Effect of pressure on normal flame velocity investigated by the initial-section method in a constant-volume vessel

1969 ◽  
Vol 2 (2) ◽  
pp. 32-37 ◽  
Author(s):  
V. S. Babkin ◽  
A. V. V'yun ◽  
L. S. Kozachenko
Keyword(s):  
Initial Section ◽  
Constant Volume ◽  
Flame Velocity ◽  
Section Method ◽  
Effect Of Pressure ◽  
Normal Flame ◽  
Normal Flame Velocity

Equations for determining normal flame velocity in a constant-volume spherical bomb

1969 ◽  
Vol 3 (2) ◽  
pp. 168-171 ◽  
Author(s):  
V. S. Babkin ◽  
Yu. G. Kononenko
Keyword(s):  
Constant Volume ◽  
Flame Velocity ◽  
Normal Flame ◽  
Normal Flame Velocity

Normal flame velocity of propane-and-air mixtures at high pressures and temperatures

1989 ◽  
Vol 25 (1) ◽  
pp. 52-57 ◽  
Author(s):  
V. S. Babkin ◽  
V. N. Bukharov ◽  
V. V. Mol'kov
Keyword(s):  
High Pressures ◽  
Flame Velocity ◽  
High Pressures And Temperatures ◽  
Normal Flame ◽  
Normal Flame Velocity

Determination of normal flame velocity and critical diameter of flame extinction in ammonia-air mixture

1978 ◽  
Vol 14 (6) ◽  
pp. 710-713 ◽  
Author(s):  
V. F. Zakaznov ◽  
L. A. Kursheva ◽  
Z. I. Fedina
Keyword(s):  
Critical Diameter ◽  
Flame Velocity ◽  
Flame Extinction ◽  
Normal Flame ◽  
Normal Flame Velocity

The Normal Flame Velocity and Analysis of the Effect of the System Parameters on This Velocity

2005 ◽  
Vol 43 (6) ◽  
pp. 937-946 ◽  
Author(s):  
Yu. V. Polezhaev ◽  
I. L. Mostinskii
Keyword(s):  
Flame Velocity ◽  
System Parameters ◽  
Normal Flame ◽  
Normal Flame Velocity

EFFECT OF PRESSURE ON THE ACID-CATALYZED ENOLIZATION OF ACETONE AND ACETOPHENONE IN VARIOUS ETHANOL–WATER SOLVENTS. ORIGIN OF THE ENTHALPY–ENTROPY COMPENSATION EFFECT

1964 ◽  
Vol 42 (8) ◽  
pp. 1835-1850 ◽  
Author(s):  
B. T. Baliga ◽  
E. Whalley
Keyword(s):  
Isotope Effect ◽  
Atmospheric Pressure ◽  
Compensation Effect ◽  
Constant Pressure ◽  
Constant Volume ◽  
Deuterium Isotope Effect ◽  
Effect Of Pressure ◽  
Effect Of Solvent ◽  
Acid Catalyzed ◽  
Ethanol In Water

The effect of pressure, temperature, and solvent composition on the rate of the acid-catalyzed enolization of acetone and acetophenone, and the solvent deuterium isotope effect for the enolization of acetophenone, have been measured by following the iodination. The solvent deuterium isotope effect [Formula: see text] for the enolization of acetophenone in 16.2% w/w ethanol–water is 2.50 ± ~0.05, which undoubtedly proves that there is a pre-equilibrium proton transfer. The effect of solvent in the range water to 33.4% w/w ethanol in water on the rate of enolization of both acetone and acetophenone is small at atmospheric pressure, but is about four times larger at 3 kbar. This cannot be explained on simple electrostatic grounds, and indicates that any simple electrostatic explanation of the solvent effect at atmospheric pressure is invalid. The volumes of activation for the enolizations are strongly dependent on the solvent, that for acetone varying from −2.l ± ~0.5 to −6.9 ± ~ 0.7 cm3 mole−1 between solvents water and 33.4% w/w ethanol in water.An examination has been made of the enthalpyentropy compensation effect. It is shown that in general if the rate or equilibrium constant of a reaction does not change with changing conditions (such as solvent, substituents, etc.) then either the quantities of activation at constant pressure, ΔHp≠ and ΔSp≠, or the corresponding quantities at constant volume, ΔUv≠ and ΔSv≠, must vary in a compensating manner, and the existence of an energy–entropy compensation effect is inevitable. For the enolization of acetone and acetophenone in ethanol–water mixtures, ΔUv≠ and ΔSv≠ vary only slightly with solvent, whereas ΔHp≠ and ΔSp≠ vary in a compensating manner. The main causes of the compensation effect in the constant-pressure parameters are, in a sense, the change with changing solvent of the thermal expansion of the solvent and of the volume of activation of the reaction. On the other hand, both the constant-pressure and the constant-volume parameters vary with substituent from acetone to acetophenone, and the constant-volume parameters vary the more.

Effect of pressure on the solvolysis of benzyl chloride in glycerol–water mixtures

1970 ◽  
Vol 48 (13) ◽  
pp. 2021-2024 ◽  
Author(s):  
D. L. Gay ◽  
E. Whalley
Keyword(s):  
Benzyl Chloride ◽  
Constant Pressure ◽  
Solvent Composition ◽  
Constant Volume ◽  
Glycerol Water ◽  
Effect Of Pressure ◽  
Solvent Dependence ◽  
Partial Volumes ◽  
Volume Energy ◽  
Entropy Of Activation

The effect of pressure up to 1.6 kbar on the rate of solvolysis of benzyl chloride in 0 to 75% v/v glycerol–water has been measured at 50 °C. The volume of activation is −10.7 ± ~ 0.4 cm3 mole−1, essentially independent of solvent composition. Therefore, the partial volumes of both benzyl chloride and the transition state depend on solvent composition in the same way. The constant-volume energy and entropy of activation are simple functions of the solvent composition, and resemble the constant-volume parameters in ethanol–water mixtures. It is concluded that constant-volume conditions are probably more appropriate than constant-pressure conditions for discussing the solvent dependence of these solvolyses.

Analysis of flame kernel development with Schlieren and laser deflection in a constant volume combustion chamber

2002 ◽  
Vol 216 (7) ◽  
pp. 581-590 ◽  
Author(s):  
J Song ◽  
M Sunwoo
Keyword(s):  
Combustion Chamber ◽  
Dwell Time ◽  
Constant Volume ◽  
Flame Velocity ◽  
Ignition Energy ◽  
Schlieren Method ◽  
Kernel Development ◽  
Flame Kernel ◽  
Constant Volume Combustion ◽  
Constant Volume Combustion Chamber

The purpose of this study is to investigate the relation between ignition systems (or energy) and flame kernel development. In this research, three different kinds of ignition systems and several different kinds of spark plug electrodes are designed and manufactured. The flame propagation velocity in a constant volume combustion chamber is measured by both a laser deflection method using an He-Ne laser and a Schlieren method using a high speed digital camera. In order to control the ignition energy, the dwell time is varied by a spark time controller. The results indicate that, when the ignition energy is increased by extending the dwell time, flame kernel growth accelerates. As the electrode gap width is increased, the breakdown energy is also increased, which stimulates the initial kernel development. The materials, diameter and shape of the electrode affect the discharged energy, the energy transfer efficiency and heat losses and, thus, these also affect the flame kernel development. The average difference in measurement of the flame velocity by the laser deflection method and Schlieren method is only 1.73 per cent. The laser deflection method is found to be preferable because it is more effective and employs simpler means for the analysis of flame kernel development.

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