Highly vibrationally excited CO generated in a low-temperature chemical reaction between carbon vapor and molecular oxygen

Jans, Elijah; Frederickson, Kraig; Yurkovich, M.; Musci, B.; Rich, John Martin; Adamovich, Igor V.

doi:10.1016/j.cplett.2016.07.016

Cited by 5 publications

(12 citation statements)

References 11 publications

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“…5, suggesting that carbon is either ablated as large agglomerates (Cn, n > 16) or solid particulates, as atomic carbon vapor, or re-deposited onto the large diameter (12 mm) powered electrode. The measured C atom vapor generation rate in the arc discharge cell is much lower than the flow rate used in our previous experiments generating vibrationally excited carbon in a reaction between C atoms and molecular oxygen, which was 15 SLM (~ 0.6•10 22 atoms/s) [3,5]. Based on the previous study of an optically pumped CO laser [4], we estimate that the rate of C atom production in the arc discharge needs to be scaled up by approximately three orders of magnitude, to achieve optical gain sufficient for laser power generation.…”

Section: Resultsmentioning

confidence: 67%

“…Figure 8 shows a typical CO fundamental emission spectrum in the observation cell at these conditions. Comparison with synthetic spectra [3] shows that CO vibrational levels up to v=6 are populated and radiating, indicating strong vibrational excitation of CO chemical reaction product. No CO2 emission from the flow was detected at these conditions.…”

Section: Resultsmentioning

confidence: 98%

“…In our previous work [3], we demonstrated formation of highly vibrationally excited CO, up to at least v=14, with absolute population inversions at v=4-7, in collision-dominated environments (P=15-20 Torr) and at low rotational-translational temperatures (T=400-450 K). These results demonstrate the feasibility of development of a new CO chemical laser using carbon vapor and oxygen as reactants.…”

Section: Introductionmentioning

confidence: 79%

“…A high fraction of the reaction enthalpy stored in the CO vibrational mode (at least 10-20%) inferred from the data of Ref. [3] suggests that this laser may operate at high efficiency. In particular, a recent study, which demonstrated lasing in optically pumped CO-Ar mixtures at T≈300-400 K and P=10 Torr, at CO partial pressures of ~ 0.2-0.3 Torr [4] suggests that vibrational excitation of CO in a chemical reaction between carbon and oxygen may be used for laser power generation at these operating conditions.…”

Section: Introductionmentioning

confidence: 95%

“…Chemical lasers utilize these types of chemical reactions, where chemical energy is stored in internal modes of the products and is extracted via the stimulated emission process, generating laser power. Recent theoretical and experimental studies of the exothermic reaction of atomic carbon and molecular oxygen [1][2][3] have demonstrated that a significant fraction of the excess chemical energy (up to ~ 30%) can be stored in the vibrational mode of the carbon monoxide product. These results suggest a potential development of a chemical carbon monoxide laser based on this reaction.…”

Section: Introductionmentioning

confidence: 99%

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Scaling Up Generation of Vibrationally Excited CO in a Chemical Reaction between Carbon Vapor and Oxygen

Jans

Frederickson

Gulko

et al. 2018

2018 AIAA Aerospace Sciences Meeting

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Carbon products generated in a DC arc discharge with graphite electrodes sustained in argon buffer are characterized using time-resolved mass spectra measured by a Residual Gas Analyzer (RGA). The results show that atomic carbon vapor is one of the dominant vapor-phase components produced in the discharge. The yield of C atoms is much higher compared to that of C2 molecules. C3 signal exhibits essentially no dependence on the arc current and may be due to carbon particulates accumulated on the walls of the discharge cell from the previous runs. The yield of heavier carbon species (up to C17) is insignificant. However, the atomic carbon vapor yield is approximately two orders of magnitude lower than the net rate of carbon electrode consumption, indicating that carbon may be ablated from the electrodes as solid particulates. Carbon atoms produced in the arc discharge are used to generate highly vibrationally excited CO by a chemical reaction with molecular oxygen, added to the flow downstream of the discharge cell. Based on previous CO laser experiments, it is estimated that the rate of C atom production in the arc discharge needs to be scaled up by approximately three orders of magnitude, to achieve optical gain sufficient for laser power generation. To increase the high-temperature plasma volume up to several cm 3 , inductively coupled RF discharge is used. Fourier Transform Infrared (FTIR) emission spectroscopy was used to measure temperature in the Inductively Coupled Plasma (ICP) sustained in argon flow seeded with 2.5% CO. Temperatures up to T=2600 K were observed at a discharge power of 1 kW in the ICP. Micron-size carbon particles added to the argon flow using a custom-designed particle seeder are vaporized in the ICP discharge cell, and the products are injected into the main argon flow. Oxygen is injected into the main flow downstream of the ICP discharge cell. Vibrationally excited CO is formed by a chemical reaction between carbon vapor and oxygen in the main flow, at a relatively low temperature of T=400 K. CO vibrational levels up to v=6 are detected from FTIR emission spectra. Further experiments quantifying the yield of vibrationally excited CO are underway.

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Section: Resultsmentioning

confidence: 67%

Section: Resultsmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 79%

Section: Introductionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations