Download or read book Tunable Diode Laser Gain Measurements of the HF 2 0 Overtone Transitions in a Small Scale HF Laser written by Charles F. Wisniewski and published by . This book was released on 2002 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A tunable diode laser was used to probe the overtone gain medium of a small-scale HF laser. Two-dimensional, spatially resolved small signal gain and temperature maps were generated for the P(3) ro-vibrational transition in the first HF overtone band.
Download or read book Spatially Resolved Sub Doppler Overtone Gain Measurements in a Small Scale Supersonic HF Laser written by Charles Frank Wisniewski and published by . This book was released on 2003-08-01 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overtone gain of a small-scale HF laser was measured using a sub- Doppler tunable diode laser system. Two-dimension spatially resolved small signal gain and temperature maps were generated, which show a highly inhomogeneous gain medium: indicating the dominant role that mixing of the fuel and oxidizer streams has in HF laser performance. The measured gain a temperature data were analyzed with the aid of a two-dimensional computational fluid dynamics code. To reduce uncertainty of important modeling input parameters, novel measurements of reactant concentration, flow velocity and gain length were made. Results show that reactant mixing mechanisms such as turbulence and large-scale vortex structures have a large effect on the gain averaged over a vertical profile while kinetic rate mechanisms such as reaction rate constants and reactant concentration have a greater effect on the maximum system gain. Overtone gain data measured while operating the laser saturated on the fundamental transitions are compared with fundamental lasing output spectra. In all cases, the data are consistent with an equilibrium rotational distribution.
Download or read book Proceedings of the International Conference on Lasers written by and published by . This book was released on 2001 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High power Laser Ablation written by and published by . This book was released on 2004 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas and Chemical Lasers and Applications III written by Michael C. Heaven and published by SPIE-International Society for Optical Engineering. This book was released on 2004 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of SPIE present the original research papers presented at SPIE conferences and other high-quality conferences in the broad-ranging fields of optics and photonics. These books provide prompt access to the latest innovations in research and technology in their respective fields. Proceedings of SPIE are among the most cited references in patent literature.
Download or read book Overtone Vibration laser Double Resonance Measurements of Energy Transfer Rates and Mechanisms in HF v written by Richard A. Copeland and published by . This book was released on 1982 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pulsed Hydrogen Fluoride Overtone Chemical Laser Studies written by and published by . This book was released on 1993 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study of HF chemical lasers operating on overtone transitions, OTs, in a photolytically initiated, pulsed laser facility was conducted. The primary objective was to obtain comparisons of the specific energy performance of pulsed HF, chain reaction driven, chemical laser resonators when operating only on fundamental transitions, delta V = 1, and only on first overtone transitions, delta V = 2. The initial efforts were the buildup of the experimental test facility with which excellent performance as an FT HF laser was demonstrated. However, attempts to produce OT lasing using lamda- variable reflectivity mirror coatings (to promote and suppress, simultaneously, the OT and FT mechanisms) were only marginally successful, even though major facility modifications were made to reduce cavity losses, suppress FT superradiance (ASE), suppress parasitic modes and increase pulse duration. Finally, CW OT lasing was demonstrated using the OT optical components in a combustion-driven, blowdown test facility. A specific energy level, sigma = 266 w/gm/sec, was inferred from the measurements. HF Chemical lasers, HF Overtone lasers, Pulsed photolytically initiated chemical lasers.
Download or read book Zero Power Gain Measurements in a CW HF Laser Using a Pulsed Probe Laser written by Richard A. Chodzko and published by . This book was released on 1973 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zero-power gain measurements in a supersonic diffusion-type CW HF laser are made using a pulse HF probe laser. A peak zero-power gain of 10% cm is measured on a P2(3) vibrational-rotational transition and 7% cm on a P1(6) transition for flow rates corresponding to 1.8 kW of closed-cavity power. The measured streamwise gain distributions of the P2(5) and P1(6) transistions were compared with the theory of King, et al., and the values of the peak gain agreed to within 50%. The variation of zero-power gain with rotational quantum number J fits a simple rotational equilibrium model indicating increasing rotational temperatures with increasing distance x from the nozzle exit plane. The model also indicates a total inversion for x = 0.2 in. for the P2(J) transitions and a partial inversion further downstream. The results indicate large amplitudes (about 50%) temporal-gain fluctuations in the active medium and the measured gain in a time-averaged value. (Author).
Download or read book Diode Laser Measurements of HF Concentrations Produced from Heptane Air Pan Fires Extinguished by FE 36 FM 200 FE 36 Plus APP and FM 200 Plus APP written by and published by . This book was released on 1998 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tunable diode laser absorption spectroscopy (TDLAS) is used to measure the time evolution of hydrogen fluoride (HF) concentrations produced from a series of enclosed heptane/air pan fires extinguished by FE-36, FM-200, FE-35 plus ammonium polyphosphate (APP), or FM-200 plus APP. For the fires studied, the change in HF gas concentration with time is dependent upon the fire fighting chemical used to extinguish the fire. The presence of APP is observed to reduce HF concentrations in the fire enclosure. Visible attenuation spectroscopy is also used to measure the amount of light attenuation (obscuration) that occurs as a hand held fire extinguisher containing powder firefighting agent is released in the crew space of a M1-Abrams land combat vehicle.
Download or read book Diode Laser Measurements of HF Concentrations From Heptane Air Pan Fires Extinguished by FE 36 and FE 36 Plus APP written by and published by . This book was released on 2000 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tunable diode laser absorption spectroscopy (TDLAS) is used to measure the time evolution of hydrogen fluoride (HF) concentrations produced from a series of enclosed heptane/air pan fires extinguished by FE-36 or FE-36 plus ammonium polyphosphate (APP). Recent advances in room temperature fiber coupled near infrared (NIR) diode lasers provide isolation of the laser and signal processing electronics from the hostile sampling site. For the fires studied, the change in HF gas concentration with time is dependent upon the fire fighting chemical used to extinguish the fire. The presence of APP is observed to accelerate the dissipation of HF from the fire enclosure. Visible attenuation spectroscopy is also used to measure the amount of light attenuation (obscuration) that occurs as a hand held fire extinguisher containing powder fire fighting agent is released in the crew space of a M1 Abrams land combat vehicle. Obscuration tests demonstrate that release of APP from extinguishers in an occupied space does not present a visibility challenge to the vehicle personnel.
Download or read book Diode Laser Measurements of HF Concentrations from Heptane Air Pan Fires Extinguished by FE 36 and FE 36 Plus Ammonium Polyphosphate written by and published by . This book was released on 1999 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tunable diode laser absorption spectroscopy is used to measure the time evolution of hydrogen fluoride concentrations produced from a series of enclosed heptane/air pan fires extinguished by FE-36 or FE-36 plus ammonium polyphosphate (APP). Recent advances in room temperature fiber coupled, near-infrared diode lasers provide isolation of the laser and signal processing electronics from the hostile sampling site. For the fires studied, the change in HF gas concentration with time is dependent upon the fire fighting chemical used to extinguish the fire. The presence of APP is observed to accelerate the dissipation of HF from the fire enclosure. Visible attenuation spectroscopy is also used to measure the amount of light attenuation (obscuration) that occurs as a hand held fire extinguisher containing powder fire fighting agent is released in the crew space of a M1-Abrams land combat vehicle. Obscuration tests demonstrate that release of APP from extinguishers in an occupied space does not present a visibility challenge to the vehicle personnel.
Download or read book Diode Laser Based Measurements of Hydrogen Fluoride Gas During Chemical Suppression of Fires written by Kevin McNesby and published by . This book was released on 1998 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Near-infrared tunable diode laser (NIR-TDL) spectroscopy is used to quantify hydrogen fluoride (HF) gas produced during fire-suppressant testing of Halon alternatives. Results of comparisons with other techniques for measuring HF gas concentrations are discussed. Measurements of HF gas produced in laboratory- and real-scale fire-suppression testing are presented. The necessity for time-resolved measurements during testing of suppression systems designed to scavenge HF gas is demonstrated.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Overtone Vibration laser Double Resonance Measurements of Vibrational Energy Transfer in HF and DF written by Karen Jane Rensberger and published by . This book was released on 1987 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diode Laser Measurements of HF Concentrations from Heptane Air Pan Fires Extinguished by FE 36 and FE 36 Plus Ammonium Polyphosphate written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tunable diode laser absorption spectroscopy is used to measure the time evolution of hydrogen fluoride concentrations produced from a series of enclosed heptane/air pan fires extinguished by FE-36 or FE-36 plus ammonium polyphosphate (APP). Recent advances in room temperature fiber coupled, near-infrared diode lasers provide isolation of the laser and signal processing electronics from the hostile sampling site. For the fires studied, the change in HF gas concentration with time is dependent upon the fire fighting chemical used to extinguish the fire. The presence of APP is observed to accelerate the dissipation of HF from the fire enclosure. Visible attenuation spectroscopy is also used to measure the amount of light attenuation (obscuration) that occurs as a hand held fire extinguisher containing powder fire fighting agent is released in the crew space of a M1-Abrams land combat vehicle. Obscuration tests demonstrate that release of APP from extinguishers in an occupied space does not present a visibility challenge to the vehicle personnel.
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Small Pulsed HF Chemical Laser written by C. R. Jones and published by . This book was released on 1972 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: A small pulsed hydrogen-fluoride chemical laser is described. The electrically pulsed device is to be used as a probe laser in the measurement of the optical gain of a continuous-wave HF laser. Various operating characteristics of the tunable laser which are important in gain measurements are described. (Author).
