• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.5
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• pp.60-66
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• 2008

Each weapon system's muzzle velocity can be used as basic data for operating accurate automatic firing control system. Even among the same kind of ammunition, despite taking into consideration various battlefield parameters, irregular performance causes difficulties in obtaining accurate muzzle velocity data. In this study, pressure in the gun barrel was measured, the experimental relationship between chamber pressure and the projectile's base pressure was found, and a method of obtaining muzzle velocity was researched. Through this method, data regarding muzzle velocity is offered that corrects irregular performance.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.208-216
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• 2007

As the propellant mass is being accelerated out of the gun chamber along with the projectile, a continuous pressure gradient exists between the end of chamber and the base of the projectile. For this reason, the base pressure-travel curve is very important to design a conventional gun barrel in the interior ballistics, but it is not obtained briefly by empirical or theoretical method. In this paper, a simple relation between chamber pressure and base pressure was determined by the factor of base pressure(Cb) obtained from the experimental method. The simple relation gives a reasonable prediction for the reduction of pressure between the breech and the base of projectile owing to the axial gradient in the gun tube. The predictions have been validated by the infrared screen sensor and the PRODAS(PROjectile Design and Analysis System) for interior ballistic systems. Therefore, the base pressure-travel curve could be calculated from the chamber pressure measured by piezoelectric sensor. The base pressure-travel curve obtained from the simple relation offers initial information to gun barrel designer and is used for calculation of muzzle velocity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.10a
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• pp.43-46
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• 2003

This study was conducted via diagnostics in a transparent 120mm tank gun chamber simulator. Pressure rises at the breech and forward ends of the simulator chamber were measured by using PCB pressure gages. This technique has been used to develope of various advanced HEAT and KE rounds of 120mm tank gun. In the studies, many ignition phenomena occurring during the early phase of the ballistic cycle was observed and analyzed. It can provide insights into the functioning of the igniter, flame spreading, and formation of pressure waves in the gun chamber.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.520-526
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• 2012

The appearance of the negative differential pressure(NDP), in which the shot base pressure is higher than the breech pressure, indicates that a potential damage on the gun system is increased. In order to safeguard the gun system, the igniter must be designed to minimize the NDP during the firing process. From this reason, the effect of igniter's burning rate on the NDP of the interior ballistics has been investigated through the numerical simulations. The NDP has been increased with increment of the coefficient in the burning rate of the igniter. A sudden change of the chamber pressure has been shown in case of using a singular coefficient.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.1
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• pp.72-78
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• 2012

The position effect of the solid propellant in the combustion chamber on the decrease of the differential pressure has been investigated using the IBcode. Generally the metallic cartridge or CCC (combustible cartridge case) are used to load the propellant of the gun propulsion system. The position of the cartridge(propellant) is, therefore, a major factor for the interior ballistics in case the combustion chamber is larger than the cartridge. In this study, three different positions in the empty space of the chamber have been considered. As results, the case of the propellant located in the region near the base and breech has shown that the negative differential pressure and the difference between the breech pressure and the base pressure are much higher than those of the case of the propellant located in the center of the chamber. The case of the propellant in the center of the chamber is, therefore, more profitable to improve the performance of the interior ballistics.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.953-961
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• 2011

A numerical model of the igniter for the interior ballistics has been developed combining the lumped parameter model with the theoretical equation of the orifice. With the developed model of the igniter, the numerical study on characteristics of the interior ballistics according to the igniter configuration in terms of the igniter length, the side hole diameter, and the distribution of side holes has been conducted. As results of the calculation of the pressure difference between the breech and shot base, the low frequency oscillations have been influenced by the igniter length, while the high frequency oscillations have been affected by the side hole diameter and the distribution of side holes.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.2
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• pp.105-113
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• 2013

A numerical model of the igniter for the interior ballistics has been developed by combining lumped parameter model with the theoretical equation of orifice. With the developed model of the igniter, the numerical study on characteristics of the interior ballistics has been conducted according to the igniter configuration in terms of igniter length, side hole diameter, and distribution of side holes. As results of the calculation of the pressure difference between the breech and shot base, the low-cycle oscillations have been influenced by the igniter length, while the high-cycle oscillations have been affected by the side hole diameter and the distribution of side holes.