• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.1
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• pp.78-85
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• 1999

Burning characteristics of solid propellants embedded with four kinds of metal wires(Ag, Cu, Al, Ni-Cr wire) were studied with varying wire diameters(O.10.8 mm) lot N-5 propellant. It was found that the order of the burning rate increment ratio($r_w$/$r_sb$) was Ag wire > Cu wire > Al wire> Ni-Cr wire which was the same as the order of the magnitude of thermal diffusivity. The burning rate increment ratio($r_w$/$r_sb$) of N-5 propellant was less than that of composite Propellant because of the difference of adiabatic flame temperature and flame structure. When Ag, Cu and Al wire having high thermal diffusivity were embedded in N-5 propellant, the plateau and mesa characteristics of the double base propellant were disappeared, but not disappeared in the case of propellant embedded with Ni-Cr wire due to its poor thermal conductivity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.225-228
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• 2007

The objective of this study is to characterize design parameters of rocket igniters for composite, double base and nitramine propellant. Arc image furnace and fiber optics surface reflectometer were used to measure ignition delay time and reflected optical energy of several compositions of composite, double base and nitramine base rocket propellant at different pressure levels each other. The order of ignitability was double base > composite > Nitramine propellants at initial pressure of over 75 psia. The highest ignition energy was needed to ignite nitramine propellant, however, as the pressure increased up to the range of $75{\sim}400$ psia as the ignition delay time decreased abruptly. The absorbtion of radiation energy could be increased by the addition of small amount of opacifiers as carbon black, ZrC, WC and burning catalyst.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.3
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• pp.47-57
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• 2011

All solid rocket propellants are divided in two basic classes according to chemical state: homogeneous(double base) and heterogeneous (composite). Today, composite propellants are extensively used as power sources covering the range from gas generators and small rocket systems to large launch vehicles in space programs. The development of composite rocket propellants in the past was mainly directed to thermoset polymers. But, the thermoset composite propellants have the complication in formulation and fabricating process to adapt to rocket system requirements. In contrast to the thermoset propellant, the PVC plastisols composite propellants have the advantages in the view of loss in manufacturing process, low cost of raw material, and stability of the handling process even though moderate ballistic and mechanical properties. It is predicted that the application field of this class will be used more widely than any other classes.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.6
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• pp.1-8
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• 2007

The objective of the present work is to characterize design parameters of solid propellant ignitor for composite, double base, and nitramine propellants using arc image furnace. Arc image furnace and fiber optics surface reflectometer were used to measure ignition delay time and reflected optical energy of several compositions of composite, double base and nitramine base rocket propellant at different pressure levels each other. The order of ignitability was double base > composite> nitramine propellants at initial pressure of over 75 psia. The highest ignition energy was needed to ignite nitramine propellant, however, the ignition delay time decreased abruptly as the pressure increased up to the range of $75{\sim}400$ psia. The absorbtion of radiation energy could be increased by the addition of small amount of opacifiers as carbon black, ZrC, WC and burning catalyst.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.4
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• pp.61-69
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• 2019

Accelerated aging test for the double base propellant was carried out at three different temperatures (60, 70, and $75^{\circ}C$) for over a year. To evaluate the aging characteristics of the double base propellant, the stabilizer contents and thermal decomposition kinetics were analyzed by using high performance liquid chromatography (HPLC) and AKTS-Thermokinetics software. As a result, stabilizer contents in the double base propellant gradually decreased according to the aging temperature and aging duration. The consumption rate of 2-NDPA in the accelerated aged propellants showed that it was two times faster at $75^{\circ}C$ in compared with ther rate at $70^{\circ}C$. These experimental values were simulated by the SB kinetic model, and it was shown that the two-step model with constant reaction orders n1=1 and n2=0 best describes the process of the stabilizer depletion for the double base propellant.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.10a
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• pp.31-31
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• 1999

로켓 모터 내에서 높은 충전률을 유지하면서 연소면적을 증대시켜 추력기체 생성량을 증대시키는 가장 효율적인 방법으로는 금속선, 필라맨트, strip, rod 등의 열전도체와 hollow fiber를 단면연소 그레인에 삽입시키는 방법이 있다. 이러한 연구는 1950년대 ARC의 Rumbel에 의해 PVC와 AP가 주성분인 혼합형 추진제를 대상으로 처음 시도되었으며, Kubota, Caveny, Gossant, King등에 의해 복기추진제와 혼합형 추진제를 대상으로 금속선의 종류, 직경, 형태, 수 및 기하학적 배열 등에 따른 실험적 이론적 연구가 이루어져 왔다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.369-374
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• 2011

To solve the combustion instability, especially chuffing phenomena, happened during development process of the drive-away motor that was required for cold launch system of missile, we tried various technical approaches and performed ground firing tests. The supplying content or method of ignition energy, generally that is deeply related with the chuffing phenomena, does not affect suppression of the chuffing, but the addition of 2% ZrC as a damping material is effective to suppress the chuffing. Therefore we could newly experience a special solution of the combustion instability in double base propellant.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.4
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• pp.93-98
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• 2012

To solve the combustion instability, especially chuffing phenomena, happened during development process of a drive-away motor that was required for cold launch system of missile, various technical approaches have been performed through ground firing tests. The ignition energy or its supply system, generally closely related with the chuffing phenomena, does not affect suppression of the chuffing, but the increase of characteristic length($L^*$) as well as the addition of 2% ZrC as a damping material is effective to suppress the chuffing. Therefore we could have a typical experience on the combustion instability in double base propellant.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.529-531
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• 2012

The temperature coefficient of a gun propellant could be reduced by applying an appropriate surface coating material. The burning rates of those propellants do not very strongly depend on the propellant temperature. It is a good method to increase the muzzle velocity of gun ammunitions by utilizing the permissible maximum pressure in the gun barrel independent of the propellant temperature. During this study, properties of surface coated propellants were confirmed by results in tests of a closed bomb and 40mm Gun firing, and confirmed that production of coating propellant could be possible.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.10a
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• pp.47-50
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• 2003

JA2 Propellants, made by non-solvent process, are of great interest for the tank gun propellant. This is due to high energy. The grain geometries of JA2 and modified JA2 propellant were designed for application to 105mm APFSDS projectile. The combustion, thermochemical, and interior ballistic properties of the propellant were tested and calculated. The performances of the propellant were evaluated out using 105mm slug T2 projectiles and 105mm tank gun. The muzzle velocity of the propellants was higher than that of the KM30 for K274 projectile.