• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.767-768
• /
• 2005

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.3
• /
• pp.32-36
• /
• 2016

Test equipment was designed and manufactured to evaluate thermal reaction characteristic of internal insulators of solid rocket motor. Test is allowed up to chamber pressure 2,500 psi, burn-time 100 s. A cross section of test sample part is quadrature, and various test samples can be comparable at the same time. Inner temperature of test sample can be measured by thermocouples during burning. Test was executed in condition of efficient average chamber pressure 1,000 psi, efficient burn-time 10 s and safety of equipment was confirmed. Basic data for understanding thermal characteristics of internal insulator, that is, pressure-time curve, temperature-time curve in the test sample, and thermal destruction thickness of test sample was gained successfully.

• Carbon letters
• /
• v.16 no.3
• /
• pp.203-210
• /
• 2015

This study fabricated low thermal conductive polyacrylonitrile (PAN)-based carbon fibers containing cellulose particles while maintaining their mechanical properties. The high thermal conductivity of carbon fibers limits their application as a high temperature insulator in various systems such as an insulator for propulsion parts in aerospace or missile systems. By controlling process parameters such as the heat treatment temperature of the cellulose particles and the amount of cellulose added, the thermal and mechanical properties of the PAN-based carbon fibers were investigated. The results show that it is possible to manufacture composite carbon fibers with low thermal conductivity. That is, thermal conductivities were reduced by the cellulose particles in the PAN based carbon fibers while at the same time, the tensile strength loss was minimized, and the tensile modulus increased.

• Proceedings of the KIEE Conference
• /
• 1997.11a
• /
• pp.345-347
• /
• 1997

The thermal decomposition kinetics of epoxy resin system as an electrical insulator for high voltage was investigated by using thermogravimetric analysis and Horowitz & Metzger equation. Epoxy resin system was degraded by one stage. The thermal decomposition activation energies of epoxy resin systems were all about 380 kJ/mol at the GN contents of 0 and 5 phr, and it abruptly decreased at 10 phr.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.193-198
• /
• 2010

In solid propellant rocket motors, $Al_2O_3$, one of combustion products, can be accumulated inside a combustion chamber. A special rocket motor was designed and tested to simulate thermal reaction of rubber insulator affected by the deposited slag. We successfully demonstrated through a dynamic radioscopy that the slag was deposited at the location as designed. In this paper we present a new test method which can simulate a high temperature and pressure environment in combustion chamber to evaluate material characteristics of rubber insulator and can provide design data to decide its thickness for a new solid rocket motor. The solid rocket motor, which has an average chamber pressure of 770 psia and a burning time of 50 seconds, was tested. The results show that erosion of EPDM insulator is more affected by a gas velocity rather than by the thermal reaction of slag with a high thermal capacity.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.15 no.3
• /
• pp.9-14
• /
• 2011

In solid propellant rocket motors, $Al_2O_3$, one of combustion products, can be accumulated inside a combustion chamber. A special rocket motor was designed and tested to simulate thermal reaction of rubber insulator affected by the deposited slag. We successfully demonstrated through a dynamic radioscopy that the slag was deposited at the location as designed. In this paper we present a new test method which can simulate a high temperature and pressure environment in combustion chamber to evaluate material characteristics of rubber insulator and can provide design data to decide its thickness for a new solid rocket motor. The solid rocket motor, which has an average chamber pressure of 770 psia and a burning time of 50 seconds, was tested. The results show that erosion of EPDM insulator is more affected by a gas velocity rather than by the thermal reaction of slag with a high thermal capacity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.07b
• /
• pp.1121-1124
• /
• 2004

Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. The diagnosis methods in off-line most are the method for virgin and last aged sample. However, the diagnosis method in on-line is method that can be evaluate sample state as progressing continuously aging test in beginning, The diagnosis method in on-line is arranged as following: leakage current measurement, electric field, surface state investigation, thermal image, emitting light measurement and then so. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination.

• Proceedings of the KIEE Conference
• /
• 2001.07c
• /
• pp.1667-1669
• /
• 2001

The clack of Insulator, which results from internal or external surges such as electrical, mechanical, and thermal stress, might cause ground fault and a power failure without proper repairs. In order to minimize losses caused by a short-term or long-term power failure, it is necessary to detect the deteriorated insulator as early as possible. To do so, we will develop a new device, which can detect and trace an deteriorated insulator by monitoring its physical change the variation of frequency spectrum. This device will do so by finding a Periodic wave sharp (120 Hz), a peculiar wave generated by defused electricity.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.90-91
• /
• 2015

Heat insulator materials can be classified inorganic and organic. The organic material is due to toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. In this study, cullet and fly ash were used as basic materials in order to secure a recycling technology of by-products which was mostly discarded and reclimed, and measure of physical properties of light-weight ceramic insulator.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.11a
• /
• pp.180-181
• /
• 2014

Heat insulator materials can be classified inorganic and organic. The organic material is due to toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. In this study, cullet and fly ash were used as basic materials in order to secure a recycling technology of by-products which was mostly discarded and reclimed, and measure of physical properties of light-weight ceramic insulator.