Measurement of large plane surface shape with interferometric aperture synthesis

1992 ◽  
Author(s):  
Masashi Otsubo ◽  
Katsuyuki Okada ◽  
Jumpei Tsujiuchi
Keyword(s):  
Plane Surface ◽  
Aperture Synthesis ◽  
Surface Shape ◽  
Large Plane

Radetzky: a new, large grazing incidence interferometer for large plane surface testing

2008 ◽  
Author(s):  
Emilio Molinari ◽  
Paolo Spanò ◽  
Giorgio Toso ◽  
Daniela Tresoldi ◽  
Roberto Biasi ◽  
...  
Keyword(s):  
Plane Surface ◽  
Grazing Incidence ◽  
Large Plane ◽  
Surface Testing

Analysis of Coolant Entrance Boundary Shape of Porous Region to Control Cooling Along Exit Boundary

1983 ◽  
Vol 105 (3) ◽  
pp. 513-518 ◽  
Author(s):  
R. Siegel ◽  
A. Snyder
Keyword(s):  
Heat Flux ◽  
Path Length ◽  
Flow Resistance ◽  
Plane Surface ◽  
Three Dimensional ◽  
Flow Distribution ◽  
Surface Shape ◽  
Porous Region ◽  
Exit Boundary ◽  
Spatially Varying

A cooled porous region has a plane surface exposed to a specified spatially varying heat flux. The coolant leaves the region through this surface, and it is desired to control the flow distribution to maintain a specified uniform surface temperature. This is accomplished by having the coolant entrance surface shaped to provide in the region the necessary variation of path length and, hence, flow resistance. The surface shape at the coolant entrance is found by solving a Cauchy boundary value problem. An exact solution is obtained that will deal with a wide variety of heating distributions for both two- and three-dimensional shapes.

Analysis of a New Processing Method for Small Curvature Aaspheric

2015 ◽  
Vol 1089 ◽  
pp. 309-314
Author(s):  
Xiu Hua Fu ◽  
Yang Liu ◽  
Zong He Jia
Keyword(s):  
Single Crystal ◽  
Plane Surface ◽  
Single Crystal Silicon ◽  
Processing Method ◽  
Surface Shape ◽  
Shape Error ◽  
Processing Efficiency ◽  
Crystal Silicon ◽  
Performance Curves ◽  
New Processing

For the aspheric processing is complex , time consuming and difficult to guarantte the eccentricity ,this paper introduce a new method of aspheric processing --repairing and polishing methed and describe the principle . Best fit radius, removal function were computed by mathematical model method and the respective performance curves were given by simulation. This methed has the particular advantage of shortening the working time ,reducing the eccentric amount of the element and improving the processing efficiency. Through this processing method, do a series of processing experiments on the smaller aspheric tolerance single crystal silicon aspheric.As the result indicated , plane surface shape error PV 0.52 μm,surface roughness RMS value of single-crystal silicon 0.09 μm ,the center deviation was less than1μm and the surface smoothness meet the standard above the grade Π.

A Normal Flat Plate Close to a Large Plane Surface

1982 ◽  
Vol 33 (1) ◽  
pp. 90-104 ◽  
Author(s):  
K.W. Everitt
Keyword(s):  
Boundary Layer ◽  
Flat Plate ◽  
Layer Thickness ◽  
Vortex Shedding ◽  
Boundary Layer Thickness ◽  
Plane Surface ◽  
Surface Boundary ◽  
Plate Height ◽  
Surface Boundary Layer ◽  
Large Plane

SummaryThe flow around a normal flat plate close to a large plane surface has been investigated for a range of boundary-layer thickness on the plane surface of 0.72 to 2.53 times the plate height, h. As the gap between the plate and the plane surface is reduced below about 0.55h vortex shedding from the plate is inhibited by the presence of the plane surface. Boundary layer thickness has little effect on the gap at which this occurs, but does affect the strength and frequency of vortex shedding at greater gaps. As the gap between the plate lower edge and the plane surface is decreased towards the critical value of 0.55h, both vortex strength and Strouhal number are more significantly affected when the approaching boundary layer is thin. It is not clear whether this is a result of shear or increased turbulent intensity.

scholarly journals The adsorption of iodine by potassium iodide

1933 ◽  
Vol 141 (843) ◽  
pp. 217-232 ◽  
Keyword(s):  
Experimental Work ◽  
Low Temperatures ◽  
Small Area ◽  
Capillary Condensation ◽  
Plane Surface ◽  
Previous Treatment ◽  
Monomolecular Layer ◽  
Apparent Area ◽  
Adsorption Of Gases ◽  
Large Plane

Opinion has been divided for some years as to whether the adsorption of a vapour on a solid surface is confined to a monomolecular layer until the vapour pressure reaches the saturation value, or whether multimolecular layers are formed. Experimental work has generally failed to provide an unequivocal answer to this point, often because the true area of the surface of the adsorbent could not be estimated. It is now recognized that the true area of a surface may be many times the apparent area, and the ratio of these will depend on the previous treatment of the surface. The position has been complicated further by the difficulty of determining the amount of adsorption on a small area of a plane surface when the adsorption is so small as to be undetectable without sensitive apparatus; consequently, the bulk of the experimental work has been carried out on finely divided adsorbents, of large surface. This breaking up of the adsorbent, whether accomplished by chemical or mechanical means, is bound to have an unpredictable effect on the ratio of the true to apparent area of the surface, as distinct from the purely geometrical multiplication. The use of porous or finely divided adsorbents may also introduce the additional complication of capillary condensation of vapours in the spaces between the particles. It is clear, as was first emphasized by Langmuir in 1918, that the investigation of adsorption on plane surfaces, using more delicate technique, is the first step towards a solution of the problem. Langmuir measured the adsorption of gases on large plane surfaces of mica, glass and platinum at low temperatures and pressures. He showed that the adsorption reached a maximum, which corresponded to slightly less than one complete monomolecular layer, and that the extent of adsorption was related to the pressure by an equation of the form x = abp /1 + ap where a and b are constants involving the condensation coefficient, the time of life of adsorbed molecules in the surface, and the number of “ adsorbing centres.”

Aperture synthesis in optics

1974 ◽  
Vol 114 (12) ◽  
pp. 655 ◽  
Author(s):  
V.N. Sintsov ◽  
A.F. Zapryagaev
Keyword(s):  
Aperture Synthesis
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