High-frame-rate Planar Laser-induced Fluorescence Imaging of Diesel Sprays Using Pulse Burst Diagnostics

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ISBN 13 :
Total Pages : 71 pages
Book Rating : 4.:/5 (429 download)

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Book Synopsis High-frame-rate Planar Laser-induced Fluorescence Imaging of Diesel Sprays Using Pulse Burst Diagnostics by : Joseph P. Fuller

Download or read book High-frame-rate Planar Laser-induced Fluorescence Imaging of Diesel Sprays Using Pulse Burst Diagnostics written by Joseph P. Fuller and published by . This book was released on 2009 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Tracer-based Planar Laser-induced Fluorescence Diagnostics

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Author :
Publisher : Stanford University
ISBN 13 :
Total Pages : 197 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Tracer-based Planar Laser-induced Fluorescence Diagnostics by : Brian Ho-yin Cheung

Download or read book Tracer-based Planar Laser-induced Fluorescence Diagnostics written by Brian Ho-yin Cheung and published by Stanford University. This book was released on 2011 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two advances to tracer-based planar laser-induced fluorescence (PLIF) diagnostics are presented in this work. The first improvement is the development of a 3-pentanone fluorescence quantum yield (FQY) database and model for a wide range of conditions in support of quantitative PLIF diagnostics. In addition, this work presents a sensitive, time-resolved tracer-based PLIF diagnostic, accomplished by using a continuous-wave (CW) laser with the high-FQY tracer toluene. Because of its ease of use and desirable photophysical properties, PLIF diagnostics using 3-pentanone as a tracer are common, particularly for internal combustion engine (ICE) diagnostics. Thus, there is a need for 3-pentanone FQY measurements and modeling over a wide range of temperatures, pressures, and excitation wavelengths. For insight into the collisionless process in the FQY model, measurements were made in 3-pentanone vapor at low-pressures across a range of temperatures using a flowing cell. Laser excitation with 248, 266, 277, 308 nm wavelengths were utilized, and Rayleigh scattering of the laser beam was used to calibrate the optical efficiency of the collection optics and detector. This low-pressure data allows calculation of the 3-pentanone fluorescence rate and non-radiative de-excitation rate in the fluorescence model. The vibrational relaxation cascade parameter for 3-pentanone collisions was also determined. Measurements of 3-pentanone FQY were also made over a range of temperatures and pressures relevant to diagnostic applications, and, in particular, combined high-temperature and high-pressure conditions applicable to internal combustion engines (ICE). These data were collected in a custom-built optical cell capable of simultaneous high-pressure and high-temperature conditions. The behavior of the FQY in nitrogen for temperatures up to 745 K and in air up to 570 K was examined for pressures from 1 to 25 bar. These data were used to further optimize the parameters in the FQY model representing collisional processes. The large quantity of data with 308 nm excitation allowed optimization of the nitrogen quenching rate, and data in air were used to optimize the oxygen quenching rate. These data were also used to optimize the vibrational relaxation parameters for nitrogen and oxygen. The model with the updated parameters is consistent with the data collected in the current work, as well as with fluorescence measurements made in optical ICEs up to 1100 K and 28 bar. Another area of tracer-based PLIF diagnostics development is time-resolved imaging. Because PLIF diagnostics are often performed using pulsed lasers, the time resolution of measurements is limited to the pulse rate of laser. Use of a high-powered visible laser with an off-the-shelf cavity frequency doubler is shown to produce a moderate-power CW beam in the ultraviolet wavelength regime. Application of this CW source to excite toluene, a high-FQY tracer, yields a sensitive, time-resolved tracer-based PLIF diagnostic. Fluctuation detection limits for tracer mole fraction were investigated by applying the diagnostic to an atmospheric temperature and pressure nitrogen jet seeded with 4% toluene, and detection limits of better than 1% of the maximum toluene mole fraction were achieved for detection of fluorescence signal at a point, along a line, and over a plane. The diagnostic was also demonstrated on a turbulent jet for line and planar detection and demonstrated the potential for toluene time-resolved PLIF diagnostics with CW lasers.

Development of High Repetition Rate NO Planar Laser Induced Fluorescence Imaging

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ISBN 13 :
Total Pages : 168 pages
Book Rating : 4.:/5 (77 download)

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Book Synopsis Development of High Repetition Rate NO Planar Laser Induced Fluorescence Imaging by : Naibo Jiang

Download or read book Development of High Repetition Rate NO Planar Laser Induced Fluorescence Imaging written by Naibo Jiang and published by . This book was released on 2006 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This thesis has documented the development of a MHz repitition rate pulse burst laser system. Second harmonic and third harmonic efficiencies are improved by adding a Phase Conjugate Mirror to the system. Some high energy fundamental, second harmonic, and third harmonic burst sequences consisting of 1 - 12 pulses separated in time by between 4 and 12 microseconds are now routinely obtained. The reported burst envelopes are quite uniform. We have also demonstrated the ability to generate ultra-high frequency sequences of broadly wavelength tunable, high intensity laser pulses using a home built injection seeded Optical Parametric Oscillator (OPO), pumped by the second and third harmonic output of the pulse burst laser. Typical OPO output burst sequences consist of 6 - 10 pulses, separated in time by between 6 and 10 microseconds. With third harmonic pumping of the OPO system, we studied four conditions, two-crystal Singly Resonant OPO (SRO) cavity, three-crystal OPO cavity, single pass two-crystal Doubly Resonant OPO (DRO) cavity and double pass two-crystal OPO cavity. The double pass two-crystal OPO cavity gives the best operation in burst mode. For single pass OPO, the average total OPO conversion efficiency is approximately 25%. For double pass OPO, the average total OPO conversion efficiency is approximately 35%. We have also demonstrated injection seeding for OPO. The OPO output light linewidth is significantly narrowed. Some preliminary etalon traces are also reported. By mixing the OPO signal output at 622 nm with residual third harmonic at 355 nm, we obtained 226 nm burst sequences with average pulse energy of ~0.2 mJ. Injection seeding of the OPO increases the energy achieved by a factor of ~2. 226 nm burst sequences with reasonably uniform burst envelopes are reported. Using the system we have obtained, for the first time by any known optical method, Planar Laser Induced Fluorescence (PLIF) image sequences at ultrahigh (100kHz) frame rates, in particular NO PLIF image sequences, have been obtained in a Mach 2 jet.

Tracer-based Planar Laser-induced Fluorescence Diagnostics

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (718 download)

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Book Synopsis Tracer-based Planar Laser-induced Fluorescence Diagnostics by : Brian Ho-yin Cheung

Download or read book Tracer-based Planar Laser-induced Fluorescence Diagnostics written by Brian Ho-yin Cheung and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two advances to tracer-based planar laser-induced fluorescence (PLIF) diagnostics are presented in this work. The first improvement is the development of a 3-pentanone fluorescence quantum yield (FQY) database and model for a wide range of conditions in support of quantitative PLIF diagnostics. In addition, this work presents a sensitive, time-resolved tracer-based PLIF diagnostic, accomplished by using a continuous-wave (CW) laser with the high-FQY tracer toluene. Because of its ease of use and desirable photophysical properties, PLIF diagnostics using 3-pentanone as a tracer are common, particularly for internal combustion engine (ICE) diagnostics. Thus, there is a need for 3-pentanone FQY measurements and modeling over a wide range of temperatures, pressures, and excitation wavelengths. For insight into the collisionless process in the FQY model, measurements were made in 3-pentanone vapor at low-pressures across a range of temperatures using a flowing cell. Laser excitation with 248, 266, 277, 308 nm wavelengths were utilized, and Rayleigh scattering of the laser beam was used to calibrate the optical efficiency of the collection optics and detector. This low-pressure data allows calculation of the 3-pentanone fluorescence rate and non-radiative de-excitation rate in the fluorescence model. The vibrational relaxation cascade parameter for 3-pentanone collisions was also determined. Measurements of 3-pentanone FQY were also made over a range of temperatures and pressures relevant to diagnostic applications, and, in particular, combined high-temperature and high-pressure conditions applicable to internal combustion engines (ICE). These data were collected in a custom-built optical cell capable of simultaneous high-pressure and high-temperature conditions. The behavior of the FQY in nitrogen for temperatures up to 745 K and in air up to 570 K was examined for pressures from 1 to 25 bar. These data were used to further optimize the parameters in the FQY model representing collisional processes. The large quantity of data with 308 nm excitation allowed optimization of the nitrogen quenching rate, and data in air were used to optimize the oxygen quenching rate. These data were also used to optimize the vibrational relaxation parameters for nitrogen and oxygen. The model with the updated parameters is consistent with the data collected in the current work, as well as with fluorescence measurements made in optical ICEs up to 1100 K and 28 bar. Another area of tracer-based PLIF diagnostics development is time-resolved imaging. Because PLIF diagnostics are often performed using pulsed lasers, the time resolution of measurements is limited to the pulse rate of laser. Use of a high-powered visible laser with an off-the-shelf cavity frequency doubler is shown to produce a moderate-power CW beam in the ultraviolet wavelength regime. Application of this CW source to excite toluene, a high-FQY tracer, yields a sensitive, time-resolved tracer-based PLIF diagnostic. Fluctuation detection limits for tracer mole fraction were investigated by applying the diagnostic to an atmospheric temperature and pressure nitrogen jet seeded with 4% toluene, and detection limits of better than 1% of the maximum toluene mole fraction were achieved for detection of fluorescence signal at a point, along a line, and over a plane. The diagnostic was also demonstrated on a turbulent jet for line and planar detection and demonstrated the potential for toluene time-resolved PLIF diagnostics with CW lasers.

Planar Laser-induced Fluorescence Imaging of Flame Heat Release Rate

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Publisher :
ISBN 13 :
Total Pages : 21 pages
Book Rating : 4.:/5 (684 download)

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Book Synopsis Planar Laser-induced Fluorescence Imaging of Flame Heat Release Rate by :

Download or read book Planar Laser-induced Fluorescence Imaging of Flame Heat Release Rate written by and published by . This book was released on 1997 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Local heat release rate represents one of the most interesting experimental observables in the study of unsteady reacting flows. The direct measure of burning or heat release rate as a field variable is not possible. Numerous experimental investigations have relied on inferring this type of information as well as flame front topology from indirect measures which are presumed to be correlated. A recent study has brought into question many of the commonly used flame front marker and burning rate diagnostics. This same study found that the concentration of formyl radical offers the best possibility for measuring flame burning rate. However, primarily due to low concentrations, the fluorescence signal level from formyl is too weak to employ this diagnostic for single-pulse measurements of turbulent reacting flows. In this paper the authors describe and demonstrate a new fluorescence-based reaction front imaging diagnostic suitable for single-shot applications. The measurement is based on taking the pixel-by-pixel product of OH and CH2O planar laser-induced fluorescence images to yield an image closely related to a reaction rate. The spectroscopic and collisional processes affecting the measured signals are discussed and the foundation of the diagnostic, as based on laminar and unsteady flame calculations, is presented. The authors report the results of applying this diagnostic to the study of a laminar premixed flame subject to an interaction with an isolated line-vortex pair.

Strategies for Planar Laser-induced Fluorescence Thermometry in Shock Tube Flows

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Publisher : Stanford University
ISBN 13 :
Total Pages : 151 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Strategies for Planar Laser-induced Fluorescence Thermometry in Shock Tube Flows by : Ji Hyung Yoo

Download or read book Strategies for Planar Laser-induced Fluorescence Thermometry in Shock Tube Flows written by Ji Hyung Yoo and published by Stanford University. This book was released on 2011 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis was motivated by the need to better understand the temperature distribution in shock tube flows, especially in the near-wall flow regions. Two main ideas in planar laser-induced fluorescence (PLIF) diagnostics are explored in this thesis. The first topic is the development of a single-shot PLIF diagnostic technique for quantitative temperature distribution measurement in shock tube flow fields. PLIF is a non-intrusive, laser-based diagnostic technique capable of instantaneously imaging key flow features, such as temperature, pressure, density, and species concentration, by measuring fluorescence signal intensity from laser-excited tracer species. This study performed a comprehensive comparison of florescence tracers and excitation wavelengths to determine the optimal combination for PLIF imaging in shock tube flow applications. Excitation of toluene at 248nm wavelength was determined to be the optimal strategy due to the resulting high temperature sensitivity and fluorescence signal level, compared to other ketone and aromatic tracers at other excitation wavelengths. Sub-atmospheric toluene fluorescence yield data was measured to augment the existing photophysical data necessary for this diagnostic technique. In addition, a new imaging test section was built to allow PLIF imaging in all regions of the shock tube test section, including immediately adjacent to the side and end walls. The signal-to-noise (SNR) and spatial resolution of the PLIF images were optimized using statistical analysis. Temperature field measurements were made with the PLIF diagnostic technique across normal incident and reflected shocks in the shock tube core flow. The resulting images show uniform spatial distribution, and good agreement with conditions calculated from the normal shock jump equations. Temperature measurement uncertainty is about 3.6% at 800K. The diagnostic was also applied to image flow over a wedge. The resulting images capture all the flow features predicted by numerical simulations. The second topic is the development of a quantitative near-wall diagnostic using tracer-based PLIF imaging. Side wall thermal boundary layers and end wall thermal layers are imaged to study the temperature distribution present under constant pressure conditions. The diagnostic technique validated in the shock tube core flow region was further optimized to improve near-wall image quality. The optimization process considered various wall materials, laser sheet orientations, camera collection angles, and optical components to find the configuration that provides the best images. The resulting images have increased resolution (15[Mu]m) and are able to resolve very thin non-uniform near-wall temperature layers (down to 60[Mu]m from the surface). The temperature field and thickness measurements of near-wall shock tube flows under various shock conditions and test gases showed good agreement with boundary layer theory. To conclude this thesis, new applications and future improvements to the developed PLIF diagnostic technique are discussed. These suggested refinements can provide an even more robust and versatile PLIF imaging technique capable of measuring a wider range of flow conditions near walls.

Applications of Planar Laser-induced Fluorescence Imaging Diagnostics to Reacting Flows

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Publisher :
ISBN 13 :
Total Pages : 21 pages
Book Rating : 4.:/5 (977 download)

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Book Synopsis Applications of Planar Laser-induced Fluorescence Imaging Diagnostics to Reacting Flows by : P. H. Paul

Download or read book Applications of Planar Laser-induced Fluorescence Imaging Diagnostics to Reacting Flows written by P. H. Paul and published by . This book was released on 1990 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Laser Diagnostics for Reacting Flows

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Publisher :
ISBN 13 :
Total Pages : 72 pages
Book Rating : 4.:/5 (227 download)

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Book Synopsis Laser Diagnostics for Reacting Flows by :

Download or read book Laser Diagnostics for Reacting Flows written by and published by . This book was released on 2007 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced optical diagnostic techniques relevant to propulsion were investigated. The techniques studied were based on laser spectroscopy, with emphasis on spectrally-resolved absorption and laser-induced fluorescence (LIF). Laser sources included tunable cw near-infrared diode lasers and tunable (or fixed-wavelength) pulsed lasers operated at ultraviolet (UV) or infrared (IR) wavelengths. The cw lasers were spectrally narrow, allowing study of innovative diagnostics based on spectral lineshapes, while the pulsed lasers provided intense bursts of photons needed for techniques based on LIF. Accomplishments of note included: (1) development of a new imaging diagnostic based on infrared planar laser-induced fluorescence (IR PLIF), (2) investigations of quantitative ultraviolet (UV) PLIF of NO and CO2 in high-pressure combustion environments, (3) the development of a new temperature diagnostic using UV absorption of CO2 for high-temperature combustion environments, (4) development of advanced wavelength-multiplexed diode laser absorption sensing of non-uniform temperature distributions, gas temperature in scramjet flows, and tunable mid-IR-based fuel sensing, and (5) further development of quantitative tracers to image fuel distribution using ketones and the aromatic toluene. The full spectrum of results was published in thirty-eight papers in the AIAA and peer reviewed literature, seven PhD theses, and forty-three presentations and invited lectures.

Quantitative Planar Laser-induced Fluorescence Imaging of Radical Species in High Pressure Flames

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Quantitative Planar Laser-induced Fluorescence Imaging of Radical Species in High Pressure Flames by : B. E. Battles

Download or read book Quantitative Planar Laser-induced Fluorescence Imaging of Radical Species in High Pressure Flames written by B. E. Battles and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Development and Application of Infrared and Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics

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Publisher :
ISBN 13 : 9780549356424
Total Pages : 318 pages
Book Rating : 4.3/5 (564 download)

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Book Synopsis Development and Application of Infrared and Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics by : David A. Rothamer

Download or read book Development and Application of Infrared and Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics written by David A. Rothamer and published by . This book was released on 2007 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: IR-PLIF measurements of temperature and pressure are a new application of the technique. Initial IR-PLIF measurements focused on species concentrations of CO and CO2. The strong dependence of IR-PLIF signals on temperature and pressure indicated that IR-PLIF measurements of those quantities are possible.

Oh Planar Laser Induced Fluorescence Measurements for the Study of High Pressure Flames

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Author :
Publisher : BiblioGov
ISBN 13 : 9781289167400
Total Pages : 24 pages
Book Rating : 4.1/5 (674 download)

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Book Synopsis Oh Planar Laser Induced Fluorescence Measurements for the Study of High Pressure Flames by : Nasa Technical Reports Server (Ntrs)

Download or read book Oh Planar Laser Induced Fluorescence Measurements for the Study of High Pressure Flames written by Nasa Technical Reports Server (Ntrs) and published by BiblioGov. This book was released on 2013-07 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Planar laser induced fluorescence (PLIF) is used by the Combustion Branch at the NASA Glenn Research Center (NASA Glenn) to assess the characteristics of the flowfield produced by aircraft fuel injectors. To improve and expand the capabilities of the PLIF system new equipment was installed. The new capabilities of the modified PLIF system are assessed by collecting OH PLIF in a methane/air flame produced by a flat flame burner. Specifically, the modifications characterized are the addition of an injection seeder to a Nd: YAG laser pumping an optical parametric oscillator (OPO) and the use of a new camera with an interline CCD. OH fluorescence results using the injection seeded OPO laser are compared to results using a Nd: YAG pumped dye laser with ultraviolet extender (UVX). Best settings of the new camera for maximum detection of PLIF signal are reported for the controller gain and microchannel plate (MCP) bracket pulsing. Results are also reported from tests of the Dual Image Feature (DIF) mode of the new camera which allows image pairs to be acquired in rapid succession. This allows acquisition of a PLIF image and a background signal almost simultaneously. Saturation effects in the new camera were also investigated and are reporte

Development and Application of Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics for HCCI Engines

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (712 download)

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Book Synopsis Development and Application of Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics for HCCI Engines by : Jordan Andrew Snyder

Download or read book Development and Application of Tracer-based Planar Laser-induced Fluorescence Imaging Diagnostics for HCCI Engines written by Jordan Andrew Snyder and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Homogeneous charge compression ignition (HCCI) is an emerging engine strategy that can provide both high efficiency and low emissions, particularly in terms of NOx and soot. An important challenge of HCCI is the inherent narrow load range, bounded by combustion instability and misfires at low-load, and high pressure rise- rate (PRR) at high-load. In response, researchers have devised a number of strategies to expand the limits of HCCI operation. Negative valve overlap (NVO) with pilot injection can extend the low-load gasoline HCCI operating limit by increasing sensible energy during main compression through hot residual gas retention. Chemical effects due to reformation of the pilot injection may further impact combustion. Similarly, the high-load limit can be extended by increasing naturally occurring thermal stratification (TS) of the in- cylinder charge. These non-uniformities result in sequential auto-ignition that can effectively lower the PRR and thus expand the high-load limit. While demonstrations of these strategies have been successful and multiple engine studies have been completed, further characterization of key processes such as residual gas mixing and TS development is needed. This motivates the development of quantitative imaging diagnostics to improve the understanding of these complicated processes. In this study, tracer-based planar laser-induced fluorescence (PLIF) diagnostics for temperature and composition have been refined and optimized for application in HCCI engines at both load extremes. Acetone and 3-pentanone (both ketones) have been selected as seeded PLIF tracers as they provide good overall sensitivity and performance. Single-line and two-line diagnostic variations have been investigated, with an emphasis on optimizing overall diagnostic performance through excitation wavelength selection. Based on a detailed uncertainty analysis excitation wavelengths of 277 nm and 308 nm were selected for subsequent studies. Resulting single-shot temperature precisions were typically on the order 4 K and 12 K for the single-line and two-line techniques respectively. The corresponding mole fraction precision for the two-line technique was typically 4-5%. These results are consistent with the uncertainty analysis and demonstrate the utility of the optimization. HCCI studies were performed in two optically accessible engines, each configured for a specific load extreme. Residual mixing for low-load HCCI operation with NVO was first studied using the two-line technique to provide the simultaneous temperature and composition distribution. These measurements indicated rapid mixing of retained residuals during gas exchange and early compression, reaching a steady-state value midway through compression. Temperature stratification gradually increased throughout the remainder of compression while compositional stratification effectively remained constant. Variation of operating parameters such as main and NVO injection timing exhibited minimal differences in thermal or compositional stratification during main compression. Measurement during NVO recompression and re-expansion were also acquired to assess the in-cylinder temperatures stratification prior to chemical reaction and gas exchange. Next the development of thermal stratification for high-load HCCI with conventional valve timing was investigated using the single-line technique. These studies indicated a progressive increase in TS during compression, reaching a maximum standard deviation of 10 K at top dead center. Comparison of results for motored and fired operation exhibited similar trends. This finding indicates that the mechanism producing the TS is the same for both cases, although some differences in magnitude can occur. A subsequent parametric study proved that these differences can be attributed to the impact of both incomplete fuel mixing and cylinder-wall temperature variation, depending on the type of engine operation (DI skipfiring or premixed continuous firing). All measurements demonstrate the feasibility of quantitative tracer-based PLIF diagnostics in harsh engine environments and provide useful information for future HCCI engine development.

Oh Planar Laser Induced Fluorescence (Plif) Measurements for the Study of High Pressure Flames: An Evaluation of a New Laser and a New Camera System

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Author :
Publisher : Independently Published
ISBN 13 : 9781794369306
Total Pages : 24 pages
Book Rating : 4.3/5 (693 download)

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Book Synopsis Oh Planar Laser Induced Fluorescence (Plif) Measurements for the Study of High Pressure Flames: An Evaluation of a New Laser and a New Camera System by : National Aeronautics and Space Adm Nasa

Download or read book Oh Planar Laser Induced Fluorescence (Plif) Measurements for the Study of High Pressure Flames: An Evaluation of a New Laser and a New Camera System written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-19 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Planar laser induced fluorescence (PLIF) is used by the Combustion Branch at the NASA Glenn Research Center (NASA Glenn) to assess the characteristics of the flowfield produced by aircraft fuel injectors. To improve and expand the capabilities of the PLIF system new equipment was installed. The new capabilities of the modified PLIF system are assessed by collecting OH PLIF in a methane/air flame produced by a flat flame burner. Specifically, the modifications characterized are the addition of an injection seeder to a Nd: YAG laser pumping an optical parametric oscillator (OPO) and the use of a new camera with an interline CCD. OH fluorescence results using the injection seeded OPO laser are compared to results using a Nd: YAG pumped dye laser with ultraviolet extender (UVX). Best settings of the new camera for maximum detection of PLIF signal are reported for the controller gain and microchannel plate (MCP) bracket pulsing. Results are also reported from tests of the Dual Image Feature (DIF) mode of the new camera which allows image pairs to be acquired in rapid succession. This allows acquisition of a PLIF image and a background signal almost simultaneously. Saturation effects in the new camera were also investigated and are reported. Tedder, Sarah and Hicks, Yolanda Glenn Research Center NASA/TM-2012-217614, E-182

Development of a Diagonal Excitation/observation Diagnostic Technique for Planar Laser-induced Fluorescence of the Methyne Radical in Diesel Engines

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Publisher :
ISBN 13 :
Total Pages : 516 pages
Book Rating : 4.:/5 (89 download)

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Book Synopsis Development of a Diagonal Excitation/observation Diagnostic Technique for Planar Laser-induced Fluorescence of the Methyne Radical in Diesel Engines by : Mark P. Musculus

Download or read book Development of a Diagonal Excitation/observation Diagnostic Technique for Planar Laser-induced Fluorescence of the Methyne Radical in Diesel Engines written by Mark P. Musculus and published by . This book was released on 1998 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Single Pulse Planar Laser Induced Fluorescence Imaging of Hydroxyl Radicals in a Spark Ignition Engine

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Publisher :
ISBN 13 :
Total Pages : 11 pages
Book Rating : 4.:/5 (617 download)

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Book Synopsis Single Pulse Planar Laser Induced Fluorescence Imaging of Hydroxyl Radicals in a Spark Ignition Engine by : Ali Serpengüzel

Download or read book Single Pulse Planar Laser Induced Fluorescence Imaging of Hydroxyl Radicals in a Spark Ignition Engine written by Ali Serpengüzel and published by . This book was released on 1993 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Laser-induced Fluorescence for Medical Diagnostics

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Publisher :
ISBN 13 :
Total Pages : 324 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Laser-induced Fluorescence for Medical Diagnostics by : Stefan Andersson-Engels

Download or read book Laser-induced Fluorescence for Medical Diagnostics written by Stefan Andersson-Engels and published by . This book was released on 1989 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Advanced Diagnostics for Reacting Flows

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Publisher :
ISBN 13 :
Total Pages : 81 pages
Book Rating : 4.:/5 (227 download)

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Book Synopsis Advanced Diagnostics for Reacting Flows by : R. K. Hanson

Download or read book Advanced Diagnostics for Reacting Flows written by R. K. Hanson and published by . This book was released on 1983 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress is reported for the third year of an interdisciplinary program to innovate modern diagnostic techniques for application to reacting flows. Project areas are: (1) fiber optic absorption/fluorescence probes for species measurements employing tunable ultraviolet, visable and infrared laser sources; (2)wavelength modulation spectroscopy, using rapid-scanning ultraviolet, visible and infrared laser sources, for measurements of species, temperature and absorption lineshapes, (3) quantitative flow visualization, including temporally and spatially resolved species measurements in a plane, using laser-induced fluorescence; (4) multiple-point velocity visualization; (5) plasma diagnostics, utilizing planar laser-induced fluorescence and wavelength modulation techniques; (6) diagnostic techniques for thermionic converter plasmas; (7) application of advanced diagnostic techniques for studies of turbulent reacting flows; (8) development of measurement techniques and a novel facility for investigations of droplet evaporation in turbulent flows; (9) holographic display techniques for 3-D visualization of flowfield data; (10) coherent anti-Stokes Raman spectroscopy (CARS) for temperature and velocity measurements in a supersonic jet; and (11) computed absorption tomography system for species measurements in a plane.