Numerical investigation of light-absorbent convection in horizontal tube I. Steady convection states in the field of continuous laser radiation

1977 ◽  
Vol 33 (4) ◽  
pp. 1224-1231
Author(s):  
B. P. Gerasimov ◽  
V. M. Gordienko ◽  
A. P. Sukhorukov
Keyword(s):  
Laser Radiation ◽  
Numerical Investigation ◽  
Horizontal Tube ◽  
Continuous Laser ◽  
Steady Convection

NUMERICAL INVESTIGATION OF FILM DISTRIBUTION IN HORIZONTAL-TUBE FALLING FILM EVAPORATOR

2011 ◽  
Vol 19 (03) ◽  
pp. 177-183 ◽  
Author(s):  
JIN-BO CHEN ◽  
QING-GANG QIU
Keyword(s):  
Numerical Simulation ◽  
Fluid Flow ◽  
Film Thickness ◽  
Liquid Film ◽  
Numerical Investigation ◽  
Horizontal Tube ◽  
Flow Density ◽  
Falling Film ◽  
Film Distribution ◽  
Simulation Results

The technique of horizontal-tube falling film has been used in the cooling and heating industries such as refrigeration systems, heating systems and ocean thermal energy conversion systems. The comprehensive performance of evaporator is directly affected by the film distribution characteristics outside tubes. In this paper, numerical investigation was performed to predict the film characteristics outside the tubes in horizontal-tube falling film evaporator. The effects of liquid flow rate, tube diameter and the circular degree of tube on the film thickness were presented. The numerical simulation results were compared with that of the empirical equations for calculating the falling film thickness, and agreements between them were reasonable. Numerical simulation results show that, at the fixed fluid flow density, the liquid film is thicker on the upper and lower tube and the thinnest liquid film appears at angle of about 120°. The results also indicate that, when the fluid flow density decreases to a certain value, the local dryout spot on the surface of the tube would occur. In addition, the film thickness decreases with the increases of the tube diameter at the fixed fluid flow density.

Multiphoton polymerization with the holographic control of femtosecond and continuous laser radiation

2012 ◽  
Vol 6 (3) ◽  
pp. 357-361 ◽  
Author(s):  
A. D. Zalesskii ◽  
N. A. Danil’chenko ◽  
Yu. V. Barbashov ◽  
B. I. Zapadinskii ◽  
O. M. Sarkisov
Keyword(s):  
Laser Radiation ◽  
Continuous Laser

Properties of the surface of structural materials in the area of a barcode formed under the action of laser radiation

2021 ◽  
Vol 1 ◽  
pp. 15-24
Author(s):  
Yu.R. Kolobov ◽  
◽  
A.E. Ligachev ◽  
Keyword(s):  
Laser Radiation ◽  
Picosecond Laser ◽  
Laser Pulses ◽  
Structural Materials ◽  
Metal Alloys ◽  
Experimental Investigations ◽  
Structure And Properties ◽  
Surface Layers ◽  
Continuous Laser ◽  
Near Surface

A review of experimental investigations of changes in the structure and properties of the surface and near-surface layers of various materials (steels, metal alloys, ceramics and graphite) in the area of a barcode applied by continuous laser radiation and short (nanosecond) and ultrashort (femto- and picosecond) laser pulses.

Semiconductor converters of continuous laser radiation into a pulsed beam

2003 ◽  
Vol 29 (11) ◽  
pp. 886-888
Author(s):  
P. G. Kasherininov ◽  
A. N. Lodygin ◽  
I. S. Tarasov
Keyword(s):  
Laser Radiation ◽  
Continuous Laser ◽  
Semiconductor Converters

scholarly journals Self-diffraction of continuous laser radiation in a disperse medium with absorbing particles

2013 ◽  
Vol 21 (7) ◽  
pp. 8922 ◽  
Author(s):  
O. V. Angelsky ◽  
A. Ya. Bekshaev ◽  
P. P. Maksimyak ◽  
A. P. Maksimyak ◽  
S. G. Hanson ◽  
...  
Keyword(s):  
Laser Radiation ◽  
Disperse Medium ◽  
Continuous Laser

The Effect Of Scattered Radiation On Capabilities Of Laser Beam Guidance

2020 ◽  
pp. 110-117
Author(s):  
Gennady A. Kaloshin ◽  
Vladimir P. Budak ◽  
Sergey A. Shishkin ◽  
Vladislav V. Zhukov
Keyword(s):  
Laser Radiation ◽  
Laser Beam ◽  
Single Scattering ◽  
Remote Detection ◽  
Field Observations ◽  
Continuous Laser ◽  
Axial Zone ◽  
Scattering Approximation ◽  
Detection Capabilities ◽  
Single Scattering Approximation

The paper discusses the possibility of remote detection of a continuous laser beam propagating in a scattering continental and coastal atmosphere, when it is recorded outside the axial zone. In the single scattering approximation, estimates of the radianceat the registration site are carried out, which are compared with the threshold characteristics of existing photodetectors in the visible and IR spectral regions. It is shown that the laser radiation (LR) of the beam is reliably recorded in the range of angles (0–180)° at metrological range of visibility equal (5–20) km at night conditions. At twilight, under the same conditions, detection capabilities are significantly reduced. A significant increase of the LR beam radiance contrast with a decrease in its divergence has been shown experimentally in the field observations. At twilight, a decrease in the beam’s radiance contrast is seen. A beam with a divergence equal to 2 ceases to be distinguishable at angles equal to (80–90)°, and a beam with a divergence of 4 – at angles (60–70)°.In this case, the contrast difference reaches up to 10 times.

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