Theoretical Modeling of TLD With Different Tank Geometries Using Linear Long Wave Theory

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
X. Deng ◽  
M. J. Tait
Keyword(s):  
Effective Mass ◽  
Virtual Work ◽  
Damping Ratio ◽  
Wave Theory ◽  
Mass Ratio ◽  
Flat Bottom ◽  
Tuned Liquid Dampers ◽  
Long Wave ◽  
Effective Mass Ratio ◽  
Energy Dissipated

This study focuses on the modeling of tuned liquid dampers (TLDs) with triangular-bottom, sloped-bottom, parabolic-bottom, and flat-bottom tanks using the linear long wave theory. The energy dissipated by damping screens is modeled theoretically utilizing the method of virtual work. In this proposed model, only the fundamental sloshing mode is considered, and the assumption of small free surface fluid response amplitude is made. Subsequently, the equivalent mechanical properties including effective mass, natural frequency, and damping ratio of the TLDs, having different tank geometries, are compared. It is found that the normalized effective mass ratio values for a parabolic-bottom tank and a sloped-bottom tank with a sloping angle of 20 deg are larger than the normalized effective mass ratio values for triangular-bottom and flat-bottom tanks. An increase in the normalized effective mass ratio indicates that a greater portion of the water inside the tank participates in the sloshing motion. The derived equivalent mechanical models for the TLD tank geometries considered in this study can be used for the preliminary design of structural-TLD systems.

Equivalent mechanical models of tuned liquid dampers with different tank geometries

2008 ◽  
Vol 35 (10) ◽  
pp. 1088-1101 ◽  
Author(s):  
X. Deng ◽  
M. J. Tait
Keyword(s):  
Mechanical Properties ◽  
Effective Mass ◽  
Virtual Work ◽  
Damping Ratio ◽  
Tuned Liquid Damper ◽  
Equivalent Viscous Damping ◽  
Tuned Liquid Dampers ◽  
Mechanical Models ◽  
Sloshing Mode ◽  
Liquid Dampers

This paper focuses on the development of equivalent mechanical models for tuned liquid dampers (TLDs) with rectangular, vertical-cylindrical, horizontal-cylindrical, and hyperboloid (conical) tank shapes under external excitation in the transverse direction. Potential flow theory is utilized to obtain the free-surface response amplitude and the corresponding velocity of the sloshing liquid and Lagrange’s equations are used to determine the generalized properties. Morison’s equation and the virtual work method are used to estimate an equivalent viscous damping ratio based on the screen loss coefficient. The equivalent mechanical properties derived in this paper model the fundamental sloshing mode only and are restricted to small response amplitudes. Subsequently, the equivalent mechanical properties including effective mass, natural frequency, and damping ratio of the TLDs, having different tank geometries, are compared. It is found that the effective mass values for horizontal-cylindrical and hyperboloid TLDs are larger than the effective mass values for vertical-cylindrical and rectangular TLDs. The increased effective mass values for horizontal-cylindrical and hyperboloid TLDs can result in improved tuned liquid damper performance given the same total liquid mass as that of rectangular or vertical-cylindrical TLDs.

de Haas–van Alphen Effect and Localized Spin Fluctuations in Dilute Al–Mn Alloys

1971 ◽  
Vol 49 (13) ◽  
pp. 1813-1822 ◽  
Author(s):  
B. E. Paton
Keyword(s):  
Effective Mass ◽  
Localized States ◽  
Spin Fluctuations ◽  
Mass Ratio ◽  
Electron Phonon Interaction ◽  
Impurity Atoms ◽  
Localized State ◽  
Effective Mass Ratio ◽  
Field Modulation ◽  
Impurity Sites

The de Haas–van Alphen effect in dilute alloys of aluminum-manganese has been measured using the field modulation technique at magnetic fields up to 60 kG and temperatures between 1.1 and 4.2 °K. The period, effective mass ratio, and collision parameter of the third zone y orbits were found to increase linearly on alloying. The increase in the collision parameter attributed to the resonant d scattering by the localized states on the impurity atoms was found to be approximately 10 times larger than the increase observed in aluminum alloys with nontransition element impurities. The effective mass ratio was shown to be enhanced by the electron–phonon interaction and by the localized spin fluctuations on the impurity sites. The parameters which describe the localized state were calculated from the experimental results in the framework of a renormalized theory of localized spin fluctuations and were found to be in agreement with similar parameters calculated from other physical properties. The de Haas–van Alphen results are consistent with the conclusion that the localized state of manganese impurities in aluminum are nonmagnetic but strongly enhanced by localized spin fluctuations.

scholarly journals Midlatitude Baroclinic Rossby Waves in a High-Resolution OGCM Simulation

2009 ◽  
Vol 39 (9) ◽  
pp. 2264-2279 ◽  
Author(s):  
Kunihiro Aoki ◽  
Atsushi Kubokawa ◽  
Hideharu Sasaki ◽  
Yoshikazu Sasai
Keyword(s):  
Rossby Wave ◽  
Vertical Structure ◽  
Phase Speed ◽  
Wave Theory ◽  
Bottom Pressure ◽  
Background Flow ◽  
Flat Bottom ◽  
Long Wave ◽  
Wavenumber Spectrum ◽  
Dominant Peak

Abstract The effects of background baroclinic zonal flow and bottom pressure decoupling on midlatitude oceanic Rossby wave dynamics using a high-resolution OGCM simulation are investigated. To examine these effects, the phase speed and vertical structure of the simulated wave are compared with each of the different linear Rossby wave solutions obtained for two different circumstances (with or without background flow) and two different boundary conditions (a flat bottom or a bottom pressure decoupling condition). First, a frequency–wavenumber spectrum is examined for depth anomaly of the permanent thermocline (27.0σθ surface) along 32°S. Most of the energy is distributed along the theoretical dispersion curve including the effects of background flow and bottom pressure decoupling. The authors focus on a secondary dominant peak (appearing at a frequency greater than 1 cycle per year) at which the differences between the dispersion curves are large enough to discuss the relation between the spectral peak and the dispersion curves. The phase speed of this peak is nearly 1.5 times larger than that of the standard long-wave theory (flat bottom and no background flow), which is similar to results from previous observational studies. The extended long-wave theory including background flow and bottom pressure decoupling effects overestimates the phase speed. However, taking into account finite wavelength effects, this theory provides a phase speed much closer to that of the secondary dominant peak. The vertical structure corresponding to the wave of the secondary dominant peak extracted by composite analysis is intensified in the surface layer, a result similar to that from the theory including background flow and bottom pressure decoupling effects. The authors also compare the latitudinal distribution of midlatitude phase speed estimated by the frequency–wavenumber spectrum with theoretical results. The theory including background flow, bottom pressure decoupling, and finite wavelength effects reproduces the latitudinal distribution well, suggesting that these effects are important for explaining Rossby wave speed. The dominant factor enhancing the phase speed is bottom pressure decoupling related to rough bottom topography, while north of 30°N the background flow makes a strong contribution to the phase speed enhancement.

Transport properties of tungsten-doped VO2

1976 ◽  
Vol 54 (4) ◽  
pp. 408-412 ◽  
Author(s):  
J. M. Reyes ◽  
M. Sayer ◽  
R. Chen
Keyword(s):  
Transport Properties ◽  
Effective Mass ◽  
Conduction Band ◽  
Ac Conductivity ◽  
Impurity Content ◽  
Donor Level ◽  
Mass Ratio ◽  
Compensation Ratio ◽  
Dc And Ac Conductivity ◽  
Effective Mass Ratio

Measurements of DC and AC conductivity and thermopower show that VO2: W can be treated as a conventional n-type extrinsic semiconductor with a donor level 0.06–0.08 eV below the conduction band. For samples with an impurity content from 0.67 → 1.70 at.% W, an effective mass ratio m*/m of 65 ± 10 and a compensation ratio of 0.7 ± 0.1 are deduced from conventional semiconductor theory assuming donor exhaustion just below the metal semiconductor transition.

Measurement of the Modeling Parameters for a Maxiflex “B” Springboard

1990 ◽  
Vol 6 (3) ◽  
pp. 325-335 ◽  
Author(s):  
Eric J. Sprigings ◽  
Denise S. Stilling ◽  
L. Gien Watson ◽  
Paul D. Dorotich
Keyword(s):  
Effective Mass ◽  
Spring Stiffness ◽  
Mass Ratio ◽  
Characteristic Modeling ◽  
Effective Mass Ratio ◽  
Local Stiffness

The characteristic modeling parameters (spring stiffness and effective mass ratio) were determined experimentally for a Maxiflex “B” board. The results indicated that the Maxiflex “B” board was substantially less stiff than a Duraflex board. Most of this decrease in stiffness is a result of the added second taper in the Maxiflex “B” board. Calculations, based on theory, revealed that the perforations in the Maxiflex “B” board reduced the local stiffness over the end region of the board by an additional 10%. As a result of its greater compliancy, the Maxiflex board also had an effective mass ratio that was greater than that of the Duraflex. It was clear from these experiments that the acknowledged superiority of the Maxiflex “B” board over the Duraflex could be attributed directly to the increased compliancy found in the Maxiflex “B” board.

Nanotechnology, Long Waves, and Future of Manufacturing Industry

2020 ◽  
pp. 2053-2080
Author(s):  
Cem Okan Tuncel ◽  
Ayda Polat
Keyword(s):  
Manufacturing Industry ◽  
Wave Theory ◽  
Comparative Case Study ◽  
Industrialized Countries ◽  
Capitalist Development ◽  
Mena Countries ◽  
Newly Industrialized Countries ◽  
Long Wave ◽  
The Impact

This study concerns the long wave theory of capitalist development with an aim to discuss and analyze the impact of nanotechnology on manufacturing industry. Long wave theory was asserted by Russian economist Kondratieff and it states the capitalist development with subsequent cycles which last 40 to 60 years each. The theory of Kondratieff was also contributed by other scholars as Schumpeter, Freeman, and Perez. Our research attempts to review how nanotechnology contributes economic growth, and how it changes the structure of manufacturing industry at the eve of the sixth Kondratieff wave. This structure was examined by using comparative case study of European Union, East Asian Newly Industrialized Countries and Middle East and North African (MENA) countries.

scholarly journals RUN-UP OF PERIODIC WAVES ON BEACHES OF NON-UNIFORM SLOPE

1984 ◽  
Vol 1 (19) ◽  
pp. 23 ◽  
Author(s):  
Yoshinobu Ogawa ◽  
Nobuo Shuto
Keyword(s):  
Experimental Data ◽  
Wave Theory ◽  
Breaking Waves ◽  
Lagrangian Description ◽  
Periodic Waves ◽  
Swash Zone ◽  
Slope Method ◽  
Long Wave ◽  
Run Up ◽  
Better Than

Run-up of periodic waves on gentle or non-uniform slopes is discussed. Breaking condition and run-up height of non-breaking waves are derived "by the use of the linear long wave theory in the Lagrangian description. As to the breaking waves, the width of swash zone and the run-up height are-obtained for relatively gentle slopes (less than 1/30), on dividing the transformation of waves into dissipation and swash processes. The formula obtained here agrees with experimental data better than Hunt's formula does. The same procedure is applied to non-uniform slopes and is found to give better results than Saville's composite slope method.

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