• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.2
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• pp.26-36
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• 2007

The thermal response characteristics of nozzle liner for a solid rocket motor applying highly aluminized PCP or HTPB propellant with slotted tube grain have been investigated. The SEM photographs of aluminum oxide particles taken from nozzle liner show that the PCP propellant with the finer and less contents of oxidizer can offer greater possibility for increasing aluminum agglomeration than the HTPB propellant. The PCP propellant shows locally greater mechanical erosion at 4 circumferential areas of the nozzle entrance in line with grain slot due to the impingement of large particles, but the HTPB propellant shows greater thermochemical ablation at the nozzle blast tube, the throat insert and the exit cone because of relatively much more mole fraction of $H_2O\;and\;CO_2$ in combustion gases.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.1
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• pp.36-44
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• 2018

The thermal response of carbon/phenolic used in a solid rocket nozzle liner was analyzed. In this paper, the numerical analysis of the thermal response of carbon/phenolic consists of (1) the integration equation of the boundary layer to obtain the convective heat transfer coefficient of the combustion gas on the rocket nozzle wall and (2) 1-D finite difference method for heat conduction of carbon/phenolic to calculate the ablation, char, and temperature. The calculated result was compared with the result of a blast-tube-type test motor. It is found that the calculated result shows good agreement with the thermal response of the test motor, except at the vicinity of the throat insert.