Squeeze Film ◽  
Centrifugal Effect ◽  
Experimental Values ◽  
Free Falling ◽  
Air Film ◽  
Good Agreement

The squeeze film between two plane annuli is examined theoretically and experimentally. The theoretical analysis considers the inertia due to the “centrifugal effect” but neglects all other inertia terms. The experimental investigation is by means of a free-falling spinning rotor which is decelerated by the squeeze film. Fluids examined are kerosene, SAE 10 oil, and a low melting point liquid metal. Good agreement between the predicted and actual decay rates is obtained for kerosene but that for the oil and liquid metal is only fair. The theoretical and experimental values of film thickness are in good agreement. The results for the liquid metal suggest the possibility of a thin air film between the rotor and the liquid metal.

Dynamic Behavior of an Inherently Compensated Air Squeeze Film Damper

1975 ◽  
Vol 97 (4) ◽  
pp. 1399-1404 ◽  
Author(s):  
R. E. Cunningham
Keyword(s):  
Perturbation Theory ◽  
Dynamic Behavior ◽  
Squeeze Film ◽  
Pressure Perturbation ◽  
Squeeze Film Damper ◽  
Small Pressure ◽  
Excitation Frequencies ◽  
Experimental Values ◽  
Film Stiffness ◽  
Air Film

Experimental values of damping and stiffness were determined for an externally pressurized, inherently compensated, compressible squeeze-film damper up to excitation frequencies of 36,000 cycles/min. Experimental values of damping were higher than predicted by a small pressure perturbation theory at low squeeze numbers and less than predicted at high squeeze numbers. Experimental values of air film stiffness were less than the theory predicted at low squeeze numbers and much greater at higher squeeze numbers.

Characteristics of Squeeze Air Film Between Nonparallel Plates

1983 ◽  
Vol 105 (1) ◽  
pp. 147-152 ◽  
Author(s):  
H. Takada ◽  
S. Kamigaichi ◽  
H. Miura
Keyword(s):  
Pressure Transducer ◽  
Dynamic Pressure ◽  
Air Flow ◽  
Approximate Solutions ◽  
Squeeze Film ◽  
Rectangular Plates ◽  
Flow Through ◽  
Air Film ◽  
Theoretical Results ◽  
Good Agreement

The dynamic pressure in a squeeze film and the air flow through the film were analyzed experimentally and theoretically. The dynamic pressure was measured in a squeeze film between two rectangular plates with a small pressure transducer. Approximate solutions for the rectangular squeeze film were obtained analytically. The results were valid for small excursion ratios. Next, a squeeze film between nonparallel plates (wedge film) was examined. In this case, steady air flow occurred due to the unsymmetry of the pressure distribution. To investigate this fact, the air flow was measured in a spherical squeeze film. The values showed good agreement with the theoretical results.

An independent-quark model calculation for radiative decay widths of mesons in static and beyond static approximation

2010 ◽  
Vol 88 (7) ◽  
pp. 517-527 ◽  
Author(s):  
S. N. Jena ◽  
H. H. Muni ◽  
P. K. Mohapatra ◽  
P. Panda
Keyword(s):  
Radiative Decay ◽  
Photon Emission ◽  
Decay Rates ◽  
Static Approximation ◽  
Radiative Transitions ◽  
Model Predictions ◽  
Decay Widths ◽  
Experimental Values ◽  
Conventional Picture ◽  
Good Agreement

We perform a static calculation of decay widths for radiative transitions of mesons within the conventional picture of photon emission by a confined quark and (or) antiquark. As the calculation based on the moderate momentum transfer allows some amount of uncertainty to creep into the model predictions, we further apply the model for a more realistic calculation beyond the static approximation, taking into account some momentum-dependent effects due to the recoil of the daughter meson. The results obtained for the decay widths of radiative transitions of light mesons are improved and are in good agreement with the experimental values. The predictions on the decay rates of heavy mesons are also affected and are comparable with those of other model predictions.

Experimental investigation and modelling of light scattering in a-Si:H solar cells deposited on glass/ZnO:Al substrates

2002 ◽  
Vol 715 ◽  
Author(s):  
J. Krc ◽  
M. Zeman ◽  
O. Kluth ◽  
F. Smole ◽  
M. Topic
Keyword(s):  
Surface Roughness ◽  
Experimental Investigation ◽  
Solar Cells ◽  
Angular Distribution ◽  
Light Scattering ◽  
Optical Model ◽  
Distribution Functions ◽  
Interface Roughness ◽  
Scattering Parameters ◽  
Good Agreement

AbstractThe descriptive scattering parameters, haze and angular distribution functions of textured ZnO:Al transparent conductive oxides with different surface roughness are measured. An approach to determine the scattering parameters of all internal interfaces in p-i-n a-Si:H solar cells deposited on the glass/ZnO:Al substrates is presented. Using the determined scattering parameters as the input parameters of the optical model, a good agreement between the measured and simulated quantum efficiencies of the p-i-n a-Si:H solar cells with different interface roughness is achieved.

CERROTRU Alloy

Alloy Digest ◽  
1979 ◽  
Vol 28 (12) ◽  
Keyword(s):  
Melting Point ◽  
Liquid Metal ◽  
Physical Properties ◽  
Tensile Properties ◽  
Eutectic Alloy ◽  
Heat Treating ◽  
Tube Bending ◽  
Metal Products

Abstract CERROTRU Alloy is a bismuth-base eutectic alloy that melts at 281 F (138 C). It has the highest melting point of the bismuth-base alloys commonly used in industry. It provides production engineers with an easily castable material that is ready for use soon after it freezes. The alloy can be recovered easily and recycled into new uses any number of times. Cerrotru alloy has many uses including anchoring, molds for plastics, filler for tube bending and liquid metal in heat treating. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on casting, heat treating, and machining. Filing Code: Bi-15. Producer or source: Cerro Metal Products.

Systematic calculations of energy levels and transitions rates in Mo XXVIII

2020 ◽  
Vol 75 (8) ◽  
pp. 739-747
Author(s):  
Feng Hu ◽  
Yan Sun ◽  
Maofei Mei
Keyword(s):  
Energy Levels ◽  
Oscillator Strengths ◽  
Atomic Data ◽  
Data Sets ◽  
Electron Systems ◽  
Excitation Energies ◽  
Experimental Values ◽  
Qed Effects ◽  
Hyperfine Structures ◽  
Good Agreement

AbstractComplete and consistent atomic data, including excitation energies, lifetimes, wavelengths, hyperfine structures, Landé gJ-factors and E1, E2, M1, and M2 line strengths, oscillator strengths, transitions rates are reported for the low-lying 41 levels of Mo XXVIII, belonging to the n = 3 states (1s22s22p6)3s23p3, 3s3p4, and 3s23p23d. High-accuracy calculations have been performed as benchmarks in the request for accurate treatments of relativity, electron correlation, and quantum electrodynamic (QED) effects in multi-valence-electron systems. Comparisons are made between the present two data sets, as well as with the experimental results and the experimentally compiled energy values of the National Institute for Standards and Technology wherever available. The calculated values including core-valence correction are found to be in a good agreement with other theoretical and experimental values. The present results are accurate enough for identification and deblending of emission lines involving the n = 3 levels, and are also useful for modeling and diagnosing plasmas.

scholarly journals DFT calculation and assignment of vibrational spectra of aryl and alkyl chlorophosphates

2014 ◽  
Vol 12 (2) ◽  
pp. 153-163
Author(s):  
Viktor Anishchenko ◽  
Vladimir Rybachenko ◽  
Konstantin Chotiy ◽  
Andrey Redko
Keyword(s):  
Vibrational Spectra ◽  
Basis Sets ◽  
Heavy Atoms ◽  
Wide Range ◽  
Complete Assignment ◽  
Key Factor ◽  
Polarization Functions ◽  
Experimental Values ◽  
Semi Empirical ◽  
Good Agreement

AbstractDFT calculations of vibrational spectra of chlorophosphates using wide range of basis sets and hybrid functionals were performed. Good agreement between calculated and experimental vibrational spectra was reached by the combination of non-empirical functional PBE0 with both middle and large basis sets. The frequencies of the stretching vibrations of the phosphate group calculated using semi-empirical functional B3LYP for all basis sets deviate significantly from the experimental values. The number of polarization functions on heavy atoms was shown to be a key factor for the calculation of vibrational frequencies of organophosphates. The importance of consideration of all the stable rotamers for a complete assignment of fundamental modes was shown.

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