Abstract
A multi-dimensional numerical model for micropyretic/combustion synthesis was developed and then applied to a special configuration. The configuration was chosen to illustrate the differences between one-dimensional and two-dimensional combustion. The features of the model include the melting of each constituent of the reactants and the products, and considerations of porosity for both the reactants and the products. Application of this model to the oscillatory combustion synthesis of TiB2 has been carried out, for the first time, to study two-dimensional-combustion-front movement. The model predicts higher hot-spot temperatures in a two-dimensional situation than those obtained in a one-dimensional experiment. Additionally, hot spots are noted to traverse along orthogonal directions. Some processing implications of such results are examined.
Similar content being viewed by others
Abbreviations
- APℴ,AP :
-
Finite-difference coefficients
- B :
-
Breadth of specimen (m)
- C PUA :
-
Specific heat of reactant A at 300K (J kg−1 K−1)
- C PUB :
-
Specific heat of reactant B at 300K (J kg−1 K−1)
- C P :
-
Specific heat of reactants at higher temperatures (J kg−1 K−1)
- C PU :
-
Specific heat of unreacted Reactants A and B at 300K(J kg−1 K−1)
- E :
-
Activation Energy (J mol−1)
- H :
-
Enthalpy (J kg−1)
- K :
-
Dimensionless thermal conductivity
- K U :
-
Thermal conductivity of the reactants A, B at 300K(W m−1K−1)
- K 0 :
-
Frequency factor (s−1)
- δH SLA :
-
Latent heat release at the melting point of Reactant A (J kg−1)
- n :
-
New time level
- o :
-
Old time level
- m :
-
Iteration number
- K * :
-
Thermal conductivity of A, B and AB in the reaction zone (W mK−1)
- L :
-
Length of specimen (m)
- M :
-
Melting parameter
- Q :
-
Heat of reaction (J kg−1)
- R :
-
Universal gas constant (J mol−1 K−1)
- t :
-
Time (s)
- T :
-
Temperature (K)
- T C :
-
Combustion temperature (K)
- T 0 :
-
Ambient temperature (K)
- X, Y :
-
Dimensionless co-ordinates
- X *,Y * :
-
Co-ordinates (m)
- ρ:
-
Density of reactants at 300 K (kg m−3)
- Ø:
-
Dimensionless enthalpy
- θ:
-
Dimensionless temperature
- Τ:
-
Dimensionless time
- η:
-
Dimensionless fraction of reacted product
- n :
-
Northern side of control volume
- N :
-
Northern control volume
- P :
-
Centre of current control volume
- s :
-
Southern side of control volume
- S :
-
Southern control volume
References
J. B. HOLT and Z. A. MUNIR,J. Mat. Sci. 21 (1986) 251.
K. A. PHILPOT, Z. A. MUNIR and J. B. HOLT,ibid. 22 (1987) 159.
H. P. LI, S. BHADURI, and J. A. SEKHAR,Metall. Trans. A 23 (1992) 251.
C. T. HO and J. A. SEKHAR, ‘High temperature ordered intermetallic alloys’, Materials Research Society, Pittsburgh, PA, (1991) 1057.
A. G. MERZHANOV and B. I. KHAIKIN,Prog. Energy Combust. Sci. 14 (1988) 1.
Y. S. NAIBORODENKO and V. I. ITIN,Comb. Explos. Shock Wave 11 (1975) 293.
J. PUSZYNSKI, J. DEGREVE and V. HLAVACEK,Ind. Engng. Chem. Res. 26 (1987) 1424.
K. G. SHKASHINSKII, B. I. KHAIKIN and A. G. MERZHANOV,Comb. Explos. Shock Waves 7 (1971) 15.
S. B. MARGOLIS, H. G. KAPER, G. I. LEAF and B. J. MATKOWSKY,Combust. Sci. Technol. 43 (1985) 127.
M. G. LAKSHMIKANTHA, A. BHATTACHARYA and J. A. SEKHAR,Metall. Trans. A 23 (1992) 23.
M. G. LAKSHMIKANTHA and J. A. SEKHAR,ibid. 24 (1993) 614.
E. A. BRANDES, “Smithells metals reference book”, 6th Edn, (Butterworth, London, 1976).
“Materials hand book for refractories: traditional and advanced ceramics” (Ceramic Industry, McGraw-Hill, New York, in press, 1991).
G. V. SAMSONOV and I. M. VINITSKII, “Handbook of refractory compounds”, (IFI/Plenum, New York, 1980) 128.
H. P. LI and J. A. SEKHAR,J. Mater. Res. 8(10) (1993).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lakshmikantha, M.G., Sekhar, J.A. Influence of multi-dimensional oscillating combustion fronts on thermal profiles. J Mater Sci 28, 6403–6408 (1993). https://doi.org/10.1007/BF01352204
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01352204