Download or read book Advanced Optical Diagnostics in High Speed Flows written by M. Samimy and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of High Speed Flows Using Advanced Optical Diagnostics written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few years, we have been working on the development of advanced optical diagnostics to be used in high speed flows. Our focus has been on the techniques based on molecular absorption filters. The focus of this report is on the details of a two-component planar measurement that we call Planar Doppler Velocimetry (PDV) technique. A PDV technique was developed and used to measure two components of instantaneous velocity in an ideally expanded, Mach 2, free jet. The technique utilizes a molecular filter as a frequency discriminator and uses two cameras to resolve two components of velocity on a plane that is illuminated by a laser sheet. Careful formation of the laser sheet, proper calibration of the splitter/recombiner imaging system and precise image registration were found to be critical steps in the technique. The velocity measurements obtained with this technique were compared with reference LDV measurements taken in the same flowfield. The mean velocity results were in very good agreement with the reference measurements and the turbulence results captured only the correct trend. A detailed error analysis describes the error sources inherent in the PDV technique. For the current two-component PDV system the estimated uncertainty for the mean velocity was better than +/-5%. Methods to improve the technique are discussed.
Download or read book Development and Application of Advanced Optical Diagnostics for the Study of High Speed Flows in Micro Systems written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary goal of this research program is the development and application of laser based flow diagnostics for the study of supersonic micro-nozzles, such as those, which might be employed for flow control and/or small satellite orbit maintenance. In this report we document the significant progress that has been made in FY-02 in the development of Molecular Tagging Velocimetry (MTV), including assessment of experimental accuracy at low (0.10 - 3 torr) static pressure and detailed comparisons between experimental flow field data and computational predictions using the Direct Simulation Monte Carlo (DSMC) method. Progress in the development of micro Planar Doppler Velocimetry (micro PDV) is also described.
Download or read book Optical Diagnostics for Flow Processes written by P. Buchhave and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: The origin of optical methods for fluid flow investigations appears to be nontraceable. This is no matter for surprise. After all seeing provides the most direct and common way for humans to learn about their environment. But at the same time some of the most sophisticated methods for doing measurements in fluids are also based on light and often laser light. A very large amount of material has been published in this area over the last two decades. Why then another publication? Well, the field is still in a state of rapid development. It is characterised by the use of results and methods developed within very different areas like optical physics, spectroscopy, communication systems, electronics and computer science, mechanical engineering, chemical engineering and, of course, fluid dynamics. We are not aware of a book containing both introductory and more advanced material that covers the same material as presented here. The book is the result of a compilation and expansion of material presented at a summer school on Optical Diagnosticsfor Flow Processes,held at RiS0 National Laboratory and the Technical University of Denmark in September 1993. The aim of the course was to provide a solid background for understanding, evaluating, and using modem optical diagnostic methods, addressing Ph. D. students and researchers active in areas of fluid flow research. The disciplines represented by the participants ranged from atmospheric fluid dynamics to biomedicine.
Download or read book Simultaneous High resolution Optical Wavefront and Flow Diagnostics for High speed Flows written by B. Thurow and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Optical and 3D Reconstruction Diagnostics for Combustion and Fluids Research written by Qian Wang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Imaging based optical diagnostics have played an important role in combustion and fluids studies. However, most imaging techniques are two dimensional. The increasing interest in accurate whole field measurement has heightened the need for developing three dimensional methods. Furthermore, many flows are inherently 3D in nature. One aim of this study is to develop an innovative 3D schlieren/shadowgraph system based on conventional schlieren/shadowgraph techniques. Furthermore, several research issues related to fluid mechanics and combustion are investigated using multi optical methods, including high speed direct/schlieren imaging, stereo imaging and 3D reconstruction and PIV techniques, etc. Firstly, a stereoscopic shadowgraph system has been developed using two sets of conventional z-type schlieren configurations. The test volume is set at the intersection of two inclined converging beams formed by two pairs of parabolic mirrors. Two synchronised high speed cameras are used to record the shadowgraph image pairs simultaneously. A precisely etched metal mesh plate is used to calibrate the stereoscopic shadowgraph system. The fully developed MATLAB code is employed to obtain calibration parameters and 3D coordinates reconstruction. A crystal block with internal 3D images is acted as a static model for point reconstruction. The 3D coordinates obtained are in good agreement with the real dimensions. The technique has been subsequently applied to investigate the bursting dynamics of a bubble. The 3D curve reconstruction is also accomplished successfully. The stereoscopic shadowgraph technique has been shown to be an effective method for both 3D visualisation and quantitative measurement. Secondly, the spark induced hot gas jet of a gas turbine combustor igniter has been investigated using optical methods with the combination of high speed schlieren and stereo imaging. A spherical shockwave and a hot gas jet are observed after spark initiation. The 3D velocity vectors of the flying off metal bits are calculated by a stereo imaging and reconstruction algorithm. It has been found that the amount and velocity distributions of the eroded metal bits are very different even at a fixed input voltage to the igniter, which contrasts with the quite consistent hot gas jet development. The 3D structures of the interaction boundaries between hot gas and ambient air are reconstructed for the first time using stereoscopic shadowgraph technique. Thirdly, the vortex dynamics and structures of methane-air diffusion flames are investigated under different co-flow conditions. The schlieren and PIV images show that the visible flame flickering is dominated by the dynamics of the external toroidal vortices outside. The co-flow air is observed to push the initiation point of toroidal vortices beyond the visible flame height and suppress flame flickering completely. The velocity vectors and vorticity contours at different air flow rates are presented and analysed. The shedding frequency of the toroidal vortex is found to be consistent with the result obtained from a photomultiplier. The investigation indicates that co-flow helps to depress flame instability by changing the vortex evolution. Finally, a laminar diffusion flame is studied under external acoustic excitation at different frequencies (6 Hz-100 Hz). The flame structures and vortex evolutions are investigated using high-speed stereo/schlieren imaging and digital imaging processing techniques. The flame frequency shows obvious nonlinear response to both the excitation frequency and amplitude. Several typical nonlinear phenomena were observed and analysed, which may serve as proof for relevant numerical simulation.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Student Training Program in Advanced Diagnostics for High speed Fluid Mechanics written by and published by . This book was released on 1995 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: As described in previous reports, this AASERT funding has provided support for graduate student training in high speed optical flow diagnostics. Funds were provided for the purchase of a 20 MHz rate framing camera (Hadland Imacon 792), which was used to capture a pair of rapidly sequenced Rayleigh scattering images, using a double pulsed Nd:YAG laser system purchased from parent grant AFOSR support. During the current reporting period, work has progressed on a synergistic program to develop a 'burst mode' laser system, which will, ultimately, provide the capability to obtain approximately 30 rapidly sequenced images. This work is closely coupled with the parent grant (#F4962O0-92-J-0217) and a collaborative AFOSR program with Profs. Alexander Smits and Garry Brown (F49620-93-1-0064).
Download or read book Advanced Diagnostics for Reacting Flows written by and published by . This book was released on 1990 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress is reported for the past year of an interdisciplinary program aimed at establishing advanced optical diagnostic techniques applicable to combustion gases and plasmas, with some emphasis on high speed flows. The primary flowfield parameters of interest are species concentrations (including electrons), temperature, mass density, pressure, and velocity, and quantities derivable from these parameters such as mass flow rate (from the product of density and velocity). The techniques under study are based on laser spectroscopy, particularly laser absorption and laser-induced fluorescence, with the latter capable of providing both single-point and multi-point (2-d and 3-d) measurements. Laser sources include tunable cw lasers (ring dye and semiconductor diode lasers) and tunable pulsed lasers (excimer-pumped dye and narrow-linewidth excimer). The cw lasers are spectrally narrow, allowing study of a new class of techniques based on spectral lineshapes and shifts, while the pulsed lasers provide intense bursts of photons needed for techniques based on light-scattering phenomena. Accomplishments of note include: the first optical measurement of mass flux in high speed air flows; the first applications of tunable semiconductor diode lasers to absorption and fluorescence measurements in high temperature plasmas and supersonic flows, and to the measurement of water vapor in high temperature combustion gases; the first application of the planar laser-induced fluorescence (PLIF) technique to nonequilibrium shock tunnel flows; and further advances in the development of shock tube diagnostics for rate constant measurements of elementary combustion reactions. Laser, Imaging, Combustion, Velocity, Pressure, Temperature, Fluorescence, Reacting, Flow, Plasma.
Download or read book Reactive Flow Visualization Through High speed Optical Laser Diagnostics written by Constandinos Miltiadis Mitsingas and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Optical Flow Cytometry written by Valery V. Tuchin and published by John Wiley & Sons. This book was released on 2011-03-31 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed look at the latest research in non-invasive in vivo cytometry and its applications, with particular emphasis on novel biophotonic methods, disease diagnosis, and monitoring of disease treatment at single cell level in stationary and flow conditions. This book thus covers the spectrum ranging from fundamental interactions between light, cells, vascular tissue, and cell labeling particles, to strategies and opportunities for preclinical and clinical research. General topics include light scattering by cells, fast video microscopy, polarization, laser-scanning, fluorescence, Raman, multi-photon, photothermal, and photoacoustic methods for cellular diagnostics and monitoring of disease treatment in living organisms. Also presented are discussions of advanced methods and techniques of classical flow cytometry.
Download or read book Optical Methods in Flow Particle Diagnostics written by and published by . This book was released on 1988 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Reacting Flows at High Speed written by and published by . This book was released on 2001 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of the research was to establish a strong foundation for understanding and predicting the interaction of fluid mechanical processes with chemical reactions in high speed flows. To accomplish this goal, expertise in chemical kinetics, experimental fluid mechanics and combustion, and computational fluid mechanics were brought together to make a systematic attack on turbulent reacting flows at high speed. In particular, the following tasks were established Task 1: High Speed Flow Experiments Including Mixing and Heat Release Task 2: Fundamental Combustion Experiments and Modeling Task 3: The Development and Application of Advanced Optical Diagnostics Task 4: Numerical Simulation Of Reacting Flows At High Speed The report summarizes the goals of the research and the progress made in each of these tasks.
Download or read book Optical Diagnostics of Gas dynamic Flows Using Advanced Laser Measurement Techniques written by Kenneth P. Gross and published by . This book was released on 1985 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 30th AIAA Fluid Dynamics Conference written by and published by . This book was released on 1999 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Immunological and Molecular Diagnosis of Infectious Disease written by Carel J. van Oss and published by CRC Press. This book was released on 1997-03-19 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by world-renowned experts, this book addresses immunological and molecular methodologies of diagnosis as well as clinical aspects of diseases. It book discusses DNA and RNA amplification methods, explains ELISA approaches, and introduces rapid diagnosis techniques, biosensors, and flow cytometry. The book examines bacterial and parasitic infections, including M. tuberculosis, Borrelia burgdorferi, Streptococcus pyogenes, chlamydia and schistosomes, and describe viral infections such as hantaviruses, hepatitis C., cytomegalovirus, herpes virus, and HIV. It also covers syndromes with infections origins, including prions, chronic fatigue syndrome, and superantigens, and much more.
Download or read book Annual Report 1989 90 written by New Brunswick. Department of Transportation and published by . This book was released on 1991 with total page 1272 pages. Available in PDF, EPUB and Kindle. Book excerpt: General activity review of associated branches and agencies to the Department which includes corporate securities registrations, a list of tenders received, and general financial data. Branches and agencies reviewed are responsible for motor vehicle activity, highway construction, traffic engineering, telecommunications and public utilities.
