scholarly journals JUSTIFICATION OF PRINCIPAL DIAGRAM AND STUDY OF THE OPERATING CYCLE OF VOLUMETRIC HYDROPERCUSSIVE MECHANISM

2020 ◽  
Vol 2 ◽  
pp. 153-161
Author(s):  
Vadim V. Plokhikh ◽  
Boris B. Danilov ◽  
Dmitriy O. Cheshchin

The approaches to justification of design diagrams of volumetric hydropercussive machines are presented. Simulation models of hydraulic impact systems are constructed and investigated. It is found that the diagram with an intermediate chamber allows decreasing peak pressure in the idle stroke chamber by two times, compared with the diagram without an intermediate chamber. It is concluded that hydropercussive machine with an elastic valve and intermediate chamber would hardly decrease the velocity of striking part in the end of power stroke.

Author(s):  
Gong Chen

Cylinder peak pressure (pmax) over operating cycle of a high-power turbo-charged compression-ignition engine indicates its in-cylinder combustion behavior and also the level of mechanical load acting on its power assembly components. It is significantly important to understand how pmax with cylinder pressure (p) varies due to possible changes in engine design and operation input condition parameters. The input parameters considered in this paper include piston crank-angle position (θ), compression ratio (CR), amount of cycle burning heat (Q), injection/combustion duration (Δθ), and fuel injection/combustion-start timing (θs). Effects of the input parameters to pmax and θpmax which is the crank-angle position of pmax in engines of this type are analyzed, predicted and characterized. Results with the approaches to achieving those are presented. It is indicated from the results that the crank-angle position of combustion duration (Δθ) has a significant effect on θpmax for a given engine power density. As the position of Δθ varies, θpmax varies accordingly and can be determined. It is also indicated that as θs is sufficiently retarded from a position before the top dead center (TDC) to a point close to TDC, either before or after, in a large-bore high-power turbocharged engine, the trend of pmax variation would be reversed. This establishes the minimum value of pmax over the range of engine combustion-start timing variation. The results and indications are beneficial and usefully needed in adjusting the design and operation input condition parameters for achieving optimized balances between power-output capacity, fuel efficiency, exhaust emissions and mechanical/thermal loading of engines in this type.


Author(s):  
S. Basu ◽  
D. F. Parsons

We are approaching the invasiveness of cancer cells from the studies of their wet surface morphology which should distinguish them from their normal counterparts. In this report attempts have been made to provide physical basis and background work to a wet replication method with a differentially pumped hydration chamber (Fig. 1) (1,2), to apply this knowledge for obtaining replica of some specimens of known features (e.g. polystyrene latex) and finally to realize more specific problems and to improvize new methods and instrumentation for their rectification. In principle, the evaporant molecules penetrate through a pair of apertures (250, 350μ), through water vapors and is, then, deposited on the specimen. An intermediate chamber between the apertures is pumped independently of the high vacuum system. The size of the apertures is sufficiently small so that full saturated water vapor pressure is maintained near the specimen.


Author(s):  
Robert Hard ◽  
Gerald Rupp ◽  
Matthew L. Withiam-Leitch ◽  
Lisa Cardamone

In a coordinated field of beating cilia, the direction of the power stroke is correlated with the orientation of basal body appendages, called basal feet. In newt lung ciliated cells, adjacent basal feet are interconnected by cold-stable microtubules (basal MTs). In the present study, we investigate the hypothesis that these basal MTs stabilize ciliary distribution and alignment. To accomplish this, newt lung primary cultures were treated with the microtubule disrupting agent, Colcemid. In newt lung cultures, cilia normally disperse in a characteristic fashion as the mucociliary epithelium migrates from the tissue explant. Four arbitrary, but progressive stages of dispersion were defined and used to monitor this redistribution process. Ciliaiy beat frequency, coordination, and dispersion were assessed for 91 hrs in untreated (control) and treated cultures. When compared to controls, cilia dispersed more rapidly and ciliary coordination decreased markedly in cultures treated with Colcemid (2 mM). Correlative LM/EM was used to assess whether these effects of Colcemid were coupled to ultrastructural changes. Living cells were defined as having coordinated or uncoordinated cilia and then were processed for transmission EM.


Author(s):  
C. A. Callender ◽  
Wm. C. Dawson ◽  
J. J. Funk

The geometric structure of pore space in some carbonate rocks can be correlated with petrophysical measurements by quantitatively analyzing binaries generated from SEM images. Reservoirs with similar porosities can have markedly different permeabilities. Image analysis identifies which characteristics of a rock are responsible for the permeability differences. Imaging data can explain unusual fluid flow patterns which, in turn, can improve production simulation models.Analytical SchemeOur sample suite consists of 30 Middle East carbonates having porosities ranging from 21 to 28% and permeabilities from 92 to 2153 md. Engineering tests reveal the lack of a consistent (predictable) relationship between porosity and permeability (Fig. 1). Finely polished thin sections were studied petrographically to determine rock texture. The studied thin sections represent four petrographically distinct carbonate rock types ranging from compacted, poorly-sorted, dolomitized, intraclastic grainstones to well-sorted, foraminiferal,ooid, peloidal grainstones. The samples were analyzed for pore structure by a Tracor Northern 5500 IPP 5B/80 image analyzer and a 80386 microprocessor-based imaging system. Between 30 and 50 SEM-generated backscattered electron images (frames) were collected per thin section. Binaries were created from the gray level that represents the pore space. Calculated values were averaged and the data analyzed to determine which geological pore structure characteristics actually affect permeability.


Author(s):  
Marta K. Isaeva

The paper dedicates in commemoration of K.A. Bagrinovsky, known scientist, doctor of economic sciences, professor. His thesis was theoretic problems of mathematical modeling and operation of economy. His works in the operations research, the methods making decision, the simulation were received in scientific world. The analysis and the modeling of the mechanisms for scientific and technological development for the production systems of different level in economic hierarchic both centrally controlled economy and making mechanism were conduced by Bagrinovsky in CEMI RAS. The paper presents the investigations (2001–2015) of the analysis and the simulation of the different mechanisms of the innovational activity. It also discusses the methods of the development the complex of the simulation models. In a sense simulation modeling is the science and the art as the selection of the salient parameters for the construction model, intake simplification, the computer experiment and the making decision based on scarcity of accuracy models rest on the heuristic power of men: the practical trial, the intelligence and the intuition. K.A. Bagrinovsky introduced the considerable endowment in the development of this direction for economic and mathematical investigation.The principal object was to show that the relationship between the innovational policy and the technological structure, scientific research sector and the introducing of the progressive production and the organizational structure is obtainable by the models. The character of these relationships may be to use in control of the parameters for the modernization economic. The construction simulation models and the experimental computation analysis were presented the investigations the different mechanisms of the innovational development ant the variants of the estimation have been accomplished on the modeling level by the computer experiment.


2017 ◽  
Vol 137 (8) ◽  
pp. 1001-1008
Author(s):  
Tadayoshi Kosaka ◽  
Kazuhiko Koyanagi ◽  
Yasutaka Satake ◽  
Isao Kobayashi ◽  
Nobuhiro Matsudaira ◽  
...  

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