Influence of the Two-Dimensional Compressibility on the Surface Pressure Isotherm and Dilational Elasticity of Dodecyldimethylphosphine Oxide

Recently some data from tests done on a cambered plate have been published. The shape of metal plate aerofoil tested matched that taken up by a flexible two-dimensional sail. The most striking result in the rneasurements was the waviness present near the leading edge in the upper surface pressure distribution. To find the theoretical conditions under which such a waviness would occur a parabolic skeleton aerofoil was investigated, as this shape differed little from the actual aerofoil tested.

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Some numerical experiments on firn ventilation with heat transfer

Annals of Glaciology ◽

10.1017/s0260305500011435 ◽

1993 ◽

Vol 18 ◽

pp. 161-165 ◽

Cited By ~ 20

Author(s):

M.R. Albert

Keyword(s):

Heat Transfer ◽

Surface Pressure ◽

Thermal Effects ◽

Numerical Experiments ◽

Temperature Gradients ◽

Pressure Amplitude ◽

Two Dimensional ◽

One Dimensional ◽

Thermal Signature ◽

Spatially Varying

Preliminary estimates of the thermal signature of ventilation in polar firn are obtained from two-dimensional numerical calculations. The simulations show that spatially varying surface pressure can induce airflow velocities of 10−5m s−1at 1.5 m depth in uniform firn, and higher velocities closer to the surface. The two-dimensional heat-transfer results generally agree with our earlier one-dimensional conclusions that the thermal effects of ventilation tend to decrease the temperature gradient in the top portions of the pack. Field observations of ventilation through temperature measurements are most likely to be observed when the firn temperature at depths on the order of 10 m is close to the air temperature, since steep temperature gradients can mask the thermal effects of ventilation. Preliminary indications are that, as long as surface-pressure amplitude is sufficient to move the air about in the top tens of centimeters in the snow, the resulting temperature profile during ventilation is fairly insensitive to the frequency of the surface-pressure forcing for pressure frequencies in the range 0.1–10.0 Hz.

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Waveless Free-Surface Pressure Distributions

Journal of Ship Research ◽

10.5957/jsr.1985.29.3.151 ◽

1985 ◽

Vol 29 (03) ◽

pp. 151-158

Author(s):

J.-M. Vanden Broeck ◽

E. O. Tuck

Keyword(s):

Free Surface ◽

Surface Pressure ◽

Free Surface Flows ◽

Two Dimensional ◽

Surface Flows ◽

Pressure Distributions ◽

Potential Applications ◽

Linear And Nonlinear ◽

Uniform Stream

Linear and nonlinear studies are made of two-dimensional free-surface flows under gravity, in which a disturbance is caused to an otherwise uniform stream by a distribution of pressure over the free surface. In general, such a disturbance creates a system of trailing waves. There are special disturbances that do not, however, and some categories of such disturbances are discussed here. This work has potential applications to design of splashless ship bows.

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Experimental determination of the temperature-concentration diagram of Daoud and Jannink in two-dimensional space by surface pressure measurements

Macromolecules ◽

10.1021/ma00240a025 ◽

1983 ◽

Vol 16 (6) ◽

pp. 956-961 ◽

Cited By ~ 26

Author(s):

Masami Kawaguchi ◽

Akira Yoshida ◽

Akira Takahashi

Keyword(s):

Experimental Determination ◽

Surface Pressure ◽

Dimensional Space ◽

Pressure Measurements ◽

Two Dimensional

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Wake dynamics and surface pressure variations on two-dimensional normal flat plates

AIP Advances ◽

10.1063/1.5079634 ◽

2019 ◽

Vol 9 (4) ◽

pp. 045209 ◽

Cited By ~ 1

Author(s):

Arman Hemmati ◽

David H. Wood ◽

Robert J. Martinuzzi

Keyword(s):

Surface Pressure ◽

Two Dimensional ◽

Flat Plates

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Numerical Simulation on the Dynamic Stall of the Horizontal-Axis Wind Turbine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.1888 ◽

2013 ◽

Vol 448-453 ◽

pp. 1888-1891

Author(s):

Da Fei Guo ◽

Jian Xiang Xu ◽

Ju Yuan

Keyword(s):

Numerical Simulation ◽

Wind Turbine ◽

Surface Pressure ◽

Pressure Coefficient ◽

Static Condition ◽

Attack Angle ◽

Dynamic Stall ◽

Incoming Flow ◽

Two Dimensional ◽

Horizontal Axis Wind Turbine

With the variation of the unsteady incoming flow and impeller rotation, when attack angles of the incoming flow is bigger than the critical angle of attack, there are unsteady separation and dynamic stall on the pressure surface of the impeller. Dynamic stalls are of common occurrence during wind turbines operation. And the aerodynamic characteristics and efficiency of wind turbine are largely affected by the dynamic stall.Therefore,the study of dynamic stall has a great significance over the optimization design of the wind turbine. The paper performs numerical simulation in the dynamic stalls of the 1.2MW horizontal-axis wind turbine, comparing the stalling difference between two-dimensional static and rotating condition. Besides, it also contrasts the stalling condition surface pressure coefficient along the different blade spanwise sections in rotating condition of the same attack angle. And the finding is that the attack angles in rotating condition is bigger than that in the two-dimensional static condition; the surface pressure coefficient is almost equivalent in static and rotating condition when attack angle is smaller than stalling angle; the peak of negative pressure at the leading edge of blade in rotating condition is far bigger than the peak of negative pressure in static condition when attack angle is smaller than static stalling angle. Airflow stall delay occurs when near the blade root. Stall delay phenomenon gradually weakened along the direction of blade radius.

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Surface Pressure Dependence of A-T Isobars and Two-Dimensional Thermal Expansion coefficient of Insoluble Monolayers of Tristearin at the Air/Water Interface

Chemistry Letters ◽

10.1246/cl.1989.1773 ◽

1989 ◽

Vol 18 (10) ◽

pp. 1773-1774 ◽

Cited By ~ 2

Author(s):

Teiji Kato ◽

Katsunori Ohshima ◽

Masatoshi Arai

Keyword(s):

Thermal Expansion ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Surface Pressure ◽

Pressure Dependence ◽

Water Interface ◽

Two Dimensional ◽

Air Water Interface

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Wave resistance: Some cases of three-dimensional fluid motion

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1919.0014 ◽

1919 ◽

Vol 95 (670) ◽

pp. 354-365 ◽

Cited By ~ 29

Keyword(s):

Surface Pressure ◽

Fluid Motion ◽

Three Dimensional ◽

Wave Resistance ◽

The Other ◽

Two Dimensional ◽

Pressure System ◽

Submerged Body ◽

Submerged Sphere ◽

The Waves

1. Calculations of wave resistance, corresponding to a pressure system travelling over the surface, have hitherto been limited to two-dimensional fluid motion; in those cases, the distribution of pressure on the surface is one-dimensional, and the regular waves produced have straight, parallel crests. The object of the following paper is to work out some cases when the surface pressure is two-dimensional and the wave pattern is like that produced by a ship. A certain pressure system symmetrical about a point is first examined, and more general distributions are obtained by superposition. By combining two simple systems of equal magnitude, one in rear of the other, we obtain results which show interesting interference effects. In similar calculations with line pressure systems, at certain speeds the waves due to one system cancel out those due to the other, and the wave resistance is zero; the corresponding ideal form of ship has been called a wave-free pontoon. Such cases of perfect interference do not occur in three-dimensional problems; the graph showing the variation of wave resistance with velocity has the humps and hollows which are characteristic of the resistance curves of ship models. Although the main object is to show how to calculate the wave resistance for assigned surface pressures of considerable generality, it is of interest to interpret some of the results in terms of a certain related problem. With certain limitations, the waves produced by a travelling surface pressure are such as would be caused by a submerged body of suitable form. The expression for the wave resistance of a submerged sphere, given in a previous paper, is confirmed by the following analysis. It is also shown how to extend the method to a submerged body whose form is derived from stream lines obtained by combining sources and siuks with a uniform stream; in particular, an expression is given for the wave resistance of a prolate spheroid moving in the direction of its axis.

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