Improvement of vibration frequency and energy efficiency in the uniaxial electro-hydraulic shaking tables for sinusoidal vibration waveform

Energy ◽  
2021 ◽  
Vol 218 ◽  
pp. 119477
Author(s):  
He Wang ◽  
Zhen Chen ◽  
Jiahai Huang
Keyword(s):  
Energy Efficiency ◽  
Vibration Frequency ◽  
Sinusoidal Vibration

scholarly journals Vibration Compensation of the Frequency-Scanning-Interferometry-Based Absolute Ranging System

2019 ◽  
Vol 9 (1) ◽  
pp. 147 ◽  
Author(s):  
Fu-Min Zhang ◽  
Ya-Ting Li ◽  
Hao Pan ◽  
Chun-Zhao Shi ◽  
Xing-Hua Qu
Keyword(s):  
Standard Deviation ◽  
Vibration Frequency ◽  
Phase Modulation ◽  
Vibration Velocity ◽  
Sinusoidal Vibration ◽  
Vibration Effect ◽  
Frequency Scanning ◽  
Blind Area ◽  
Frequency Scanning Interferometry ◽  
Vibration Compensation

The frequency-scanning-interferometry-based (FSI-based) absolute ranging technology is a type of ranging technology possessing a high precision and no ranging blind area, so it can be used for non-cooperative targets. However, due to a tiny movement of a target, the Doppler shift and the phase modulation are introduced into the beat signal which results in ranging accuracy decrease. In order to solve this problem, first the model of vibration effect is established, and then the beat signals of two adjacent scanning periods are processed to produce a signal that is immune to vibration. The proposed method is verified by the experiments, and the experimental results show that the effect of vibration compensation is better for the target with a lower vibration velocity and at a lower vibration frequency (lower than 6 Hz). When the target is subjected to a sinusoidal vibration with an amplitude of 10 μm at a frequency of 1 Hz, by using the proposed method the standard deviation is reduced from 775 to 12 μm. Moreover, in the natural environment, by using vibration compensation the standard deviation is reduced from 289 to 11 μm.

Analytical solution to orifice design in a rotary valve controlled electro-hydraulic vibration exciter for high-frequency sinusoidal vibration waveform

2019 ◽  
Vol 233 (5) ◽  
pp. 1098-1108
Author(s):  
He Wang ◽  
Chengwen Wang ◽  
Long Quan ◽  
Guofang Gong ◽  
Wenjing Li
Keyword(s):  
Analytical Solution ◽  
Vibration Frequency ◽  
Axial Length ◽  
High Frequency ◽  
Harmonic Distortion ◽  
Total Harmonic Distortion ◽  
Design Solution ◽  
Vibration Exciter ◽  
Rotary Valve ◽  
Sinusoidal Vibration

The present study is focused on a novel method for the acquisition of high-frequency sinusoidal vibration waveform with electro-hydraulic vibration exciter. A rotary valve controlled electro-hydraulic vibration exciter is proposed to make it easier to obtain high vibration frequency than the conventional servo valve controlled counterpart. Three common used offices are taken into consideration: rectangular orifice, triangular orifice, and semicircular orifice. Analytical solution to orifice design of shape and axial length is suggested for the accurate control of vibration waveform. Harmonic theory borrowed from electronic technology is used as an evaluation index for the shape of vibration waveform. The orifice shape design decision is made according to the total harmonic distortion of vibration waveform. The nonlinear differential equation which models vibration waveform is established. The orifice axial length is designed according to the supply pressure, vibration frequency, and amplitude. Both theoretical and experimental results show that rectangular orifice is desirable for high-frequency sinusoidal vibration waveforms. With the orifice design solution, the proposed vibration exciter can output the vibration waveform with total harmonic distortion of less than 1% as compared with sinusoidal waveform and maximum error of 5% as compared with experimental value at vibration frequency of higher than 100 Hz, and greatly extend the frequency bandwidth when sinusoidal vibration waveform is required.

A rotary valve controlled electro-hydraulic vibration exciter

2016 ◽  
Vol 230 (19) ◽  
pp. 3397-3407 ◽  
Author(s):  
He Wang ◽  
Guofang Gong ◽  
Hongbin Zhou ◽  
Wei Wang ◽  
Yi Liu
Keyword(s):  
Vibration Frequency ◽  
Harmonic Distortion ◽  
Response Speed ◽  
Slide Valve ◽  
Vibration Exciter ◽  
Rotary Valve ◽  
Sinusoidal Vibration ◽  
Servo Valve ◽  
Electric System ◽  
Supply Pressure

When sinusoidal vibration waveform is required, the frequency bandwidth of conventional electro-hydraulic vibration exciter controlled by servo valve is always limited to a rather narrow range due to the limits of slide valve structure and response speed, and no parameter is available for defining and evaluating the waveform quality. In this paper, a novel electro-hydraulic vibration exciter controlled by electromotor driven rotary valve is proposed to significantly extend the frequency range compared to the conventional servo valve controlled counterpart. Total harmonic distortion (THD) theory which is usually used to cope with voltage and current in electric system is borrowed to evaluate the quality of theoretical and experimental vibration waveforms at different supply pressures and vibration frequencies, quantitatively and qualitatively. The results show that the waveform quality is mainly influenced by the 3rd harmonic resonance. The proposed vibration exciter can output sinusoidal waveform with THD less than 5% at the vibration frequency higher than 70 Hz. In this frequency domain, the supply pressure has an extremely low impact on the THD of the waveform. The amplitude of the waveform can be adjusted by changing the supply pressure with almost no effect to the waveform quality at a certain vibration frequency.

scholarly journals Analysis on vibration for a high-frequency electro-hydraulic cleaning system controlled by improved two-dimensional rotary valve

2018 ◽  
Vol 10 (12) ◽  
pp. 168781401881141
Author(s):  
Xiancheng Ji ◽  
Yan Ren ◽  
Hesheng Tang
Keyword(s):  
Vibration Frequency ◽  
High Frequency ◽  
Functional Materials ◽  
Pressure Amplitude ◽  
Two Dimensional ◽  
Rotary Valve ◽  
Sinusoidal Vibration ◽  
High Frequency Vibration ◽  
Cleaning System ◽  
Sinusoidal Waveform

Conventional high-frequency cleaners utilize functional materials (e.g. piezoelectric ceramics, magnetostrictive materials) excited by electrical signals to realize high-frequency vibration, even ultrasonic vibration. However, it is difficult to produce a large force without sacrificing bandwidth because of the physical characteristics of materials themselves. Therefore, a high-frequency high-power cleaner driven by electro-hydraulic excitation is proposed. Only a few studies are performed on electro-hydraulic cleaners, owing to the limitation of frequency bandwidth of the electro-hydraulic system. Thus, a rotary valve named two-dimensional valve is improved and adopted to improve high-frequency performances of the electro-hydraulic cleaner. In this article, a two-dimensional rotary valve with a linear variable differential transformer is designed, and the vibration characteristics of the electro-hydraulic cleaner controlled by this valve are discussed in detail, especially vibration acceleration, vibration frequency, and pressure amplitude. A prototype of the electro-hydraulic cleaner is modeled and both a theoretical analysis and experimental investigation are carried out. Theoretical and experimental results indicate that the electro-hydraulic cleaning system outputs sinusoidal vibration waveforms, especially in a high-frequency domain, which could realize the vibration frequency of 2669 Hz. The measured waves at different frequencies (below the resonant frequency) demonstrate different distortions compared with the sinusoidal waveform. These distortions can be associated with the hydraulic resonance. At hydraulic resonance (1903 Hz), the amplitude is increased significantly and the vibration waveform becomes more pronounced. Nevertheless, the study does provide an access to the electro-hydraulic high-frequency vibration applied in cleaning or other engineering cases.

Study of Rheological Behavior of Calcium Carbonate Filled Polypropylene in Dynamic Extrusion

2014 ◽  
Vol 1053 ◽  
pp. 231-234 ◽  
Author(s):  
Quan Wang ◽  
Xiao Sun ◽  
Zheng Huan Wu
Keyword(s):  
Calcium Carbonate ◽  
Vibration Frequency ◽  
Rheological Behavior ◽  
Apparent Viscosity ◽  
Polymer Melt ◽  
Measuring Apparatus ◽  
Melt Rheology ◽  
Sinusoidal Vibration ◽  
Dynamic Extrusion ◽  
Vibration Parameters

A novel rheological measuring apparatus was designed, which introduced an additional sinusoidal vibration in parallel on the extruding direction of polymer melt in this paper. Melt rheology of polypropylene filled CaCO3 particles in various amounts of filler (i.e. with 3 and 20 wt%) during capillary melt-extrusion were investigated respectively. The effects of vibration parameters on rheological behaviors were studied. Compared with the steady extrusion, the apparent viscosity of filled system decreased remarkably with the increase of vibration frequency and amplitude. The apparent viscosity reached to the minimum value as vibration frequency was about 8 Hz. When the filled percentage of CaCO3 was low, the response of apparent viscosity will be more distinct with the increasing vibration parameters.

A novel method for high-frequency non-sinusoidal vibration waveforms with uniaxial electro-hydraulic shaking table based on Fourier series

2020 ◽  
pp. 107754632096171
Author(s):  
He Wang ◽  
Zhen Chen ◽  
Jiahai Huang
Keyword(s):  
Fourier Series ◽  
Vibration Frequency ◽  
High Frequency ◽  
Narrow Range ◽  
Harmonic Distortion ◽  
Shaking Table ◽  
Rotary Valve ◽  
Sinusoidal Vibration ◽  
Supply Pressure ◽  
Novel Method

In this article, a rotary valve is developed to obtain accurate high-frequency sinusoidal vibration waveforms. Then, a uniaxial electro-hydraulic shaking table controlled by a set of parallel rotary valves is constructed, which can superpose the sinusoidal vibration waveforms. The non-sinusoidal vibration waveforms including triangular vibration waveform, rectangular vibration waveform, sawtooth vibration waveform and trapezoidal vibration waveform are generated by adjusting the spool rotation speed based on the Fourier series. The results show that with one rotary valve, the uniaxial electro-hydraulic shaking table can output accurate high-frequency sinusoidal vibration waveforms and the total harmonic distortion is less than 1% at high vibration frequency. Compared with the standard vibration waveform, the error of the generated vibration waveform is very small. For the rectangular vibration waveform and sawtooth vibration waveform, the error is less than 6%, and for the triangular vibration waveform and trapezoidal vibration waveform, the error is less than 3%. The impacts of the working conditions on the error of the generated vibration waveform are very small. The proposed method for the accurate high-frequency non-sinusoidal vibration waveform is very effective and can be applied in high vibration frequency and different load masses. With the increase of the supply pressure, the amplitude of the generated vibration waveforms increases, while the error changes in a rather narrow range. The amplitude can be adjusted by changing the supply pressure with almost no effect on the accuracy of the vibration waveform.

Drying and heating of scrap metal at steelmaking: industrial safety, economics, ecology

2020 ◽  
Vol 76 (12) ◽  
pp. 1353-1258
Author(s):  
V. A. Spirin ◽  
V. E. Nikol’skii ◽  
D. V. Vokhmintsev ◽  
A. A. Moiseev ◽  
P. G. Smirnov ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
High Efficiency ◽  
Steel Production ◽  
Scrap Metal ◽  
Industrial Safety ◽  
Technical Solution ◽  
Metal Charge ◽  
Basic Task ◽  
Scrap Heating ◽  
Winter Time

At steel production based on scrap metal utilization, the scrap heating before charging into a melting facility is an important way of energy efficiency increase and ecological parameters improving. In winter time scrap metal charging with ice inclusions into a metal melt can result in a considerable damage of equipment and even accidents. Therefore, scrap preliminary drying is necessary to provide industrial safety. It was shown, that in countries with warm and low-snow climate with no risk of scrap metal icing up during its transportation and storing in the open air, the basic task being solved at the scrap drying is an increase of energy efficiency of steelmaking. InRussiathe scrap metal drying first of all provides the safety of the process and next - energy saving. Existing technologies of scrap metal drying and heating considered, as well as advantages and drawbacks of technical solutions used at Russian steel plants. In winter time during scrap metal heating at conveyers (Consteel process) hot gases penetrate not effectively into its mass, the heat is not enough for evaporation of wetness in the metal charge. At scrap heating by the furnace gases, a problem of dioxines emissions elimination arises. Application of shaft heaters results in high efficiency of scrap heating. However, under conditions of Russian winter the upper scrap layers are not always heated higher 0 °С and after getting into a furnace bath the upper scrap layers cause periodical vapor explosions. The shaft heaters create optimal conditions for dioxines formation, which emit into atmosphere. It was shown, that accounting Russian economic and nature conditions, the metal charge drying and heating in modified charging buckets by the heat of burnt natural gas or other additional fuel is optimal. The proposed technical solution enables to burnt off organic impurities ecologically safely, to melt down ice, to evaporate the wetness in the scrap as well as to heat the charge as enough as the charging logistics enables it. The method was implemented at several Russian steel plants. Technical and economical indices of scrap metal drying in buckets under conditions of EAF-based shop, containing two furnaces ДСП-100, presented.

Perspectives and Regulation of the Russian Market for Project-based Transactions under the Kyoto Protocol

2008 ◽  
pp. 108-125
Author(s):  
K. Zavodov
Keyword(s):  
Energy Efficiency ◽  
Market Mechanism ◽  
Point Of View ◽  
Market Regulation ◽  
Foreign Investments ◽  
Russian Market ◽  
Increase Energy Efficiency ◽  
New Form ◽  
Contract Structure ◽  
Carbon Fund

Project-based transactions (PBTs) are a market mechanism of attracting foreign investments in order to abate greenhouse gas emissions and increase energy efficiency of the country’s enterprises. The article provides a classification and analyzes advantages and drawbacks of PBTs from the point of view of a host country. The main trends and factors determining the dynamics of the PBT market are described. Given that Russia currently lags behind the leaders of the PBT market, an incorporation of a state carbon fund is put forward with an aim of channelling PBTs through it. This paper proposes a form of PBT market regulation by incorporating an option mechanism into the contract structure of a transaction. A comparison of the new form of regulation with the tools that are currently in use in Russia and other countries demonstrates its greater economic efficiency under uncertainty.

Sign in / Sign up

Export Citation Format

Share Document