S. W. Zelazny, J. A. Blauer, L. Wood, L. H. Sentman, and W. C. Solomon, "Transfer chemical laser: modeling of a cw DF–CO2 laser," Appl. Opt. 15, 1164-1171 (1976)
The chemical kinetics characterizing a DF–CO2 transfer chemical laser were verified by utilizing a subsonic laser system which, for most conditions, could be approximated as premixed and at constant pressure. In such a laser, fluid dynamic effects are minimized, and the role of the kinetics model in characterizing the DF–CO2 system is emphasized. Predictions of zero power gain, DF(v) number densities, thermocouple temperatures, and laser power were compared with data for an optical cavity pressure range of 21–79 Torr. The results show that the kinetics model gives an accurate description of the DF–CO2 optical cavity. Mixing phenomena were found to become important at cavity pressures below 40 Torr.
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
f(v) = 2 (v′·v)
g(v) = 1.0, 1.73, 4.0, 4.92, 5.52, 5.52, 5.52, 5.52, 5.52, f or v = 1, 2, 3, 4, 5, 6, 7, 8, 9
h(v) = 0.04, 0.08, 0.13, 0.20, 0.31, 0.24 for v = 0, 1, 2, 3, 4, 5
See Table 1c
Table III
Comments Regarding Certain Rates in Tables I and II
Since Monte Carlo calculations18 indicate that D deactivates DF(v) to all levels, v′ < v, with nearly equal probability, we have assumed a similar abstraction mechanism here. The temperature dependence given by Cohen19 for the DF(v)-D system is assumed to apply here.
Rate constants for bending mode and symmetric stretching mode deactivations are related by means of the SSH Theory23 to the measured deactivation rate of the lowest bending level: CO2(0110).
We have used the V-R-T Theory of Shin27 to correct the value of k for M = H2 given by Simpson19 for the isotope effect. The SSH Theory is used to obtain the deactivational efficiency, ϕ(D) of D-atoms. The theory of Shin27 is used to find a value of k for M = DF.
When resort to theory is made for deactivation of CO2 (mnℓp) by a collision partner, the SSH Theory is used for nonhydrogenated species, otherwise. Shins V-R-T Theory27 is used.
For equilibrium among the Fermi-resonant modes of CO2, we have resorted to the SSH Theory. The resultant values are multiplied by 4.6 to normalize them to the value obtained by Stark20 for the reaction: CO2 (1000) + M = CO2(0200) + M. The collisional efficiencies observed by Stark20 are nearly reproduced by the SSH Theory23 lending confidence to use of the latter values for some species.
The product distribution for these reactions was estimated from theory23,21. The overall (global) exchange rates are based upon experimental results which have been adequately discussed in several literature reviews25,28. The collisional efficiency for NOF in these reactions has gratiously been furnished to us by Airey24.
The temperature dependence for these reactions is assumed to be intermediate between those for the HF-HF and DF-DF systems. A geometric averaging is used.
The temperature dependence for these reactions is estimated from the theory of Shin27.
Pre-exponential set equal to that for the similar reaction: H + 03 = HO + 02 see ref. 37.
The assumption is made that approximately 35% of the exothermicity of the reaction is converted to vibration of the hydrogen halide in accordance to the results of Menard38 for the reaction: H + NO Cl = NO + H Cl (v). The activation energy is assumed to be intermediate between that for the reactions: H + F2 = HF(v) + F and H + Cl2 = HCl (v) + Cl. i.e., it is assumed that they scale with the enthalpy change.
Table IV
IRIS-I Flow Conditions
Case
Cavity Pressure (torr)
αF %
ψHe
ψCO2
RL
(g/s)
(g/s)
1
21
1.00
26.0
6.5
2.6
0.23
5.8
0.48
212.0
4.97
2
33
0.74
27.0
6.8
1.6
0.23
4.3
0.47
214.0
2.98
3
40
0.64
27.0
6.6
2.3
0.23
5.6
0.54
237.0
5.01
4
49
0.50
40.0
7.1
2.6
0.24
6.2
0.47
251.0
4.87
5
56
0.34
41.0
7.0
2.6
0.13
6.5
0.48
247.0
4.92
6
79
0.24
40.0
9.4
3.6
0.13
8.8
0.48
295.0
6.98
NOTES:
1)
is Available Fluorine (F and F2)
2) Dissociation Levels from Equilibrium Calculation for the Combustor.
3) Molar Ratios
and
Refer to Compositions before Combustion, i.e., prior to heat release and F2 dissociation in the combustor.
Table V
Comparison Between Experimental and Predicted Power* for the IRIS-I TCL
50% Outcoupled, 98% Reflectivity Spherical Mirrors; Smaller Mirror: 6.7 × 4.2 cm Smaller Dimension in the Flow Direction, Radius of Curvature = 500 cm; Larger Mirror: 12.7 cm Diameter, Edge Located 1.0 cm from Nozzle Exit Plane, Radius of Curvature = 710 cm
Applies for Power, Specific Power and Specific Efficiency since P ∝ σ ∝ η
Tables (5)
Table I
Reaction Rate Data for D2–F2–CO2 Systems (1974) Reactions Involving Generalized Collision Partners
f(v) = 2 (v′·v)
g(v) = 1.0, 1.73, 4.0, 4.92, 5.52, 5.52, 5.52, 5.52, 5.52, f or v = 1, 2, 3, 4, 5, 6, 7, 8, 9
h(v) = 0.04, 0.08, 0.13, 0.20, 0.31, 0.24 for v = 0, 1, 2, 3, 4, 5
See Table 1c
Table III
Comments Regarding Certain Rates in Tables I and II
Since Monte Carlo calculations18 indicate that D deactivates DF(v) to all levels, v′ < v, with nearly equal probability, we have assumed a similar abstraction mechanism here. The temperature dependence given by Cohen19 for the DF(v)-D system is assumed to apply here.
Rate constants for bending mode and symmetric stretching mode deactivations are related by means of the SSH Theory23 to the measured deactivation rate of the lowest bending level: CO2(0110).
We have used the V-R-T Theory of Shin27 to correct the value of k for M = H2 given by Simpson19 for the isotope effect. The SSH Theory is used to obtain the deactivational efficiency, ϕ(D) of D-atoms. The theory of Shin27 is used to find a value of k for M = DF.
When resort to theory is made for deactivation of CO2 (mnℓp) by a collision partner, the SSH Theory is used for nonhydrogenated species, otherwise. Shins V-R-T Theory27 is used.
For equilibrium among the Fermi-resonant modes of CO2, we have resorted to the SSH Theory. The resultant values are multiplied by 4.6 to normalize them to the value obtained by Stark20 for the reaction: CO2 (1000) + M = CO2(0200) + M. The collisional efficiencies observed by Stark20 are nearly reproduced by the SSH Theory23 lending confidence to use of the latter values for some species.
The product distribution for these reactions was estimated from theory23,21. The overall (global) exchange rates are based upon experimental results which have been adequately discussed in several literature reviews25,28. The collisional efficiency for NOF in these reactions has gratiously been furnished to us by Airey24.
The temperature dependence for these reactions is assumed to be intermediate between those for the HF-HF and DF-DF systems. A geometric averaging is used.
The temperature dependence for these reactions is estimated from the theory of Shin27.
Pre-exponential set equal to that for the similar reaction: H + 03 = HO + 02 see ref. 37.
The assumption is made that approximately 35% of the exothermicity of the reaction is converted to vibration of the hydrogen halide in accordance to the results of Menard38 for the reaction: H + NO Cl = NO + H Cl (v). The activation energy is assumed to be intermediate between that for the reactions: H + F2 = HF(v) + F and H + Cl2 = HCl (v) + Cl. i.e., it is assumed that they scale with the enthalpy change.
Table IV
IRIS-I Flow Conditions
Case
Cavity Pressure (torr)
αF %
ψHe
ψCO2
RL
(g/s)
(g/s)
1
21
1.00
26.0
6.5
2.6
0.23
5.8
0.48
212.0
4.97
2
33
0.74
27.0
6.8
1.6
0.23
4.3
0.47
214.0
2.98
3
40
0.64
27.0
6.6
2.3
0.23
5.6
0.54
237.0
5.01
4
49
0.50
40.0
7.1
2.6
0.24
6.2
0.47
251.0
4.87
5
56
0.34
41.0
7.0
2.6
0.13
6.5
0.48
247.0
4.92
6
79
0.24
40.0
9.4
3.6
0.13
8.8
0.48
295.0
6.98
NOTES:
1)
is Available Fluorine (F and F2)
2) Dissociation Levels from Equilibrium Calculation for the Combustor.
3) Molar Ratios
and
Refer to Compositions before Combustion, i.e., prior to heat release and F2 dissociation in the combustor.
Table V
Comparison Between Experimental and Predicted Power* for the IRIS-I TCL
50% Outcoupled, 98% Reflectivity Spherical Mirrors; Smaller Mirror: 6.7 × 4.2 cm Smaller Dimension in the Flow Direction, Radius of Curvature = 500 cm; Larger Mirror: 12.7 cm Diameter, Edge Located 1.0 cm from Nozzle Exit Plane, Radius of Curvature = 710 cm
Applies for Power, Specific Power and Specific Efficiency since P ∝ σ ∝ η