Experimental research of geometrical parameters influencing factor on fuel assembly mixing characteristics

2021 ◽  
Vol 164 ◽  
pp. 108634
Author(s):  
Cheng Cheng ◽  
Qianhua Su ◽  
Donghua Lu ◽  
Xiaohang Wu
Keyword(s):  
Fuel Assembly ◽  
Experimental Research ◽  
Influencing Factor ◽  
Geometrical Parameters ◽  
Mixing Characteristics

An Experimental Study of Thermohydraulic Processes in the Model of a Fuel Assembly with Micro Fuel Elements

Vestnik MEI ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 19-25
Author(s):  
Aleksandr V. Zakharenkov ◽  
◽  
Ivan A. Tupotilov ◽  
Kirill V. Zhuravlev ◽  
◽  
...  
Keyword(s):  
Fuel Assembly ◽  
Test Section ◽  
Pressure Loss ◽  
Experimental Studies ◽  
Internal Heat ◽  
Coolant Temperature ◽  
Geometrical Parameters ◽  
Pebble Bed ◽  
Flow Friction ◽  
Fuel Elements

The test section design of the TVS-MEI experimental setup intended for studying the hydrodynamics and heat transfer in a fuel assembly with micro fuel elements is developed, and the setup hydraulic circuit is modernized. The setup process characteristics correspond to the operational parameters of VVER-1000 reactor plants (a pressure up to 16 MPa and coolant temperature up to 350°C). The internal heat release in the bed of metal pebbles is obtained by high-frequency induction heating. A technology for compacting the test section made of high-strength alundum ceramics and a special clamping device for holding the bed were developed. The fuel assemblies with micro fuel elements have the outer geometrical parameters fully identical with those of the conventional assemblies with fuel rods. A technology for installing, wiring, and sealing thermocouples in the test section has been developed. Experimental studies aimed at determining the pressure loss and flow friction coefficient for a cylindrical pebble bed were carried with the following coolant operating parameters: P = (2--7) MPa and G = (0.05--0.5) kg/s. In processing the obtained experimental results, the dependences of pressure loss on the coolant mass velocity and the pebble bed flow friction on the Reynolds number were identified and plotted. The first experimental data on the temperature distribution in the pebble bed are obtained. The main objective of the experiments was to determine the possibility of heating the considered test section by using the chosen method.

Sensibility Analysis of Mechanical and Geometrical Parameters On Soil Slope Stability

2011 ◽  
Vol 268-270 ◽  
pp. 1712-1716 ◽  
Author(s):  
Xu Sheng Yang
Keyword(s):  
Slope Stability ◽  
Influencing Factor ◽  
Slope Angle ◽  
Friction Angle ◽  
Grey System Theory ◽  
Stability Factor ◽  
Geometrical Parameters ◽  
Grey System ◽  
Dilatancy Angle ◽  
Grey Correlation Analysis

Based on the FLAC2D finite difference software, We can use strength reduction theory to gained the stability factor of the 48 soil slopes under the different conditions, Grey Correlation Analysis Method of the Grey System Theory is employed to analyze the sensitivities of factor influencing slope stability. The matrix of correlation data is setup, the elements of which are transformed to dimensionless parameters. The grey correlative factors and grey correlative degrees which respect to the influencing factor and the slope stability factor are computed, and the sensible factors influence slope stability are decided. The results show that the cohesion of the soil. The density and the internal friction angle are the most sensitive factors to the slope stability, and the dilatancy angle, slope angle and the slope height are taken second place, which provide a reference to the reasonably and effectively design of the actual slope works.

scholarly journals RESEARCH INTO RAIL SIDE WEARING ON CURVES

Transport ◽  
2003 ◽  
Vol 18 (3) ◽  
pp. 124-129 ◽  
Author(s):  
Inesa Povilaitienė ◽  
Igoris Podagėlis
Keyword(s):  
Experimental Research ◽  
Experimental Results ◽  
Geometrical Parameters ◽  
Dynamic Changes ◽  
Rail Track ◽  
Railway Line ◽  
Factors Influencing ◽  
Measurement Results

Factors influencing rail side wearing in the curves are described in the article. All of them are divided into uncontrolled, partially controlled and controlled. An experiment was carried out on Lithuanian railway line curves. The experiment proceeding conditions and the obtained results are presented. The object of the experimental research is 19 curves. The investigations of dynamic changes in rail wearing and in rail track geometrical parameters on curves were being carried out for one and a half year. The experimental results, associated with the railway gauge influence on rail wearing on curves are analyzed more precisely. Measurement results are described using mathematical dependences. According to the dependences it is possible to estimate the influence of gauge on rail side wearing on curves.

scholarly journals Experimental Research on the Impact of Thin-Wall Ratio and the Fillet Radius of Forming Roller on the Limiting Spinning Ratio of AMS 5504 Sheets

2017 ◽  
Vol 62 (4) ◽  
pp. 2261-2266
Author(s):  
S. Kut ◽  
F. Stachowicz ◽  
G. Ryzińska ◽  
T. Mrugała
Keyword(s):  
Experimental Research ◽  
Vertical Axis ◽  
Experimental Investigations ◽  
Geometrical Parameters ◽  
Thin Wall ◽  
Fillet Radius ◽  
Spinning Process ◽  
Metal Spinning ◽  
The Impact ◽  
Negative Phenomena

AbstractResults of experimental investigations of metal spinning process of AMS 5504 sheets. cylindrical drawpieces with use of discs-shaped sheet with various diameter and thickness were shown in this work. Tests were performed on two roller metal spinning machine of a vertical axis Leifeld SFC 800 V500.The main objective of the study was to determine the dependence between limiting spinning coefficient, thin wall ratio coefficient and the fillet radius of forming rollers. To realize this aim required the development of an original methodology and experimental research plan. Determined relationship takes into account the occurrence of negative phenomena in the process of spinning such as wrinkling or cracking of material.Due to the possibility of prediction of these negative phenomena, determined relationship is used in the design of a metal spinning processes. On the basis on determined relationship can be done a practical assessment of the possibility of shaping with certain geometrical parameters by spinning. Obtained results were shown graphically on the diagrams and their analysis was carried.

scholarly journals METHODS OF EXPERIMENTAL RESEARCH JUSTIFICATION OF MINIMUM GEOMETRIC PARAMETERS OF GRAVEL BACKFILL IN THE OIL RECEIVER OF THE TRANSFORMER SUBSTATION

2021 ◽  
Vol 4 (164) ◽  
pp. 158-165
Author(s):  
R. Klymas ◽  
V. Nizhnyk ◽  
Ya. Ballo ◽  
D. Khromenkov ◽  
Yu. Gulyk ◽  
...  
Keyword(s):  
Experimental Research ◽  
Experimental Studies ◽  
Flash Point ◽  
Geometric Parameters ◽  
Transformer Oil ◽  
Design Parameters ◽  
Geometrical Parameters ◽  
Fire Control ◽  
Transformer Substation ◽  
Fire Barrier

Transformer is one of the most fire-hazardous types of equipment at power substations. In case of emergency operation or damage to the integrity of the case they can cause a fire. Statistics on fires show that 50 % of fires in the energy sector are transformer equipment; as a rule, such fires are accompanied by an emergency spill of oil from the transformer and its ignition. Existing approaches to limiting the spread of fire during accidents at oil-filled transformer substations are insufficient and economically costly to minimize the consequences of burning transformer oil spills. At the same time, a number of design parameters have been identified that negatively affect the effectiveness of fire control. In particular, the Rules for Arrangement of Electrical Installations provide for the provision of electrical substations with oil receivers which is covered with gravel, and the latter is constantly polluted due to environmental influences which impairs its capacity and cooling capacity. The design and geometrical parameters of oil receivers with oil removal by oil drains defined in Rules for Arrangement of Electrical Installations can be a subject of scientific researches for their improvement. The purpose of this article is to determine the main provisions of the methodology of experimental studies to substantiate the minimum geometric parameters of gravel backfill in the oil receiver of the transformer substation. The ultimate goal of the study is to identify patterns of changes in the temperature of transformer oil from the parameters and characteristics of the oil pan, which should perform the function of a fire barrier and cooling the oil below the flash point. The essence of the method of experimental research is to identify patterns of reduction of the combustion temperature of transformer oil to a temperature below the flash point depending on the geometric parameters of the gravel backfill during oil draining into the emergency tank (oil tank). The developed technique allows to determine changes in the temperature of transformer oil from the geometric parameters of the oil pan, which should perform the function of a fire barrier and cooling the oil below the flash point.

Experimental research on the compressed joints with different geometrical parameters

2017 ◽  
Vol 233 (1) ◽  
pp. 174-181 ◽  
Author(s):  
Chao Chen ◽  
Shuqin Fan ◽  
Xiaolan Han ◽  
Shengdun Zhao ◽  
Minchao Cui ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Aluminium Alloy ◽  
Experimental Research ◽  
Metal Flow ◽  
Geometrical Parameters ◽  
Automotive Body ◽  
Shearing Strength ◽  
Mechanical Clinching ◽  
Neck Thickness ◽  
Neck Fracture

In recent years, mechanical clinching has been widely used to join aluminium alloy sheets to build the automotive body. The high protrusion on the joint may limit the use of the mechanical clinching in the visible places. In order to get a lower protrusion, a compressing method was investigated in this work. Clinched joints with different geometrical parameters were used to conduct the experiments. AL5052 was taken as the material of the sheets. The protrusion of the clinched joint was compressed by two flat dies. A rivet placed in the pit of the clinched joint was used to control the metal flow in the compressing process. The top die moved downward to compress the protrusion, and the bottom die was fixed. The study shows that the tension-shearing strength and cross-tensile strength can be increased by the compressing method. The compressing method can increase the tension-shearing strength and cross-tensile strength by increasing the neck thickness. The compressed joint has larger neck thickness and lower protrusion than the clinched joint. Neck fracture mode is the main failure mode of the joints. The energy absorption can also be increased after the compressing process.

Statistical Impact of Manufacturing Tolerances on Axial Gaps Between Vane Segments and the Rotor of Axial Flow Turbo-Compressors

2013 ◽  
Author(s):  
Stefan Weihard ◽  
Andreas Hupfer ◽  
Hans-Peter Kau
Keyword(s):  
Probability Distribution ◽  
Simulation Model ◽  
Influencing Factor ◽  
Axial Flow ◽  
Design Parameters ◽  
Geometrical Parameters ◽  
3D Analysis ◽  
Tolerance Interval ◽  
The Impact ◽  
Gap Values

Geometrical deviations arising from the manufacturing process significantly influence the axial gaps between rotating and nonrotating parts. To optimize axial gaps and thus reduce the overall length and weight of the compressor, it is essential to take the statistical nature of these deviations into account. The focus of this paper is to identify complex three-dimensional effects caused by geometrical uncertainties. The results can be then used to define an appropriate level of detail for the simulation model in order to accurately predict the probability distribution of axial gaps. In the simulation model the parts are assembled according to defined mechanical constraints and the paper presents mathematical models regarding this. A simplified 2D model of a sectional view and a detailed 3D model are implemented and investigated. A 2D tolerance analysis shows that a statistical gap tolerance can be defined based on geometrical parameters. It must be assumed that a certain percentage of all gap values will fall below the lower specification limit for this tolerance interval. A detailed 3D analysis, however, results in a change in the probability distribution of the gap values compared to the simplified 2D analysis. In addition to the standard deviation, the mean value of the gap is reduced significantly. Therefore, a simplified 2D approach may yield invalid results. What this effect is will depend on the configuration. One influencing factor is the number of vane segments in the compressor stage. A sensitivity analysis is presented which identifies and quantifies the impact of such important design parameters.

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