Spacecraft Dielectric Material Properties and Spacecraft Charging

1986 ◽  
Author(s):  
J. J. A. Wall ◽  
D. D. B. Cotts ◽  
A. A. R. Frederickson
Keyword(s):  
Material Properties ◽  
Dielectric Material ◽  
Spacecraft Charging

scholarly journals Influence of Insulating Material Properties on Partial Discharges at DC Voltage

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4305
Author(s):  
Marek Florkowski
Keyword(s):  
Material Properties ◽  
Dielectric Material ◽  
Partial Discharge ◽  
Partial Discharges ◽  
Time Interval ◽  
Post Discharge ◽  
Insulating Material ◽  
Dc Voltage ◽  
The Impact

Understanding a partial discharge mechanism at direct current (DC) is an actual research topic that requires both modeling, simulations and measurements. This paper describes an influence of insulating material properties on partial discharges at DC voltage. Modifications of the traditional model reflecting the conditions of partial discharges (PD) inception and post discharge processes at DC voltage have been proposed. The aim was to show the partial discharge mechanisms and draw attention to the role of parameters of insulation materials adjacent to the cavity at DC voltage. The investigations were performed on two kinds of dielectric material used in power cables. Various combinations of specimens were designed to reveal the effect of the material resistivity on the PD activity. Key observations referred to the impact of the void adjacent material resistance on the partial discharge inception voltage threshold at DC voltage. The modified PD model was applied to analyze both inception and post discharge recovery stage. The role of dielectric properties of material adjacent to the void was investigated, highlighting its impact during static inception stage and in charging stage. Despite many simplifications introduced in the model, measurement results have confirmed the role of the dielectric material surrounding the void on partial discharge dynamics. The average time interval between PD pulses revealed a systematic relationship with respect to the applied voltage and specimen resistivity. This value can be considered in the future research for diagnostic indicator at DC voltage.

scholarly journals Effect of organic gate dielectric material properties on interfacial charging and discharging of pentacene MIM device

2011 ◽  
Vol 14 ◽  
pp. 62-66 ◽  
Author(s):  
Kateryna Bazaka ◽  
Mohan V. Jacob ◽  
Dai Taguchi ◽  
Takaaki Manaka ◽  
Mitsumasa Iwamoto
Keyword(s):  
Material Properties ◽  
Gate Dielectric ◽  
Dielectric Material ◽  
Gate Dielectric Material

Effect of ultraviolet curing wavelength on low-k dielectric material properties and plasma damage resistance

2011 ◽  
Vol 519 (11) ◽  
pp. 3619-3626 ◽  
Author(s):  
Premysl Marsik ◽  
Adam M. Urbanowicz ◽  
Patrick Verdonck ◽  
David De Roest ◽  
Hessel Sprey ◽  
...  
Keyword(s):  
Material Properties ◽  
Dielectric Material ◽  
Ultraviolet Curing ◽  
Plasma Damage ◽  
Damage Resistance ◽  
Low K

scholarly journals Reflection phase analysis of reflectarray antenna based on paper substrate materials

2019 ◽  
Vol 13 (2) ◽  
pp. 766
Author(s):  
H. I Malik ◽  
M. Y. Ismail ◽  
S. R Masrol ◽  
Sharmiza Adnan
Keyword(s):  
Material Properties ◽  
Dielectric Material ◽  
Substrate Material ◽  
Scattering Parameters ◽  
Paper Substrate ◽  
Reflection Phase ◽  
Rectangular Patch ◽  
Reflectarray Antenna ◽  
Variable Substrate ◽  
Broadband Frequency

<span>This article presents an analysis of reflection loss and reflection phase behavior of a novel microstrip reflectarray antenna, embedded on paper substrate material. Two different paper substrates were first analyzed for dielectric material properties. A detailed analysis of scattering parameters of rectangular patch element with variable substrate heights has been carried out. Rectangular patch elements fabricated using adhesive copper tape over the paper substrate, show that a wide bandwidth is achieved compared to available conventional substrate materials. Fabricated patch elements over paper substrate material show a broadband frequency response of 340 and 290 MHz. It has also been demonstrated that the measured reflection phase ranges for both the substrate cover 310º and 294º at low phase gradients of 0.12 and 0.24 º/MHz respectively.</span>

scholarly journals Evaluation of Effective Elastic, Piezoelectric, and Dielectric Properties of SU8/ZnO Nanocomposite for Vertically Integrated Nanogenerators Using Finite Element Method

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Neelam Mishra ◽  
Braj Krishna ◽  
Randhir Singh ◽  
Kaushik Das
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Material Properties ◽  
Volume Fraction ◽  
Dielectric Material ◽  
Mechanical Energy ◽  
Zno Nanowires ◽  
Piezoelectric Composite ◽  
Fem Simulations ◽  
Element Method

A nanogenerator is a nanodevice which converts ambient mechanical energy into electrical energy. A piezoelectric nanocomposite, composed of vertical arrays of piezoelectric zinc oxide (ZnO) nanowires, encapsulated in a compliant polymeric matrix, is one of most common configurations of a nanogenerator. Knowledge of the effective elastic, piezoelectric, and dielectric material properties of the piezoelectric nanocomposite is critical in the design of a nanogenerator. In this work, the effective material properties of a unidirectional, unimodal, continuous piezoelectric composite, consisting of SU8 photoresist as matrix and vertical array of ZnO nanowires as reinforcement, are systematically evaluated using finite element method (FEM). The FEM simulations were carried out on cubic representative volume elements (RVEs). Four different types of arrangements of ZnO nanowires and three sizes of RVEs have been considered. The volume fraction of ZnO nanowires is varied from 0 to a maximum of 0.7. Homogeneous displacement and electric potential are prescribed as boundary conditions. The material properties are evaluated as functions of reinforcement volume fraction. The values obtained through FEM simulations are compared with the results obtained via the Eshelby-Mori-Tanaka micromechanics. The results demonstrate the significant effects of ZnO arrangement, ZnO volume fraction, and size of RVE on the material properties.

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