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A comprehensive review of thermal decomposition and combustion of ammonium dinitramide (ADN) has been conducted. The basic
thermal properties, chemical pathways, and reaction products in both the condensed and gas phases are analyzed over a broad
range of ambient conditions. Detailed combustion-wave structures and burning-rate characteristics are discussed. Prominent
features of ADN combustion are identified and compared with other types of energetic materials. In particular, the influence
of various condensed- and gas-phase processes in dictating the pressure and temperature sensitivities of the burning rate
is examined. In the condensed phase, decomposition proceeds through the mechanisms ADN → NH4NO3 + N2O and ADN → NH3 + HNO3 + N2O, the former mechanism being the basic one. In the gas phase, the mechanisms ADN → NH3 + HDN and ADN → NH3 + HNO3 + N2O are prevalent. The gas-phase combustion-wave structure in the range of 5–20 atm consists of a near-surface primary flame
followed by a dark-zone temperature plateau at 600–1000°C and a secondary flame followed by another dark-zone temperature
plateau at 1000–1400°C. At higher pressures (60 atm and above), a final flame is observed at about 1800°C without the existence
of any dark-zone temperature plateau. ADN combustion is stable in the range of 5–20 atm and the pressure sensitivity of the
burning rate has the form r
b = 20.72p
0.604 [mm/sec] (p = 0.5–2.0 MPa). The burning characteristics are controlled by exothermic decomposition in the condensed phase. Above 100
atm, the burning rate is well correlated with pressure as r
b = 8.50p
0.608 [mm/sec] (p = 10–36 MPa). Combustion is stable, and intensive heat feedback from the gas phase dictates the burning rate. The pressure
dependence of the burning rate, however, becomes irregular in the range of 20–100 atm. This phenomenon may be attributed to
the competing influence of the condensed-phase and gas-phase exothermic reactions in determining the propellant surface conditions
and the associated burning rate.
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Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 6, pp. 54–79, November–December, 2005. 相似文献
3.
Experimental values of the burning rate with variations in pressure and initial temperature are given, and identity of gasification
laws in the wave for RDX and HMX is demonstrated. Differential parameters (sensitivities) of the burning rate and surface
temperature are found. Based on these parameters, response functions of the burning rate to pressure oscillations are calculated.
The calculations are performed with and without allowance for condensed phase melting. Allowance for melting is shown to reduce
the amplitude of the real part of the response functions, while the thickness of the melted layer does not produce any significant
effect on the response functions. Errors of calculating the response functions are presented. The calculated response functions
are compared with experimental data.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 3, pp. 72–82, May–June, 2007. 相似文献
4.
V. P. Sinditskii V. Yu. Egorshev M. V. Berezin V. V. Serushkin S. A. Filatov A. N. Chernyi 《Combustion, Explosion, and Shock Waves》2012,48(2):163-176
The combustion of binary compositions of nitramines (HMX, RDX, Bi-HMX, and CL-20) with two nitro ester binders, one of which
is characterized by gas-phase combustion, and the other by the burning-rate controlling reaction in the condensed phase, was
studied in the pressure range 2–15 MPa. It is shown that in compositions with the binder characterized by gas-phase combustion,
HMX in concentrations up to 50% acts as an inert additive. Depending on the size and concentration of HMX particles, three
types of combustion of the mixtures can be identified: combustion along the binder layers, combustion as a single system,
and the model of combustion with a coolant. At higher nitramine concentrations, combustion control passes to nitramine, and
the burning-rate controlling reaction occurs in the liquid phase of nitramine. For Bi-HMX and CL-20 nitramines, which are
less stable and more fast burning than HMX and in a mixture with a binder characterized by gas-phase combustion, only two
combustion models are observed: the model with fast burning additives or combustion as a single unit. In compositions of the
nitramines RDX and HMX with a binder burning by the c-phase mechanism, the combustion model with fast burning additives is
applicable only in a narrow range of conditions. The compositions mostly burn only as a single unit, and the addition of nitramine
increases the burning rate of nitro ester by transferring heat from the overlying zone to the condensed phase. 相似文献
5.
B. V. Novozhilov 《Combustion, Explosion, and Shock Waves》1968,4(4):276-282
Conclusions A comparison of the results of the theory outlined above and the experimental data shows that theory and experiment are in
qualitative agreement. Thus, taking into account the variability of the surface temperature eliminates the principal difficulty
of the theory with constant temperature—instability of the steady—state regimes of propellant combustion under ordinary practical
conditions (k>1)—and, hence, leads to the possibility of investigating nonstationary phenomena associated with the combustion
of actual systems. It is also possible to explain experimental facts such as combustion stability in a chamber and the existence
of a natural frequency of the burning rate oscillations. The order of the frequency and its pressure dependence are in agreement
with experiment. The theory is also in qualitative agreement with experimental data on quenching and on the nonstationary
burning rate at variable pressure. A number of problems remain to be investigated from the standpoint of the theory described;
for example, the dynamic erosive burning regime, or a propellant burning in the presence of a variable-velocity gas flow at
its surface.
Further development of the theory and its quantitative comparison with experiment must be based on the steady-state dependences
of burning rate and surface temperature on initial temperature and pressure. To obtain these relations is the primary task
of experimenters and theorists in the area of steady-state combustion.
In conclusion, the directions to be followed are now plain: it is necessary to account for the inertia of the reaction layer
in the condensed phase and to improve the theory by accounting for the variability in the thermal diffusivity of the propellant,
which increases with temperature. As calculations show [46, 47], this effect increases the regions of stable combustion at
constant pressure and possible oscillatory combustion modes.
Fizika Goreniya i Vzryva, Vol. 4, No. 4, pp. 482–493, 1968
Contribution to a group discussion on the unstable and nonstationary combustion of condensed systems.
19680715 相似文献
6.
Yu. M. Mikhailov V. V. Aleshin V. N. Leonova 《Combustion, Explosion, and Shock Waves》2007,43(3):334-338
In systems filled by inert additives, combustion of cellulose nitrate (CN) proceeds in a flameless low-temperature regime
with a low linear burning rate. At a standard temperature, the exponent in the low of CN combustion in ballasted mixtures
with inert additives in the pressure range of 0.1 to 10 MPa is several times lower than that of pure cellulose nitrate and
amounts to 0.23. The qualitative and quantitative composition of gaseous products of flameless CN conversion is found. It
is noted that this composition approximately corresponds to data available in the literature for the products of thermal decomposition
of cellulose nitrate at comparatively low temperatures. Based on this fact and on a weak dependence of the CN burning rate
on pressure in ballasted systems, the process under these conditions is assumed to be controlled by conversion of the energetic
component predominantly in the condensed phase. In the case of a composite consisting of cellulose nitrate, silicon carbide,
and polymer binder, for samples 10–25 mm in diameter, armoring exerts practically no effect on combustion parameters. Combustion
of the same mixture with smaller diameters of non-armored samples is unstable. The presence of a liner establishes a clearly
expressed critical combustion diameter in the examined systems.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 3, pp. 98–102, May–June, 2007. 相似文献
7.
Existing models for the erosive burning of homogeneous energetic materials ignore the fact that the burning regime can be
changed radically by exposure to a hot gas blowing over the burning surface. In other words, transition can occur from the
gasification regime at very high blowing rates (where the burning rate is determined primarily by the heat transfer from the
flow core) to the self-heating regime of the condensed phase at low or zero blowing if the heat release in the condensed phase
is sufficient to heat it to the surface temperature. A possible method for solving this problem is proposed. The approach
proposed provides a plausible explanation for the experimentally observed singular (kinked) dependence of the magnitude of
the negative erosion effect on the initial temperature.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 3, pp. 47–58, May–June, 2007. 相似文献
8.
V. M. Gremyachkin 《Combustion, Explosion, and Shock Waves》2006,42(3):254-263
A model of combustion of a high-porosity carbon particle in oxygen is considered, which takes into account heterogeneous and
homogeneous chemical reactions inside the particles and radiative heat transfer. The boundaries of the domain where the burning
rate depends on the particle temperature are determined. The possibility of two combustion regimes is demonstrated: regime
with a high burning rate, where the carbon-oxygen reaction proceeds in a layer adjacent to the particle surface, and regime
with a low burning rate, where the reaction proceeds in the entire particle volume. In the regime with a high burning rate,
the main product of the reaction between carbon and oxygen is carbon monoxide, whereas both carbon monoxide and carbon dioxide
can be formed in the regime with a low burning rate. The kinetic equations of heterogeneous reactions C + O2 = CO2 and 2C + O2 = 2CO are determined, which reveal the retarding effect of carbon monoxide and dioxide on the rates of these reactions.
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Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 3, pp. 11–22, May–June, 2006. 相似文献
9.
O. G. Glotov 《Combustion, Explosion, and Shock Waves》2006,42(4):436-449
The condensed combustion products of two model propellants consisting of ammonium perchlorate, aluminum, nitramine, and an
energetic binder were studied by a sampling method. One of the propellants contained HMX with a particle size D
10 ≈ 490 μm, and the other RDX with a particle size D
10 ≈ 380 μm. The particle-size distribution and the content of metallic aluminum in particles of condensed combustion products
with a particle size of 1.2 μm to the maximum particle size in the pressure range of 0.1–6.5 MPa were determined with variation
in the particle quenching distance from the burning surface to 100 mm. For agglomerates, dependences of the incompleteness
of aluminum combustion on the residence time in the propellant flame were obtained. The RDX-based propellant is characterized
by more severe agglomeration than the HMX-based propellant — the agglomerate size and mass are larger and the aluminum burnout
proceeds more slowly. The ratio of the mass of the oxide accumulated on the agglomerates to the total mass of the oxide formed
is determined. The agglomerate size is shown to be the main physical factor that governs the accumulation of the oxide on
the burning agglomerate.
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Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 4, pp. 78–92, July–August, 2006. 相似文献
10.
B. N. Kondrikov V. É. Annikov V. Yu. Egorshev L. T. De Luca 《Combustion, Explosion, and Shock Waves》2000,36(1):135-145
Burning of solid crystalline hydroxylammonium nitrate (HAN) and its water solutions is studied in a constant-pressure bomb
within the pressure range from 0.1 to 36 MPa. Abnormally high pressure exponents are found to be typical of combustion of
the crystalline substance, its ≈9-mole/liter water solution, and a solution containing ethanolamine nitrate as a fuel: for
pressures below ≈10 MPa, the burning rate is proportional to the 1.5–2.6 power of pressure. Crystalline HAN retains this tendency
up to ≈20 MPa, whereas the solutions burning in the turbulent regime show a sharp decrease in the pressure exponent if the
pressure exceeds 10 MPa. In some instances, as was found in previous works, the burning rate even decreases with increasing
pressure. Special features of turbulent burning are explained. A model is proposed to describe the steady-state burning of
solid HAN. Kinetic parameters of the leading reaction are derived.
Translated fromFizika Goreniya i Vzryva, Vol. 36, No. 1, pp. 149–160, January–February, 2000.
This work was partly supported by the Russian Foundation for Fundamental Research (Grant Nos. 98-32164 and 98-32167). 相似文献
11.
Combustion wave temperature profiles are determined for two low calorific value propellants (Q
c = 2189 and 2518 kJ/kg). It is shown that the structure and parameters of the combustion wave differ significantly from those
for previously studied propellants of medium (propellant N) and high (propellant NB) calorific values. At a relatively short
distance from the burning surface, the temperature is significantly (180–270 K) higher than the calculated value due to fact
the combustion products contain carbon black from the decomposition of heat-resistant dibutyl dinitrotoluene and dibutyl phthalate.
Then, part of carbon black reacts endothermically with CO2 and H2O, leading to a decrease in temperature, which for the first sample is nevertheless 100–140 K higher than the thermodynamic
value. For the investigated propellants, the activation energy of the leading reaction is the same as for the previously studied
propellants, suggesting a common decomposition kinetics of the condensed phase regardless of the propellant composition. However,
a uniform dependence of the burning rate on surface temperature is not observed. For low calorific value propellants, the
surface temperatures are close to those for propellant N although their burning rate is significantly (2–2.2 times) lower.
The causes of this fact are considered. 相似文献
12.
13.
V. A. Strunin A. V. Fedorychev S. V. Gunin A. N. Klyuchnikov Yu. M. Milekhin G. B. Manelis 《Combustion, Explosion, and Shock Waves》2007,43(6):664-673
The model of combustion of a composition consisting of a quasi-homogeneous composite propellant (matrix) and coolant particles
is considered. The model is based on the leading role of exothermal decomposition of the matrix and on the cooling effect
of the second component by virtue of transverse heat transfer between the components in the condensed and gas phases. Formulas
for combustion characteristics (temperature, burning rate, its sensitivity to pressure, and initial temperature) are derived
and analyzed. The calculated dependences of these characteristics on pressure, particle size, concentration, and thermal effects
of decomposition of the components show that transitional regimes with a stronger dependence of the burning rate on pressure
than that of the initial propellant are reached in a certain range of parameters. An algorithm is proposed, and a parametric
identification of the model on the basis of experimental data is performed.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 6, pp. 51–60, November–December, 2007. 相似文献
14.
E. M. Popenko A. A. Gromov Yu. Yu. Shamina A. P. Il’in A. V. Sergienko N. I. Popok 《Combustion, Explosion, and Shock Waves》2007,43(1):46-50
The effect of small additives (1.25–5.00%) of ultrafine aluminum powders (UFAP) on the rheology and combustion of model four-component
energetic condensed systems is studied. It is found that the addition of UFAP decreases the temperature of HMX decomposition.
Small additives of UFAP increase the burning rate of model energetic condensed systems and decrease the exponent ν in the burning rate law without deteriorating the rheological characteristics of the model propellants.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 1, pp. 54–59, January–February, 2007. 相似文献
15.
RDX-CMDB推进剂燃速温度敏感系数的实验研究 总被引:2,自引:0,他引:2
为了揭示RDX-CMDB推进剂中各常见组分对其燃速温度敏感系数的影响规律,制备了一系列含RDX、铝粉及燃烧催化剂的CMDB推进剂样品。采用氮气靶线法测得其在2~14MPa下的燃速温度敏感系数(σp)。讨论了RDX含量、铝粉、燃烧催化剂对RDX-CMDB推进剂燃速温度敏感系数的影响。结果表明,提高工作压强、增加RDX含量、添加燃烧催化剂均有助于降低RDX-CMDB推进剂在一定初始条件下的燃速温度敏感系数。配方中引入铝粉后可降低中低压下RDX-CMDB推进剂的燃速温度敏感系数,且燃速温度敏感系数几乎不随压强变化而变化。选用含邻苯二甲酸铅和没食子酸铋锆作燃烧催化剂,均可在2~10MPa下降低RDX-CMDB推进剂的燃速压强指数,同时降低燃速温度敏感系数。 相似文献
16.
K. G. Shkadinskii N. I. Ozerkovskaya V. V. Chernetsova 《Combustion, Explosion, and Shock Waves》1998,34(3):319-325
We consider a mathematical model of propagation of the combustion front in heterogeneous condensed compounds. For these compounds,
the adiabatic combustion temperature is lower than the melting point of the initial reagents and condensed products; it is
also lower than the minimum temperature of their eutectics. The chemical interaction in the combustion front is accomplished
by a gas transport mechanism due to the gasification of additive oxides. Within the framework of the investigated model, values
are obtained for the front velocity, which are of the same order as those observed experimentally. Periodic unstable combustion
regimes (fluctuating and spinning) arise when the macrokinetics of the chemical transformation is strongly activated. It is
shown that the activation can depend on the gasification energy and, consequently, the evaporation of additive oxides influences
the stability of a steady-state combustion regime.
Translated fromFizika Goreniya i Vzryva, Vol. 34, No. 3, pp. 77–83, May–June 1998. 相似文献
17.
Using numerical modeling, we have revealed the instability of a steady-state combustion regime which was previously obtained
using analytical methods in the substance-combustion model with surface vaporization and with exothermic reactions in the
condensed phase which are intense enough to form a maximum of temperature underneath the surface. The instability has been
studied analytically using the method of small perturbations to eliminate the version of its nonphysical (numerical) character.
Steady-state combustion regimes with maxima on the condensed-phase temperature profile are shown to be actually unsteady.
It is suggested that convection in a liquid-subsurface layer owing to bubble motion caused by the Marangoni effect should
be taken into account to describe correctly the experimentally observed steady-state regimes with a leading role of the condensed
phase.
Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 1, pp. 43–50, January–February, 1997. 相似文献
18.
B. V. Novozhilov 《Combustion, Explosion, and Shock Waves》2005,41(6):709-726
The review summarizes the long-term experience in theoretical research of combustion of gasifying condensed systems with periodically
varied pressure. Most results are obtained within the framework of the Zel'dovich-Novozhilov theory. The main properties of
the linear function of the burning rate response to harmonically varied pressure are discussed. The concept of nonlinear response
functions is introduced, which is illustrated by the explicit form of a number of second-order response functions. A new phenomenon
is described: bifurcations of response functions with a varied amplitude or frequency of pressure oscillations. For the simplest
gunpowder model containing three parameters only, the sequence of bifurcations of doubling of the burning rate oscillation
period is studied, which finally leads to a random combustion regime. An analytical relation between the linear response functions
to harmonically varied pressure and to an oscillating radiant heat flux is noted. An example of calculating the response function
with allowance for thermal inertia of the gas phase is presented.
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Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 6, pp. 116–136, November–December, 2005. 相似文献
19.
N. A. Kakutkina 《Combustion, Explosion, and Shock Waves》2008,44(4):388-396
A one-dimensional two-temperature model for filtration combustion of liquid monofuels is proposed. The model is used to analyze
the filtration combustion of liquid hydrazine in narrow tubes. Two steady-state regimes are found. In regime I, the dominant
mechanism of heat transfer from the combustion products in the preflame zone is heat conduction in the gas, and in regime
II, this is interfacial convective heat transfer and heat conduction in the solid phase. Parameter ranges for the existence
of the regimes are established.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 4, pp. 21–30, July–August, 2008. 相似文献
20.
G. N. Leonov 《Combustion, Explosion, and Shock Waves》2008,44(5):547-551
This paper considers the mechanisms involved in the effect of the unconnected porosity of the condensed phase of nitrocellulose
propellants on the linear burning rate with a pressure rise. A model based on experimental data is proposed for the variation
in the linear burning rate taking into account the compaction of the fuel cells resulting in a nonlinear dependence of the
burning rate on pressure. The temperature coefficient of the linear burning rate is found to exhibit a nontrivial behavior
under pressure rise conditions in various ranges of initial temperatures.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 5, pp. 58–63, September–October, 2008. 相似文献