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Progress in Agricultural Engineering Sciences
Authors: Evgeniy Gennadievich Ivanov, Boris Ivanovich Gorbunov, Alexander Valentinovich Pasin, Boris Alexandrovich Aryutov, and Alexei Ivanovich Novozhilov

Abstract

Background: Acoustic cavitation is the creation and collapse of cavitation caverns in liquid in an acoustic field with a frequency of f = 1–3 kHz. The acoustic-cavitation processes manifest themselves during the collapse phase, with high pressure gradient continuum deformation, with a multiple transformation of energy forms. Liquid whistles are widely used to create an acoustic field of high power, but their efficiency only reaches 6–12%. We propose a liquid whistle in the form of a vortex cavitator (analogue of the Ranque vortex tube) with a rotating body in which a reduction in the input power is predicted.

Objective: Verification of feasibility of using a rotating body in a vortex cavitator with a rotation co-directional to the operational pump impeller.

Method: The method for identifying the feasibility of using a rotating body is to exclude body from the prototype and directly connect vortex chamber outlet with the pump inlet, which ensures the most complete preservation of co-directional vortex component of the flux entering the pump impeller.

Results: The results of experimental studies confirmed the validity of the hypothesis to a greater extent, since we achieved an increase in pressure at the outlet of the pump and a decrease in power at the drive relative to the original design.

Conclusions: The feasibility of designing the vortex cavitator body with rotation capability has been established, which will provide a reduction in input power of at least 30% by a rotation of the body, co-directional with the impeller.

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. Talaj-és trágyavizsgálati módszerek 1962 Collins, H. P., Rasmussen, P. E. and Douglas, C. L., 1992. Crop rotation and

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Dale, J. E., Chandler, J. M. (1979): Herbicide-crop rotation for Johnson grass ( Sorghum halopense ) control. Weed Sci. , 27 , 479–486. Chandler J. M. Herbicide

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Abstract  

Standard entropies of adsorption (Δs 0) of CO on different materials (Cu catalysts, Au catalysts, ZnO and to TiO2) are obtained from static adsorption microcalorimetry, adsorption isobars and temperature-programmed desorption, based on the thermodynamics of adsorption on energetically heterogeneous surfaces. Vibrational entropies of the surfaces s vib α are normally between the rotational and the standard translational entropy of CO in gas phase, and decrease with increasing adsorption energy, which agrees with the explanation of statistical thermodynamics. Δs 0 reflects both the mobility of adsorbates and the specific adsorbate-adsorbent interaction. Limits for reasonable values of the entropy of adsorption are proposed.

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Abstract  

The infusion rate of a slug of tracer into an anchor agitated 100-liter batch mixer was characterized by a decay rate constant. This constant was then used to define a dimensionless mixing-rate number which was related to the stirrer Reynolds number. This correlationship allows the calculation of time or rotational speed needed to achieve any desired degree of uniformity of the mixture.99mTc was used as radiotracer and the mixing process was followed by a scintillation Nal(Tl) counter situated on the reactor wall near the injection point.

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On the basis of the conditionD 2.∀Pr>0;U r (P)P G={P} by L. Fejes Tóth we test two-dimensional motion groups with rotations of the pseudoeuclidean plane forD 2-discreteness. Using an ergodic measure on the torus we will show that these groups aren'tD 2-discrete.

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Abstract  

The method of non-destructive analysis for Al, Si and O in non-metallic inclusions isolated from steel is presented. The small powdered samples varying in mass from 2 mg to 40 mg were analysed, thus making the development of a proper technique of sample preparation necessary. The specific activation geometry and rotation of samples during irradiation were chosen to improve the accuracy and precision. Lower limits of determination for Al, Si, and O were: 1.4 mg, 0.3 mg, and 0.8 mg, respectively.

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In this paper, a new technical solution is introduced for the substrate mixing in a digester. The novelty content lies in the direction changes of the gravitational forces that influence the movement of organic and mineral biomass fractions. Digester case is designed as a horizontal cylinder rotating around a horizontal axis. Digester rotates in water that is in the outer casing.

This design creates a lift force for rotating digester which reduces the load on the bearings. The friction is reduced and therefore it reduces the energy loss of digester rotation and mixing of the substrate.

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Two new periodical space-filling mosaics will be constructed. These are based on a 3D model of the 10D cube. The initial edges have the same lengths and are placed rotation symmetrically around an axis, thus the model is a specifically arranged zonotope. Each mosaic consists of this model and some derived ones of lower-dimensional parts of the 10D cube. These two tessellations complete the construction series based on similar models of 3-12D cubes except the 11D one.

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Abstract  

Precipitation of a sparingly soluble salt in the annular gap of a continuous Couette reactor with two unpremixed feeds has been experimentally investigated. Barium chloride and sodium sulphate in stoichiometric ratio are fed at different flow rate in the lower part of the reactor; different feeding modes have been considered. The dependence of precipitation yield, mean crystal size and particle size distribution on rotation speed, axial flow rate and initial supersaturation ratio has been studied. Depending on the operating conditions crystals with different morphologies have been obtained, varying from dentritic tabular crystals to complex pyramidal ones and from single crystals to aggregates.

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