Optical Measurements: Techniques and Applications (Hardcover, 2, Revised)

1 Introduction.- 2 The Schlieren Technique.- 2.1 Introduction.- 2.2 Basic Principle.- 2.3 Optical and Thermodynamic Interrelations.- 2.3.1 Refraction Index and Temperature Field.- 2.3.2 The Deflection of Light in an Inhomogeneous Medium.- 2.4 Application of the Schlieren Technique.- 2.4.1 Application to Transient Combustion Research.- The Schlieren Cinematography.- The Color Schlieren Technique.- 2.4.2 Application to Fuel-Injection Systems.- 3 Fundamentals of Holography and Interferometry.- 3.1 Abstract.- 3.2 Introduction.- 3.3 Principle of Holography.- 3.4 Simple Holographic Arrangement.- 3.5 Holographic Interferometry.- 3.5.1 Double Exposure Technique.- 3.5.2 Real-Time Method.- 3.5.3 Evaluation of the Interferograms.- 3.5.4 Finite Fringe Method.- 3.6 An Interference Method for Simultaneous Heat and Mass Transfer.- 3.7 Comparison with Classical Methods.- 4 Holographic Interferometry.- 4.1 Introduction.- 4.2 Components of a Holographic Interferometer.- 4.2.1 Light Source.- 4.2.2 Optical Table.- 4.2.3 Shutter.- 4.2.4 Beam Splitter.- 4.2.5 Attenuation Filter.- 4.2.6 Beam Expander.- 4.2.7 Mirrors, Lenses.- 4.2.8 Recording Materials.- 4.2.9 Piezo Mirror.- 4.2.10 Test Facility.- 4.3 Evaluation of Interferograms.- 4.3.1 Theoretical Principles.- 4.3.2 Conclusions.- 4.3.3 Calculation of Temperature and Concentration Distributions.- 4.3.4 Determination of the Local Heat Transfer Coefficient.- 4.4 Examples.- 4.4.1 Determination of the Temperature Distribution in a Compact Plate Heat Exchanger with Plain Fins.- Description of the Test Section.- Description of the Interferograms.- 5 Short Time Holography.- 5.1 Introduction.- 5.1.1 Historical development of holography.- 5.1.2 The holographic image.- 5.1.3 Holography as an optical measurement method.- 5.2 Elements of holography.- 5.2.1 Recording materials.- 5.2.2 The pulsed laser.- 5.2.3 Optical set-up.- 5.2.4 Adjusting the holographic camera.- 5.2.5 Recording, development and reconstruction of holograms.- Amplitude hologram.- Phase hologram.- 5.3 Application example: Dispersion characteristics in stirred bubble columns.- 5.3.1 Statement of the problem.- 5.3.2 Recording the holograms.- 5.3.3 Reconstruction and evaluation of the holograms.- 5.3.4 Stereo matching of the two holograms.- 5.3.5 Results.- 6 Evaluation of holograms by digital image processing.- 6.1 Introduction.- 6.1.1 Digitization of a picture.- 6.1.2 Gray value pictures.- 6.1.3 Operations with gray value images.- 6.2 A digital image processing system for the evaluation of holographic reconstructions.- 6.2.1 Evaluation of holographic images.- Scanning of in-line holograms.- Scanning of off-axis holograms.- 6.2.2 set-up of a digital image processing system.- 6.3 Image processing.- 6.3.1 Evaluation of single pulsed holograms.- 6.3.2 Evaluation of double pulsed holograms.- 6.3.3 Stereo matching algorithm.- 6.3.4 Accuracy.- 6.4 Evaluation of interferograms.- 7 Light Scattering.- 7.1 Introduction.- 7.2 Scattering Processes.- 7.2.1 Interaction of Light and Matter.- 7.2.2 Elastic Scattering.- 7.2.3 Inelastic Scattering.- 7.3 Light Scattering Techniques in Heat Transfer.- 7.3.1 Mie-Scattering.- 7.3.2 Rayleigh-Scattering.- 7.3.3 Raman-Scattering.- 7.3.4 Laser Induced Fluorescence (LIF).- 7.3.5 Absorption.- 7.4 Concluding Remarks.- 8 Laser?Doppler Velocimetry.- 8.1 Introduction.- 8.2 Principles of LDV.- 8.3 Optics.- 8.4 Signal Processing.- 8.5 Seeding Particles.- 8.6 Determination of Characteristic Turbulence-Quantities.- 8.6.1 Fundamentals of Turbulent Flows.- 8.6.2 Measurement of Turbulence-Quantities.- 9 Phase Doppler Anemometry (PDA).- 9.1 Introduction.- 9.2 General considerations for the application of PDA.- 9.3 Principles of PDA.- 9.3.1 Light-scattering by particles.- 9.3.2 Optical parameters of a Phase Doppler Measurement System.- 9.3.3 Phase-diameter relationship.- 9.4 Measurement accuracy.- 9.5 Applications of PDA.- 10 Dynamic Light Scattering.- 10.1 Introduction.- 10.2 Overview.- 10.3 Light Scattering Theory.- 10.3.1 Scattering Geometry and Assumptions.- 10.3.2 Temporal and Spatial Behavior of Scattered Light.- 10.3.3 Correlation Functions.- 10.3.4 Hydrodynamic Fluctuation Theory.- 10.4 Experimental Methods.- 10.4.1 Homodyne Method.- 10.4.2 Heterodyne Method.- 10.5 Measurement of Thermal Diffusivity.- 11 Raman Scattering.- 11.1 Introduction.- 11.2 Theoretical Basics of Raman Spectroscopy.- 11.2.1 Concentration Measurements.- 11.2.2 Temperature Measurement.- General Considerations.- Thermometry by Rotational Raman Spectroscopy.- Thermometry by Vibrational Raman Spectroscopy.- 11.3 Experimental set-up.- 11.3.1 Laser.- 11.3.2 Focussing and Collection Lenses.- 11.3.3 Spectral Frequency Selection.- 11.3.4 Photon Converters.- 11.3.5 Data Acquisition and Control.- 11.4 Selected Applications.- 11.5 Concluding Remarks.- 12 Laser induced Fluorescence.- 12.1 Introduction.- 12.2 Basic Principles of Laser Induced Fluorescence.- 12.2.1 General Considerations.- 12.2.2 Concentration Measurement.- 12.2.3 Temperature Measurement.- 12.2.4 Tracer LIF.- 12.3 Experimental Setup and Procedures.- 12.3.1 Experimental Setup.- 12.3.2 Experimental and Evaluation Procedures.- 12.4 Selected Applications.- 12.5 Concluding Remarks.- 13 Absorption.- 13.1 Introduction.- 13.2 Line spectra.- 13.2.1 Position.- 13.2.2 Shape and width.- A. Natural line broadening.- B. Doppler broadening.- C. Collisional broadening.- D. Voigt function-Mixed line shapes.- 13.2.3 Line strength.- 13.3 Experimental techniques.- 13.3.1 Overview.- Techniques used in absorption spectroscopy.- 13.3.2 Experimental examples.- A. In situ measurements of ammonia concentration in industrial combustion systems.- B.Fast temperature measurements with tunable diode lasers.- C. Harmonic detection techniques for the measurement of small absorptions.- D. Simultaneous -situ detection of oxygen and water in a full scale waste incinerator with near infrared diode lasers.- E. In situ determination of free radicals in flames.- 14 Pyrometry and Thermography.- 14.1 Introduction.- 14.2 Temperature Radiation.- 14.3 Method of Transmission.- 14.4 Radiation Receiver (Detector).- 14.5 Thermal Cameras ? Thermography Image Systems.- 14.6 Pyrometers.- 14.6.1 Classification According to Construction Types.- 14.6.2 Filament and Quotient Pyrometers.- 14.6.3 IR Recording Heads.- 14.7 Error Potential.- 14.7.1 Error Sources During Recording.- 14.7.2 Equipment Error.- 14.7.3 Problems with Thermograph Readings.- 14.8 Appendix.- 14.8.1 Important Constants.- 14.8.2 Further Information and Tables.- 15 Tomography.- 15.1 Introduction.- 15.2 Integral Measurement Methods.- 15.2.1 Absorption Methods.- 15.2.2 Interferometric Methods.- 15.3 Mathematical Reconstruction Methods.- 15.3.1 Algebraic Reconstruction Methods.- Matrix Methods.- Iterative Series Expansion.- 15.3.2 Explicit Reconstruction Methods.- Fourier Transform Method.- Analytical Solution of Integral Equations.- 15.3.3 Comparison of Reconstruction Methods.- 15.4 Implementations.- 15.4.1 Measurement of temperature fields in stirred vessels.- 15.4.2 Measurement of micro- and macromixing with the tomo-graphical dualwavelenght tomography.- 15.4.3 Tomographic measurements of flames with the Schlieren effect.- 15.4.4 Chemical species tomography by near infra-red absorption.- 16 Particle Image Velocimetry.- 16.1 Introduction.- 16.2 Hardware for the experimental set-up.- 16.3 Evaluation software.- 16.4 Three-dimensional flow.- 16.5 Applications.- Nomenclature.- References.