scholarly journals Velocity rate of screw streams in the site of submerged vanes

Vestnik MGSU ◽  
2020 ◽  
pp. 859-866
Author(s):  
Alexey V. Klovsky ◽  
Dmitry V. Kozlov
Keyword(s):  
Experimental Data ◽  
Physical Model ◽  
Formation Mechanism ◽  
Theoretical Calculations ◽  
Downstream Face ◽  
Water Separation ◽  
Geometric Characteristics ◽  
Setting Angle ◽  
Graphic Dependence ◽  
Submerged Vanes

Introduction. The formation mechanism of longitudinal screw streams (LSS) along the upstream and downstream face of submerged vanes (SV) is considered. Acting along with the artificial transversal circulation (ATC), these streams protect the water intake from the channel sediments. The intensities and directions of LSS and ATC depend on the regime of flow, the planned-geometric characteristics of the vanes. Recommendations concerning the purpose of SV’s rational characteristics in the aspect of steady formation of all three protective streams in the flow for river damless intakes are contradictory and require clarification. The purpose of the study is to analyze the velocity rate of the LSS in SV site at various planned-geometric characteristics of the vane and hydraulic modes of its operation based on a physical model with an erosion-resistant channel (without water separation), as well as to determine an efficient range of setting angles of the SV’s to the tray board in terms of formation of steady and intensive LSS along the upstream and downstream face of the vane. Materials and methods. Model physical hydraulic studies and theoretical calculations were used. Five hydraulic modes of SV’s operation were studied, with various planned-geometric characteristics, using the physical model with an erosion-resistant channel (without water separation). The obtained experimental data were summarized and analyzed. Results. Results of laboratory hydraulic studies of LSS velocity rate in LSS site were presented. Experimental graphic dependence diagrams were plotted characterizing the intensity and direction of the LSS along upstream and downstream faces of the vane. Conclusions. A determining influence of the setting angle of the vane to the tray board (bank line) on the intensity and direction of the LSS in SV’s site was found out. Experimentally, an efficient SV setting angle was determined in terms of the formation of steady and intensive LSS along the upstream and the downstream vane face with practically usable direction.

scholarly journals Generation of artificial transverse circulation in an open channel flow by submerged vanes

Vestnik MGSU ◽  
2019 ◽  
pp. 1158-1166 ◽  
Author(s):  
Alexey V. Klovsky ◽  
Dmitry V. Kozlov
Keyword(s):  
Physical Model ◽  
Multiple Regression ◽  
Water Intake ◽  
Theoretical Calculations ◽  
Physical Modelling ◽  
High Water ◽  
Operating Conditions ◽  
Multiple Regression Equation ◽  
Geometric Characteristics ◽  
Transverse Circulation

Abstract Introduction. In this article, we describe a method for sediment control in damless water intake hydraulic units consisting in artificial transverse circulation (ATC) generated by redistributing specific water flow rates in the cross-section of the supply channel. One of the simplest and most effective anti-sediment elements working according to this principle is the submerged vane (SV). The intensity of the ATC formed in the flow depends on the flow regime and the planned-geometric characteristics of the vanes. Available recommendations on the selection of the rational characteristics of SV under the conditions of river damless water intake appear to be contradictory, thus requiring clarification. This study is aimed at examining the interaction between SV and a model flow without water trapping under various planned-geometric characteristics of the vane and experimental hydraulic regimes of its work using a physical model of the errosion-resistant channel. In addition, we set out to assess the effect of essential parameters on the intensity of the ATC generated in the flow. Materials and methods. This research was based on physical modelling hydraulic studies and theoretical calculations. Five hydraulic modes of vane operation with different planned-geometric characteristics were studied using a physical model of the erosion-resistant channel. Multiple regression analysis of the obtained experimental data was carried out. Results. The results of laboratory hydraulic studies on the SV operating conditions are presented. Experimental dependencies characterising the intensity of the ATC generated in the flow are plotted. A multiple regression equation is derived for the amount of the data obtained. Conclusions. It is established that the relative height of the vane and its angle to the side of the flume (coastline) has a significant effect on the intensity of the generated ATC. It is experimentally confirmed for the first time that SV shows little efficiency in high water horizons in terms of in-flow ATC generation.

Cross sections for d-3H neutron interactions with samarium isotopes

2016 ◽  
Vol 104 (8) ◽  
Author(s):  
Junhua Luo ◽  
Chunlei Wu ◽  
Li Jiang ◽  
Long He
Keyword(s):  
Experimental Data ◽  
Neutron Flux ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Nuclear Model ◽  
Activation Technique ◽  
Incident Neutron ◽  
Reaction Threshold ◽  
Talys 1.6 ◽  
The Cross

Abstract:The cross sections for (n,x) reactions on samarium isotopes were measured at (d-T) neutron energies of 13.5 and 14.8 MeV with the activation technique. Samples were activated along with Nb and Al monitor foils to determine the incident neutron flux. Theoretical calculations of excitation functions were performed using the nuclear model codes TALYS-1.6 and EMPIRE-3.2 Malta with default parameters, at neutron energies varying from the reaction threshold to 20 MeV. The results were discussed and compared with experimental data found in the literature. At neutron energies 13.5 and 14.8 MeV, the cross sections of the

Pseudopotential calculations of elastic scattering of electrons by helium atoms in the range 0–20 eV

1990 ◽  
Vol 68 (1) ◽  
pp. 104-110 ◽  
Author(s):  
B. Plenkiewicz ◽  
P. Plenkiewicz ◽  
J.-P. Jay-Gerin
Keyword(s):  
Experimental Data ◽  
Elastic Scattering ◽  
Momentum Transfer ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Incident Electron ◽  
Elastic Electron ◽  
Scattering System ◽  
Helium Atoms ◽  
Pseudopotential Calculations

Our earlier pseudopotential calculations on electrons colliding with argon and krypton are extended to consider the elastic electron–helium scattering system. In this paper, we present detailed results for phase shifts, differential, total, and momentum-transfer cross sections for this system for incident electron energies in the range from 0 to 20 eV. These agree very well with existing experimental data and with other theoretical calculations.

A Comparison of Analytical Predictions With Experimental Measurements of Transmission Error of Misaligned Loaded Gears

1992 ◽  
Author(s):  
Harsh Vinayak ◽  
Donald R. Houser
Keyword(s):  
Experimental Data ◽  
Load Distribution ◽  
Theoretical Calculations ◽  
Data Acquisition System ◽  
Transmission Error ◽  
Test Facility ◽  
Experimental Measurements ◽  
Gear Pair ◽  
Prediction Program ◽  
Dynamic Transmission Error

Abstract This paper deals with the experimental study of dynamic transmission error of a gear pair. Two aspects of the experiment are discussed : 1) design of the test facility and data acquisition system and 2) comparison of transmission error and load distribution with experimental data. Several gears were tested under varying misalignments. A prediction program LDP (Load distribution Program) was used for theoretical calculations of dynamic transmission error.

Development of designing and implementation method of magnetic execution unit of downhole valve for the bottomhole assembly

2020 ◽  
pp. 38-44
Author(s):  
I.Y. Shirali ◽  
◽  
V.Yu. Tsivilitsin ◽  
İ.B. Bondar ◽  
R.A. Hasanov ◽  
...  
Keyword(s):  
Experimental Data ◽  
Theoretical Calculations ◽  
Calculation Methods ◽  
Well Drilling ◽  
Power Characteristics ◽  
Drilling Tools ◽  
Execution Unit ◽  
Implementation Method ◽  
Oil Gas ◽  
Gas Bearing

The structure of two types of magnetic valve is offered and the calculation methods of their pull-in force developed as well. The formulas of calculation of pull-in force in the main area of valves’ power characteristics are obtained. Experimental data are in alignment with theoretical calculations. Power characteristics of offered structures of magnetic valves may be changed in terms of the offered structural execution of magnetic valves. Experimental test of obtained formulas has been carried out. The ways of changing the power characteristics of magnetic valves in accordance with the requirements of certain applications are presented. The structures of magnetic reversing valves for drilling tools used in well drilling in various oil-gas bearing areas of SOCAR have been developed.

COMMENTS ON QCD SUM-RULE CALCULATIONS OF EXCLUSIVE TWO-BODY DECAYS OF CHARMED MESONS

1989 ◽  
Vol 04 (09) ◽  
pp. 877-883 ◽  
Author(s):  
LING-LIE CHAU ◽  
HAI-YANG CHENG
Keyword(s):  
Experimental Data ◽  
Sum Rules ◽  
Theoretical Calculations ◽  
Charmed Mesons ◽  
Qcd Sum Rules ◽  
Generic Structure ◽  
Sum Rule ◽  
Quark Diagram ◽  
Model Independent ◽  
Decays Of Charmed Mesons

Exclusive two-body decay amplitudes of charmed mesons evaluated by Blok and Shifman (BS) using QCD sum rules are analyzed using the model-independent quark-diagram scheme, which helps to pin point the generic structure of the BS calculations, and their difficulties when compared with the experimental data. We also point out what experimental improvements on the data and which new data are most helpful in sharpening these comparisons. Some comments on possible ways of further improving the theoretical calculations are given.

scholarly journals Study of a Conformational Equilibrium of Lisinopril by HPLC, NMR, and DFT

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Sondes Bouabdallah ◽  
Med Thaieb Ben Dhia ◽  
Med Rida Driss
Keyword(s):  
Experimental Data ◽  
Thermodynamic Parameters ◽  
Conformational Equilibrium ◽  
Theoretical Calculations ◽  
Nmr Data ◽  
Major Species ◽  
B3lyp Calculations

The isomerization of lisinopril has been investigated using chromatographic, NMR spectroscopic, and theoretical calculations. The NMR data, particularly the NOEDIFF experiments, show that the major species that was eluted first is thetransform. The proportion was 77% and 23% for thetransandcis, respectively. The thermodynamic parameters (ΔH,ΔS, andΔG) were determined by varying the temperature in the NMR experiments. The interpretations of the experimental data were further supported by DFT/B3LYP calculations.

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