TY - JOUR
T1 - Reaction kinetics and a physical model of the charring layer by depositing Al2O3 at ultra-high temperatures
AU - Guan, Yi Wen
AU - Li, Jiang
AU - Liu, Yang
AU - Yan, Qi Long
N1 - Publisher Copyright:
© the Owner Societies.
PY - 2018
Y1 - 2018
N2 - The thermochemical ablation of insulation material caused by slag deposition in solid rocket motors has increasingly attracted researchers' attention. Understanding the ablation mechanism and the ability to calculate reaction kinetics parameters determine the height of the thermal protection design for advanced solid rocket motors. In this work, the interaction of the Al2O3-C system is determined through static ablation experiments. Using X-ray diffraction, HSC thermodynamic software, and a thermogravimetric analyser, the carbon thermal reduction of alumina is analysed and the reaction mechanism and physical model are obtained. Isothermal experiments at 1700-1850 °C and mathematical analysis provide the kinetic parameters of the overall and step-by-step reactions. The results show that the overall reaction of the Al2O3-C system involves three steps. The overall reaction kinetics are described by the contracting area model R2 with apparent activation and frequency factors estimated as 254.5 kJ mol−1 and 5.5 × 106 min−1, respectively. The distribution reaction kinetics of steps 1 and 2 are described by the first-order chemical reaction control model (F1) and that of step 3 is described by the one-dimensional diffusion control model (D1). The corresponding activation energies are 107.9 kJ mol−1, 240.3 kJ mol−1, and 567.5 kJ mol−1, and frequency factors are 625.94 min−1, 8.3 × 105 min−1, and 1.6 × 1014 min−1, respectively.
AB - The thermochemical ablation of insulation material caused by slag deposition in solid rocket motors has increasingly attracted researchers' attention. Understanding the ablation mechanism and the ability to calculate reaction kinetics parameters determine the height of the thermal protection design for advanced solid rocket motors. In this work, the interaction of the Al2O3-C system is determined through static ablation experiments. Using X-ray diffraction, HSC thermodynamic software, and a thermogravimetric analyser, the carbon thermal reduction of alumina is analysed and the reaction mechanism and physical model are obtained. Isothermal experiments at 1700-1850 °C and mathematical analysis provide the kinetic parameters of the overall and step-by-step reactions. The results show that the overall reaction of the Al2O3-C system involves three steps. The overall reaction kinetics are described by the contracting area model R2 with apparent activation and frequency factors estimated as 254.5 kJ mol−1 and 5.5 × 106 min−1, respectively. The distribution reaction kinetics of steps 1 and 2 are described by the first-order chemical reaction control model (F1) and that of step 3 is described by the one-dimensional diffusion control model (D1). The corresponding activation energies are 107.9 kJ mol−1, 240.3 kJ mol−1, and 567.5 kJ mol−1, and frequency factors are 625.94 min−1, 8.3 × 105 min−1, and 1.6 × 1014 min−1, respectively.
UR - http://www.scopus.com/inward/record.url?scp=85054078212&partnerID=8YFLogxK
U2 - 10.1039/c8cp04169e
DO - 10.1039/c8cp04169e
M3 - 文章
C2 - 30221294
AN - SCOPUS:85054078212
SN - 1463-9076
VL - 20
SP - 24418
EP - 24426
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
IS - 37
ER -