scholarly journals THE THRESHOLD OP MOVEMENT OP COARSE MATERIAL IN OSCILLATORY PLOW

1968 ◽  
Vol 1 (11) ◽  
pp. 30 ◽  
Author(s):  
P.J. Rance ◽  
N.F. Warren
Keyword(s):  
Wave Action ◽  
Oscillatory Motion ◽  
Experimental Results ◽  
Basic Material ◽  
Water Tunnel ◽  
Period Range ◽  
Water Motion ◽  
Coarse Material ◽  
Sea Bed

Experimental results are presented from which it is now possible to predict the threshold of movement of shingle. The experiments were conducted in an Oscillating Water Tunnel, (Ref. 1), on the threshold of movement of shingle size material. The Tunnel simulates the oscillatory water motion at the sea bed due to wave action with a semi-orbit range of 0-4.5 metres and a period range of 5-15 seconds. Additionally, a unidirectional current of up to 0.6 m/sec can also be superposed upon the oscillatory motion. Although limestone chips of between 0.32 cm and 2.5 cm diameters were the basic material tested, other materials such as coal and sand were examined in order to observe the effects of the various parameters over a wider range.

scholarly journals SEDIMENT THRESHOLD UNDER OSCILLATORY WAVES

1974 ◽  
Vol 1 (14) ◽  
pp. 44 ◽  
Author(s):  
Paul D. Komar ◽  
Martin C. Miller
Keyword(s):  
Wave Action ◽  
Water Motion ◽  
Sediment Threshold ◽  
Oscillatory Waves

As the velocity of the water motion near the bottom under oscillatory waves is increased, there comes a stage when the water exerts a stress on the particles sufficient to cause them to move. This study reviews data on threshold of sediment motion under wave action and compares the results with the established curves for threshold under a unidirectional current.

scholarly journals ANALYSIS OF PERMEABLE BREAKWATERS

1986 ◽  
Vol 1 (20) ◽  
pp. 155
Author(s):  
Hitoshi Murakami ◽  
Yoshihiko Hosoi ◽  
Yoshitaka Goda
Keyword(s):  
Cross Section ◽  
Water Exchange ◽  
Water Concentration ◽  
Wave Action ◽  
Theoretical Solution ◽  
Experimental Results ◽  
Concentration Change ◽  
Vertical Slit ◽  
Transmission Coefficients ◽  
The Cross

This paper discusses the characteristics of hydraulic and water exchange due to the wave action against vertical slit-type breakwaters. The theoretical solution of the reflection and the transmission coefficients for the breakwater models is compared with the experimental results. Furthermore, the water exchange discharge and the water concentration change through the gap of the permeable breakwater are examined experimentally. Finally the most effective geometry of the cross section is suggested for the breakwaters used here.

scholarly journals DYNAMICS OF VIBRA AMICS OF VIBRATIONAL MOTION OF THE DOM TION OF THE DOMAIN BORDER AIN BORDER IN THE FERRITE GRADE OF Tb3Fe5O12

2019 ◽  
Vol 3 (3) ◽  
pp. 6-10
Author(s):  
Davron Rakhmonovich Dzhuraev ◽  
◽  
Mirzo Zokirovich Sharipov ◽  
Dilshod Ergashovich Khaitov ◽  
Nilufar Mansurovna Ergasheva
Keyword(s):  
Theoretical Model ◽  
Magnetic Resonance ◽  
Resonance Frequency ◽  
Optical Method ◽  
Oscillatory Motion ◽  
Experimental Results ◽  
Compensation Point ◽  
Vibrational Motion ◽  
Magnetic Compensation ◽  
Domain Boundaries

The magneto-optical method is used to study the dynamics of the oscillatory motion of domain boundaries in a Tb3Fe5O12 garnet ferrite in the temperature range 200-295K, including the magnetic compensation point of this ferrimagnet Fs ≈ 249K. To interpret the experimental results obtained, a theoretical model of magnetic resonance of domain boundaries is proposed, according to which when the temperature approaches the compensation point, the mass of the domain boundaries tends to infinity, and the resonance frequency tends to zero

scholarly journals FLEXIBLE POROUS FLOATING BREAKWATERS

1968 ◽  
Vol 1 (11) ◽  
pp. 69 ◽  
Author(s):  
R.J. Kennedy ◽  
J. Marsalek
Keyword(s):  
Empirical Equation ◽  
Wave Theory ◽  
Ocean Waves ◽  
Systematic Investigation ◽  
Wave Action ◽  
Experimental Results ◽  
Model Scale ◽  
Floating Breakwaters

Observation of the effect of towed rafts of pulpwood on lake and ocean waves led to a systematic investigation at model scale. An empirical equation compatible with wave theory was devised and lines representing this equation together with points representing experimental results are shown for different conditions. An example of the application of the equation to prototype wave action is given. Four box booms with porous fronts, arranged m series, were substituted for the model pulpwood gam and proved to be effective m damping waves.

Torsional Flutter in Stalled Cascade

1978 ◽  
Vol 100 (2) ◽  
pp. 317-325 ◽  
Author(s):  
S. Yashima ◽  
H. Tanaka
Keyword(s):  
Theoretical Study ◽  
Experimental Results ◽  
Water Tunnel ◽  
Computational Results ◽  
Linear Cascade ◽  
Singularity Method ◽  
Reduced Frequency ◽  
Aerodynamic Moment ◽  
Good Agreement

Applying free streamline theory and singularity method, a theoretical study is developed for the torsional flutter problem in fully stalled cascade. Aerodynamic moment acting on a vibrating blade is calculated for some cascade conditions. Computational results show that critical reduced frequency is much higher in the case of stalled cascade than unstalled cascade and affected by the position of pitching center. Experiments were carried out using a water tunnel with a linear cascade, and the unsteady moment acting on the vibrating blade was measured. Computational and experimental results show fairly good agreement.

Scientific Bases of Water Chemistry for Corrosion Control of NPPs by Integration of Radiation- and Electro-Chemistry

2013 ◽  
Author(s):  
Genn Saji
Keyword(s):  
Hydrogen Peroxide ◽  
Water Chemistry ◽  
Material Balance ◽  
Scientific Basis ◽  
Experimental Results ◽  
Basic Material ◽  
General Interest ◽  
Recent Theory ◽  
Radiation Chemical ◽  
Corrosion Science

In this paper, the author continues his investigation on the scientific basis of water chemistry specifications by applying his recent theory, which integrates the elemental radiation- and electro-chemistry reactions in the “Butlar-Volmer equation.” The B-V equation is well established as the basic material balance equation in corrosion science. The author’s new approach has been compared with the published in-pile test results of the electrochemical potential differences between the in-flux and out-flux regions for both the PWR- and BWR water chemistry environment. Although the theoretical estimation generally reproduced the experimental results, there remains significant deviation from the experimental results at the very low DH region (<10cc-STP/kg-water) in PWRs as well as the low DO region (<10ppb) in BWRs. Although these regions are outside of the water chemistry specifications of general interest, the scientific causes of the deviation must be clarified. In this paper, the author found that the deviations are due to the dominant radiation-chemical reactions involving hydrogen ions and hydrogen peroxide at the lower ends. Although the radiation- and electrochemical reaction was further exploited with respect to the potential differences induced by the hydrogen peroxide, the effects were disappointingly small, when estimated in terms of a mixed potential of the electrode reactions. This leads the author to suspect that hydrogen-ion-radical reactions should be the main causes. Currently further analyses are in progress.

scholarly journals SCALE LAWS FOR BED FORMS IN LABORATORY WAVE MODELS

1974 ◽  
Vol 1 (14) ◽  
pp. 62
Author(s):  
G.R. Mogridge
Keyword(s):  
Experimental Study ◽  
Wave Action ◽  
Water Tunnel ◽  
Wave Flume ◽  
Wide Range ◽  
Bed Forms ◽  
Wave Models

An experimental study of the variables governing the development of bed forms under wave action has been conducted. A wide range of conditions was covered by the use of a wave flume and an oscillating water tunnel. Scale laws for modelling bed forms are developed using the results of these experiments. It is recommended that the model sediment used should be the same density as in the prototype and its size should be scaled geometrically. If this is not practical, it is shown how the scale laws can be used to minimise the distortion of the bed forms produced in the model.

scholarly journals Torsional Flutter in Stalled Cascade

1977 ◽  
Author(s):  
S. Yashima ◽  
H. Tanaka
Keyword(s):  
Theoretical Study ◽  
Experimental Results ◽  
Water Tunnel ◽  
Computational Results ◽  
Linear Cascade ◽  
Singularity Method ◽  
Reduced Frequency ◽  
Aerodynamic Moment ◽  
Good Agreement

Applying free streamline theory and singularity method, a theoretical study is developed for the torsional flutter problem in fully stalled cascade. Aerodynamic moment acting on a vibrating blade is calculated for some cascade conditions. Computational results show that critical reduced frequency is much higher in the case of stalled cascade than unstalled one and affected by the position of pitching center. Experiments were carried out using a water tunnel with a linear cascade, and the unsteady moment acting on the vibrating blade was measured. Computational and experimental results show fairly good agreement.

Oscillatory Motion of Large Pontoon Due to Wave Action

1972 ◽  
Vol 15 (1) ◽  
pp. 95-103
Author(s):  
Masashi Hom-ma ◽  
Kunihiro Ogihara
Keyword(s):  
Wave Action ◽  
Oscillatory Motion

scholarly journals SAND BED-FORM LENGTHS UNDER OSCILLATORY MOTION

1980 ◽  
Vol 1 (17) ◽  
pp. 80 ◽  
Author(s):  
Arthur Brebner
Keyword(s):  
Oscillatory Motion ◽  
Water Tunnel ◽  
Dimensionless Form ◽  
Bed Form ◽  
The Relationship

Tests were carried out in the oscillating water tunnel to determine the bed-form lengths of sand ranging from 0.1 mm to 0.55 mm subjected to oscillatory motion of various orbital diameters ranging from 0.15 m to 1.5 m and of various periods ranging from 3 to 15 s. The relationship for the bed-form length is given in the accompanying graph in dimensionless form.

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