• Title, Summary, Keyword: Permittivity

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Measurement Of The Engine Oil Relative Dielectric Constant With Respect To Capacitive Prove Dimension (정전용량 프로브 크기에 대한 엔진오일 상대 유전율 측정)

  • Kim, Ki-Hoon;Kim, Young-Ju
    • Tribology and Lubricants
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    • v.27 no.4
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    • pp.209-212
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    • 2011
  • The capacitive application(prove) can be used to measure the complex permittivity of dielectric material of various thickness and cross section. This paper presents that we designed the analysis system of engine oil permittivity to know the relation between the engine oil deterioration and the prove dimension. Each of the dimension of capacitive prove is changed and then electric capacity is measured by LCR {Inductance(L), Capacitance (C), and Resistance (R)} meter. The engine oil permittivity has extracted in the prove measurement. As the additional research, this paper suggest the best of the prove dimension for the permittivity measurement.

A Permittivity Measurement of Dielectric Slabs Using a Parallel Plate Waveguide (평행판 도파관을 이용한 유전율 측정 방법)

  • Cho, Gyo-Yeong;Park, Wee-Sang
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.2
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    • pp.199-203
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    • 2012
  • This paper introduces a simple new procedure approach to determine the permittivity of dielectric slabs. The method uses a parallel plate waveguide which supports a TEM mode. The presence of the dielectric slab placed at the bottom of the waveguide makes the speed of the TEM wave slower. The relationship between the change of the speed and the permittivity of the dielectric slab allows the determination of the permittivity. The relationship is analyzed electromagnetically, and the results of measurements are in good agreement with the analysis.

Complex Permittivity of Foam Materials at X-Band (X-대역에서의 Foam 재료의 복소 유전율)

  • 방재훈;안병철
    • Proceedings of the IEEK Conference
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    • pp.72-75
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    • 2000
  • This paper investigates the complex permittivity of foam materials using the rectangular waveguide. The transmission coefficients of materials inserted in the waveguide are measured with a network analyzer and calculated from the equivalent transmission line model. We use the trial and error method in the acquisition of the complex permittivity.

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Analysis of the Grounding Impedance of a Ground Rod Considering the Frequency-Dependent Resistivity and Relative Permittivity of Soil (토양의 저항률 및 비유전율의 주파수의존성을 고려한 접지봉의 접지임피던스의 해석)

  • Ahn, Chang-Hwan;Choi, Jong-Hyuk;Lee, Bok-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.1
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    • pp.54-60
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    • 2012
  • When the transient current with high frequency components such as lightning surges are injected the grounding electrodes, the performance of grounding electrodes should be evaluated as grounding impedance. It is restricted to analyze the grounding impedance by measurement approach since the grounding impedance is very different with the shape and size of grounding electrodes, resistivity and relative permittivity of soil and the frequency component of the injected current. So a variety of simulation approaches have been developed. Typically, the soil resistivity measured with low frequency and relative permittivity between 1 and 80 are used for simulation of the grounding impedance. However, the resistivity and relative permittivity of soil are changed with frequency of injected current. In this paper, the frequency-dependent resistivity and relative permittivity of soil are measured and these parameters are reflected in the simulation of the grounding impedance of a ground rod. The simulated results are compared with the measured results. As a result, the simulated results with frequency-dependent soil parameters show capacitive aspect like measured results in the frequency of lower than 100[kHz] and they are more consistent with the measured results in wide frequency range.

Electrical Characteristics against Frequency and Concentration of Contaminated Soils by Mercury and Arsenic (수은과 비소로 오염된 시료의 측정주파수와 농도 변화에 따른 전기적 특성)

  • Son, Young-Hwan;Bong, Tae-Ho;Chang, Pyoung-Wuck
    • Journal of The Korean Society of Agricultural Engineers
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    • v.50 no.6
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    • pp.15-24
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    • 2008
  • In general, ground pollution can be classified with soil pollution and underground water pollution. And ground pollution contaminates the land with garbage dumps and other harmful waste products as heavy metals that can also eventually enter our water supply. This study was conducted to define a characteristics of the electrical resistivity and the permittivity of weathered soil that was contaminated with heavy metals as Mercury and Arsenic. It is not easy whether contamination of soil as subsurface contamination is decided or not and at an early stage especially do that. Therefore the electrical resistivity and the permittivity were used to make up for this defects. These methods are more economical and more effective than the existing methods. And variation of the electrical resistivity and the permittivity values were found against the change of concentration of Mercury and Arsenic aqueous solutions and measuring frequency. These analyzed results indicate that the electrical resistivity and the permittivity tend to decrease against increasing measuring frequency. The electrical resistivity and the permittivity are also found to show the function of frequency.

Error Analysis for Microwave Permittivity Measurement using Post Resonator Method (Post Resonator 방법에 의한 마이크로파 유전율 측정에서의 오차 분석)

  • Cho, Mun-Seong;Lim, Donggun;Park, Jae-Hwan;Park, Jae-Gwan
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.3
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    • pp.43-48
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    • 2012
  • Errors of relative permittivity calculation caused by the variation of sample aspect ratio (diameter/height) and measuring geometry were analyzed by computer simulation and measurement. Firstly, the $S_{21}$ spectrum of the sample (permittivity 38) was simulated in the post resonator measuring apparatus by HFSS simulation. Then, the relative permittivity was calculated from the $TE_{011}$ mode resonant frequency. The relative permittivity varied by ca. 0.3% with sample aspect ratio variation (D/H=0.8~1.6). The relative permittivity varied by ca. 1~10% when the 1~10% of air-gap was introduced in between the dielectric disk and upper conductor. All the simulation results showed consistent tendency with real measurement.

Relative Permittivity of Damaged Concrete Bridge Deck According to the Weather Conditions : A Case Study (기상조건에 따른 손상 교량 바닥판의 상대유전율 변화 고찰)

  • Rhee, Ji-Young;Choi, Jae-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.209-215
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    • 2017
  • Ground Penetrating Radar (GPR) was applied to an evaluation of the concrete condition of bridge decks with asphalt concrete. Deterioration was considered to have occurred when the relative permittivity of a concrete-faced asphalt concrete overlay showed more than 12. The relative permittivity of concrete varied considerably with the levels of porosity and water. In this study, GPR tests were carried out to determine the influence of weather and concrete condition on the relative permittivity for the research subject of an overlaid concrete bridge deck in public service. According to the test results, if bridge decks are in good condition, the relative permittivity of the top concrete of a bridge deck exhibited a normal distribution. After the deck concrete deteriorated, the relative permittivity varied with the amount of penetrated water according to the weather condition and deteriorated status of deck concrete.

A Study on the Dielectric Properties of Epoxy Composites with Frequency Variation (주파수 변화에 따른 에폭시 복합체의 유전특성에 관한 연구)

  • 김상걸;이동규;안준호;이상극;오현석;박건호;박우현;이기식;이준웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.813-816
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    • 2001
  • In this paper, the dielectric properties of epoxy composites used for transformers are studied. The dielectric permittivity and loss of specimen are measured at the frequency range of 30[Hz]∼1[MHz] about temperature 20[$^{\circ}C$],100[$^{\circ}C$] and 140[$^{\circ}C$] respectively from a series of experiments. When the filler is added, between epoxy and silica is formed interface. Therefore, observed higher values of dielectric permittivity and loss in filled epoxy are attributed to MWS polarization effect. Also, glass transition temperature was shifted to higher temperature and value of dielectric permittivity and loss were decreased due to 2nd curing. Deformation of interfacial state is improved and value of dielectric permittivity and loss were decreased at low frequency region by the surface treatment of fillers with silane coupling agents.

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Simulation and Modeling of Polyethylene/Clay Nanocomposite for Dielectric Application

  • Zazoum, Bouchaib;David, Eric;Ngo, Anh Dung
    • Transactions on Electrical and Electronic Materials
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    • v.15 no.4
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    • pp.175-181
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    • 2014
  • In this paper, the simulation and modeling of a polyethylene/clay nanocomposite were undertaken to predict the nanocomposite's dielectric behavior and to help design a nanocomposite material with optimum electrical properties for electrotechnical or electronic applications. A 3-D simulation model using the finite elements method was employed in order to study the effective permittivity and electric field distribution of two-phase nanocomposite materials for ordered and random distributions of inclusions in a low-loss host matrix such as polyethylene. The influence of the dispersion of reinforcing particles, and of the permittivity and radius of the inclusions, was analysed. The simulation results were compared with alternative, known theoretical solutions obtained from classical models, and were found to be in good agreement. The numerical results also indicate that for fixed volume fractions of nanoparticles the effective permittivity of the mixture, for ordered and random distributions, does not vary with the degree of dispersion. The variation of the effective permittivity with the particle radius is shown, using numerical data, to agree with the analytical modules.

Visualization of Permittivity Distribution in GFRP using Full-Field Scanning Free Space Measurement System (전영역 스캐닝 자유공간 측정 시스템을 이용한 GFRP의 유전율 분포 가시화)

  • Hyun, Jong-Min;Ahmed, Hasan;Lee, Jung-Ryul
    • Composites Research
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    • v.31 no.3
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    • pp.99-103
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    • 2018
  • This paper visualizes the full-field permittivity distribution at the standard specimens having known electromagnetic characteristics using a scanning free space measurement (SFSM) system. First, in the two Teflon specimens with different thicknesses, the real and loss tangent of permittivity could be measured and the results agreed to the theoretical and other measurement values. Then the system has been applied to Glass/epoxy and visualized different permittivity distribution depending on the material kind. Therefore, this approach will overcome the point measurement limitation of FSM and can be used for even sub-structural full-field electromagnetic evaluation of stealth and radome structures.