Experimental verification of the quality adaptation mathematical model of the contact network for calculation the vibration frequency

2021 ◽  
pp. 208-215
Author(s):  
A. N. Smerdin ◽  
E. A. Butenko ◽  
A. V. Tarasenko
Keyword(s):  
Mathematical Model ◽  
Vibration Frequency ◽  
Experimental Verification ◽  
Contact Network ◽  
Quality Adaptation

Validation of mathematical model of electrothermal calculation of DC catenary on the basis of scale model

2018 ◽  
Vol 77 (4) ◽  
pp. 222-229 ◽  
Author(s):  
A. V. Paranin ◽  
A. B. Batrashov
Keyword(s):  
Mathematical Model ◽  
Operating Conditions ◽  
Scale Model ◽  
Contact Network ◽  
Scaled Model ◽  
Cross Sectional ◽  
Current Collection ◽  
Topological Features ◽  
Study Results ◽  
Real Physical Process

The article compares the results of calculation of the finite element simulation of current and temperature distribution in the scale model of the DC catenary with the data of laboratory tests. Researches were carried on various versions of the structural design of catenary model, reflecting the topological features of the wire connection, characteristic of the DC contact network. The proportions of the cross-sectional area of the scaled model wires are comparable to each other with the corresponding values for real DC catenary. The article deals with the operating conditions of the catenary model in the modes of transit and current collection. When studying the operation of the scale catenary model in the transit mode, the effect of the structural elements on the current distribution and heating of the wires was obtained. Within the framework of the scale model, theoretical assumptions about the current overload of the supporting cable near the middle anchoring have been confirmed. In the current collection mode, the experimental dependences of the current in the transverse wires of the scale model are obtained from the coordinate of the current collection point. Using the model it was experimentally confirmed that in the section of the contact wire with local wear, not only the temperature rise occurs but also the current redistribution due to the smaller cross section. Thus, the current share in other longitudinal wires of the scale model increases and their temperature rises. Scale and mathematical models are constructed with allowance for laboratory clamps and supporting elements that participate in the removal of heat from the investigated wires. Obtained study results of the scale model allow to draw a conclusion about the adequacy of the mathematical model and its correspondence to the real physical process. These conclusions indicate the possibility of applying mathematical model for calculating real catenary, taking into account the uneven contact wear wire and the armature of the contact network.

scholarly journals OPTIMIZATION OF PROCESS PARAMETERS OF PELLETIZER FOR AGROPYRON SEEDS UNDER VIBRATION FORCE FIELD

2020 ◽  
Vol 60 (1) ◽  
pp. 147-154 ◽  
Author(s):  
Zhanfeng Hou ◽  
Yi Qiu ◽  
Zhi Chen ◽  
Haiyang Liu ◽  
Fang Guo ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Vibration Frequency ◽  
Tilt Angle ◽  
Seed Rate ◽  
Rotating Speed ◽  
Experimental Platform ◽  
Single Seed ◽  
The Poor ◽  
Optimization Of Process Parameters

In order to solve the poor pelleting quality of Agropyron seeds, this paper designs a novel pelleting experimental platform. A regression mathematical model of pelleting qualified rate and single seed rate was established and analysed by variance. The results showed that vibration had significant effect on pelleting quality. The order of influence is as follows: rotating speed>vibration frequency> tilt angle of coater. When the speed is 41.7 r/min, the vibration frequency is 20.28 Hz, and the tilt angle is 34.89 °, the pelleting qualified rate and the single seed rate are the highest, 83.1% and 94.9% respectively

Математическое описание и анализ сигнала виброиндукционного преобразователя при воздействии нормальной составляющей магнитных потоков рассеяния над дефектным участком

2021 ◽  
Vol 7 ◽  
pp. 19-27
Author(s):  
Ю.Л. Николаев ◽  
П.Н. Шкатов ◽  
Э.Ф. Ахметшина ◽  
А.А. Саморуков
Keyword(s):  
Magnetic Field ◽  
Mathematical Model ◽  
Initial Data ◽  
Vibration Frequency ◽  
Magnetic Field Intensity ◽  
Theoretical Research ◽  
Leakage Magnetic Field ◽  
Induction Transducer ◽  
Experimental Researches ◽  
Defective Area

Theoretical and experimental researches of vibration-induction transducer (VIT) outlet signal formed during exposure to normal leakage magnetic field intensity component Hn over the defective area were carried out. Theoretical research is based on an assumption that VIT signal is a trigonometric series that is limited by first five harmonics. As initial data for mathematical model creation, well-known conformities for Hn distribution over the defective area were used. Based on acquired mathematical model conformities of VIT signal harmonical composition permutation during its movement over the defective area with varying amplitudes and vibration frequency were found. Theoretical research results were proven experimentally. Moreover, additional possibilities of this way of magnetic testing are shown in comparison with conventional ones.

scholarly journals Pneumatic Adaptive Absorber: Mathematical Modelling with Experimental Verification

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Grzegorz Mikułowski ◽  
Rafał Wiszowaty
Keyword(s):  
Mathematical Model ◽  
Mathematical Modelling ◽  
Experimental Verification ◽  
Load Capacity ◽  
Mechanical Energy ◽  
Specific Situation ◽  
Engineering Structures ◽  
Piston Cylinder ◽  
Proposed Model ◽  
Energy Absorbers

Many of mechanical energy absorbers utilized in engineering structures are hydraulic dampers, since they are simple and highly efficient and have favourable volume to load capacity ratio. However, there exist fields of applications where a threat of toxic contamination with the hydraulic fluid contents must be avoided, for example, food or pharmacy industries. A solution here can be a Pneumatic Adaptive Absorber (PAA), which is characterized by a high dissipation efficiency and an inactive medium. In order to properly analyse the characteristics of a PAA, an adequate mathematical model is required. This paper proposes a concept for mathematical modelling of a PAA with experimental verification. The PAA is considered as a piston-cylinder device with a controllable valve incorporated inside the piston. The objective of this paper is to describe a thermodynamic model of a double chamber cylinder with gas migration between the inner volumes of the device. The specific situation considered here is that the process cannot be defined as polytropic, characterized by constant in time thermodynamic coefficients. Instead, the coefficients of the proposed model are updated during the analysis. The results of the experimental research reveal that the proposed mathematical model is able to accurately reflect the physical behaviour of the fabricated demonstrator of the shock absorber.

A Hysteresis Restoring Force Model of Disc-Shaped Metal Rubber Isolation Component

2012 ◽  
Vol 271-272 ◽  
pp. 186-189 ◽  
Author(s):  
Feng Li Cao ◽  
Hong Bai Bai ◽  
Zhong Bo He ◽  
Guo Quan Ren
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Experimental Verification ◽  
Vibration Isolation ◽  
Practical Significance ◽  
Force Model ◽  
Stiffness Coefficient ◽  
Restoring Force ◽  
Restoring Force Model ◽  
Metal Rubber

Dynamic load experiments of the disc-shaped metal rubber isolation component are performed. Through analyzing variation law of the parameters with amplitude and frequency, which are stiffness coefficient, damping coefficient and damping component factor, the hysteresis restoring force model which is able to fully reveal the dynamic characteristics of the component is established. The experimental verification results show that the theoretic calculations are consistent with the experimental data, which verifies the practicability and effectiveness of mathematical model and parameter identification. It has important practical significance for design of vibration isolation component with different requirements.

scholarly journals Modeling of Pressure Drop During Refrigerant Condensation in Pipe Minichannels

2017 ◽  
Vol 38 (4) ◽  
pp. 15-28 ◽  
Author(s):  
Małgorzata Sikora ◽  
Tadeusz Bohdal
Keyword(s):  
Mathematical Model ◽  
Pressure Drop ◽  
Computer Modeling ◽  
Experimental Verification ◽  
Flow Resistance ◽  
Experimental Results ◽  
Experimental Investigations ◽  
Flow Conditions ◽  
Conservation Equations ◽  
Mathematical And Computer Modeling

Abstract Investigations of refrigerant condensation in pipe minichannels are very challenging and complicated issue. Due to the multitude of influences very important is mathematical and computer modeling. Its allows for performing calculations for many different refrigerants under different flow conditions. A large number of experimental results published in the literature allows for experimental verification of correctness of the models. In this work is presented a mathematical model for calculation of flow resistance during condensation of refrigerants in the pipe minichannel. The model was developed in environment based on conservation equations. The results of calculations were verified by authors own experimental investigations results.

Sign in / Sign up

Export Citation Format

Share Document