Kinetic studies of high-temperature carbon- silica reactions in charred silica-reinforced phenolic resins.

Blumenthal, Jane; Burns, E. A.; Santy, M.J.

doi:10.2514/3.3603

Cited by 37 publications

(17 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Carbon from pyrolyzed polymers is generally very reactive as indicated by the rates reported by Ono and Kurachi (1991) and Shimoo et al (1990). The reaction rates estimated for previously reported carbon blacks (Blumenthal et al, 1966;Kuznetsova et al, 1980), using the rate equation derived in this work, are slightly lower than those reported by the previous investigators. This may be the result of differences in metal impurities within the carbon blacks.…”

Section: Comparison To Reported Resultscontrasting

confidence: 52%

“…A number of researchers (Blumenthal et al, 1966;Henderson and Tant, 1983; Kennedy and North, 1983; Kevorkijan et al, 1989Kevorkijan et al, , 1992 Khalafalla and Haas, 1972; Klinger et al, 1966; Krstic, 1992; Kurosawa et al, 1966; Kuznetsova et al, 1980; Lee et al, 1976; Lee and Cutler, 1975;Miller et al, 1979; Ono and Kurachi, 1991; Papin et al, 1972; Shimoo et al, 1990;van Dijen and Metselaar, 1991;Viscomi and Himmel, 1978;and Wei et al, 1984) have investigated the reaction kinetics of the overall carbothermal reduction reaction (Eq. 1).…”

Section: Kineticsmentioning

confidence: 99%

See 1 more Smart Citation

Kinetics of carbothermal reduction synthesis of beta silicon carbide

et al. 1993

View full text Add to dashboard Cite

show abstract

Section: Comparison To Reported Resultscontrasting

confidence: 52%

Section: Kineticsmentioning

confidence: 99%

Kinetics of carbothermal reduction synthesis of beta silicon carbide

et al. 1993

View full text Add to dashboard Cite

show abstract

“…Another important parameter for the process of SiC synthesis is the time of full silica conversion into silicon carbide. Several groups have performed various kinetic studies on SiC synthesis applying different reaction conditions and carbon/silica precursors (see, for instance, [12,[14][15][16][17][18]). Although the activation energies reported varied from 230 to 550 kJ/mol, there is a general consistency that the reaction rate increases when the temperature is higher, the precursor particle size is finer, and CO is removed.…”

Section: Resultsmentioning

confidence: 99%

TGA-DSC-MS analysis of silicon carbide and of its carbon-silica precursor

Tishchenko¹,

Ilchenko²,

Kuzema³

2015

Him. Fiz. Tehnol. Poverhni

View full text Add to dashboard Cite

“…Substituting Eqs. (15) and (20) into Eq, (19) = 1™P L v w d ~ </>)/(! -w)] + K R e~El RT (20) Also, the interface velocity of the liquid-phase can be expressed as…”

Section: Physical Properties and Chemical Reactionsmentioning

confidence: 99%

Surface ablation of silica-reinforced composites.

Hsieh

Seader

1973

AIAA Journal

View full text Add to dashboard Cite

The ablation mechanism of a silica-reinforced composite is studied. Special attention is given to the effects of the presence of gas bubbles within the molten layer and certain internal chemical reactions. The assumption of two-phase laminar-flow for the melt layer is used to characterize the process. The physical properties which appear in the governing equations are considered as functions of the void fraction within the molten layer. The governing equations of change are simplified by adopting the model of constant drift velocities and are solved by the integration method. The void fraction is shown to have a substantial effect on the heat of ablation. The presence of gas bubbles affects the apparent viscosity, the effective thermal conductivity, the carbon-silica reactions, and the flow pattern of the molten layer. These effects vary with the magnitude of the stagnation enthalpy. Nomenclature a = constant of the viscosity equation C p = specific heat, cal/g °K E = activation energy, cal/mole g = acceleration due to gravity, cm/sec 2 h = enthalpy per unit mass, cal/g h T = total energy denned by Eq. (42), cal/g H eff = heat of ablation = q s /(m a + m p ), cal/g H f = heat of fusion, cal/g H p = heat of pyrolysis, cal/g H R = heat of carbon-silica reaction, cal/g K -thermal conductivity; also coefficient of apparent viscosity when not subscripted, cal/sec cm°K K e = effective thermal conductivity of the molten layer, cal/sec cm°K K R = carbon-silica reaction rate constant, g/cm 2 sec m = gas mass transfer rate, g/sec cm 2 m a = rate of formation of char, g/sec cm 2 m f = interface gas mass transfer rate, g/sec cm 2 m p = rate of pyrolysis gas formation, g/sec cm 2 m R = rate of formation of gas from carbon-silica reaction, g/sec cm 2 M = ratio of molecular weight of gas phase to air n = exponential coefficient of viscosity p = pressure, atm p' = pressure gradient in x direction, dp/dx, atm/cm p" = dp'/dx, atm/cm 2 p v = partial pressure of vaporized silica, atm Pr = Prandtl number q = heat flux, cal/cm 2 sec q c = conductive heat flux, cal/cm 2 sec q s = heat-transfer rate to the nonablative surface, cal/cm 2 sec r = body dimension measured normal to the axis of revolution, cm R = gas constant, 1.987 cal/g-mole°K R b = radius of the blunt body, cm T = temperature, °K AT-7;-r o ,°K -u = velocity component in the x direction, cm/sec u gj = drift velocity of the gas phase in the x direction, cm/sec v = velocity component in the y direction, cm/sec v gj = drift velocity of the gas phase in the j; direction, cm/sec v w = ablation velocity, cm/sec V -velocity vector, cm/sec w = mass fraction of the pyrolysis gases x = coordinate parallel to the body surface, cm y = coordinate normal to the body surface, cm a = thermal diffusivity, cm 2 /sec p = volume fraction of the liquid phase in the molten layer, (!-) S = molten layer thickness, cm 6 T = thermal layer thickness, cm e = geometric constant H = viscosity, g/cm sec H m = apparent viscosity of gas-liquid mixture, g/cm sec p = density, g/cm 3 T = shear stress, dyne...

show abstract

Kinetic studies of high-temperature carbon- silica reactions in charred silica-reinforced phenolic resins.

Cited by 37 publications

References 4 publications

Kinetics of carbothermal reduction synthesis of beta silicon carbide

Kinetics of carbothermal reduction synthesis of beta silicon carbide

TGA-DSC-MS analysis of silicon carbide and of its carbon-silica precursor

Surface ablation of silica-reinforced composites.

Contact Info

Product

Resources

About