Properties of Ahlfors constant in Ahlfors covering surface theory

A lifting surface theory is developed to predict the unsteady three-dimensional aerodynamic characteristics for a rotating subsonic annular cascade of swept blades. A discrete element method is used to solve the integral equation for the unsteady blade loading. Numerical examples are presented to demonstrate effects of the sweep on the blade flutter and on the acoustic field generated by interaction of rotating blades with a convected sinusoidal gust. It is found that increasing the sweep results in decrease of the aerodynamic work on vibrating blades and also remarkable reduction of the modal acoustic power of lower radial orders for both forward and backward sweeps.

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ON A PROBLEM OF MAZURKIEWICZ CONCERNING THE BOUNDARY OF A COVERING SURFACE

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.45.1.50 ◽

1959 ◽

Vol 45 (1) ◽

pp. 50-54

Author(s):

P. Seibert

Keyword(s):

Covering Surface

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The influence of rectangular shape holes on energy intensity of grinding grain

Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair) ◽

10.33920/sel-10-2112-03 ◽

2021 ◽

pp. 18-23

Author(s):

A. V Cherepkov ◽

I. V. Konoshin

Keyword(s):

Gastric Juice ◽

Specific Energy ◽

Energy Intensity ◽

Conversion Coefficient ◽

Grinding Process ◽

Theoretical Evaluation ◽

Surface Theory ◽

Rectangular Shape ◽

German Scientist ◽

Circular Shape

Grain before feeding to animals exposed to grinding with the purpose of increasing its digestibility. As a result of this increases the area of interaction of the feed with the gastric juice and decreases the conversion coefficient. Surface theory formulated by German scientist Rittinger, suggests that the work of AR required for the grinding process is directly proportional to newly formed surface. The purpose of this paper is a theoretical evaluation of the intensity of grinding with the use of sieves with rectangular and circular shape holes. When getting groats with the same grinding module by the use of sieves with holes of rectangular shape, one should expect the decrease of specific energy intensity. By reducing the content of dust-like fractions and reduce the total surface feed should be expected to reduce the energy intensity of pneumo transportation.

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