Download or read book Determination of Temperature and Concentration from Radiometric Measurements in Combustion Systems written by and published by . This book was released on 2001 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite that combustion diagnostics have reached high levels of refinement, it remains difficult to make quantitatively accurate nonintrusive measurements of temperature and species concentrations in realistic combustion environments. The goal of the present study is to develop nonintrusive spectral radiation tools to allow efficient high-fidelity determination of temperature and species concentrations in laminar and turbulent combustion systems. Temperature and concentrations are deduced from medium-to-coarse resolution measurements of spectral transmissivity and emitted intensity for homogeneous gas media, nonhomogeneous gas media and turbulent systems considering the turbulence radiation interaction (TRI). For a homogeneous gas medium, by minimizing the differences between measured and predicted transmissivity spectra, an inverse radiation model is developed to retrieve temperature and species concentrations simultaneously using the the Levenberg-Marquardt optimization method. This model has been validated by experimental measurements. The developed inverse radiation model is used to determine the optimal wavenumber range and resolution by retrieving temperature and species concentrations from a homogeneous gas column for a wide range of temperatures and concentrations. Multiple factors, including spectral region, spectral resolution, temperature and concentration range, and susceptibility to systematic error and random error have been considered. Results are obtained for homogeneous mixtures containing CO2, H2O or CO with N2. In nonhomogeneous gas media, transmissvities are not sensitive to temperature and concentration distributions, making it impossible to reconstruct temperature and species concentrations fields from transmissivity spectra. Another inverse calculation model is developed using measured line-of-sight emitted spectral intensity data to retrieve temperature profiles. Because intensity spectra are also not sensitive to concentration profiles, this model can only deduce the temperature profile together with an average concentration. Due to the ill-posedness of this inverse problem, additional conditions or criteria are needed to be imposed to determine the most realistic solution. Most regularization methods transform an ill-posed inverse problem into a well-behaved one by adding auxiliary information based on desired or assumed characteristics. Tikhonov regularization imposes smoothness to the solution by adding a regularization term. Tikhonov regularization has been shown to be suitable for solving these ill-posed problems, but it is difficult to select an appropriate regularization parameter, especially for nonlinear problems. A new regularization selection method based on the theory of the discrepancy principle and the L-curve criterion is proposed and shows good generality for different temperature profile inversions. Several types of temperature profiles are retrieved accurately using this method. For a turbulent system, the nonlinear interaction between turbulence and radiation has profound effects and cannot be neglected when developing inverse radiation tools. In the presence of TRI, temperature and concentration can never be measured directly. An inverse radiation model considering how turbulence and radiation interact along the detector's line-of-sight has been developed to deduce time-averaged and root-mean-square (rms) values of temperature and concentrations as well as the turbulent length scale from the time-averaged transmissivity and its rms spectrum for a single turbulent gas as well as a turbulent gas mixture.

Download or read book Radiometric Temperature Measurements written by and published by Academic Press. This book was released on 2009-11-18 with total page 479 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the practice of radiation thermometry, both at a primary level and for a variety of applications, such as in the materials processing industries and remote sensing. This book is written for those who will a) apply radiation thermometry in industrial practice b) use radiation thermometers for scientific research, c) the radiation thermometry specialist in a national measurement institute d) developers of radiation thermometers who are working to innovate products for instrument manufacturers and e) developers non-contact thermometry methods to address challenging thermometry problems. The author(s) of each chapter were chosen from a group of international scientists who are experts in the field and specialist(s) on the subject matter covered in the chapter. A large number of references are included at the end of each chapter as a resource for those seeking a deeper or more detailed understanding. This book is more than a practice guide. Readers will gain in-depth knowledge in: (1) the proper selection of the type of thermometer; (2) the best practice in using the radiation thermometers; (3) awareness of the error sources and subsequent appropriate procedure to reduce the overall uncertainty; and (4) understanding of the calibration chain and its current limitations. - Coverage of all fundamental aspects of the radiometric measurements - Coverage of practical applications with details on the instrumentation, calibration, and error sources - Authors are from the national labs internationally leading in R&D in temperature measurements - Comprehensive coverage with large number of references

Download or read book Radiometric Temperature Measurements written by and published by Academic Press. This book was released on 2009-10-01 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the theory of radiation thermometry, both at a primary level and for a variety of applications, such as in the materials processing industries and remote sensing. This book is written for those who will apply radiation thermometry in industrial practice; use radiation thermometers for scientific research; the radiation thermometry specialist in a national measurement institute; developers of radiation thermometers who are working to innovate products for instrument manufacturers, and developers of non-contact thermometry methods to address challenging thermometry problems. The authors of each chapter were chosen from a group of international scientists who are experts in the field and specialists on the subject matter covered in the chapter. A large number of references are included at the end of each chapter as a resource for those seeking a deeper or more detailed understanding. This book is more than a practice guide, readers will gain in-depth knowledge in: (1) the proper selection of the type of thermometer; (2) the best practice in using the radiation thermometers; (3) awareness of the error sources and subsequent appropriate procedure to reduce the overall uncertainty; and (4) understanding of the calibration chain and its current limitations. - Covers all fundamental aspects of the radiometric measurements - Discusses practical applications with details on the instrumentation, calibration, and error sources - Authors are from leading national labs working in R&D of temperature measurements

Download or read book Radiometric Temperature Measurements written by Zhuomin M.. Zhang and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Determination of Combustion Gas Temperatures by Infrared Radiometry in Sooting and Nonsooting Flames written by Valerie J. Lyons and published by . This book was released on 1989 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flame temperatures in nonsooting and sooting environments were successfully measured by radiometry for premixed propane oxygen laminar flames stabilized on a water cooled, porous sintered bronze burner. The measured temperatures in the nonsooting flames were compared with fine wire thermocouple measurements. The results show excellent agreement below 1700 K, and when the thermocouple measurements were corrected for radiation effects, the agreement was good for even higher temperatures. The benefits of radiometry are (1) the flow is not disturbed by an intruding probe, (2) calibration is easily done using a blackbody source, and (3) measurements can be made even with soot present. The theory involved in the radiometry measurements is discussed, as well as the energy balance calculations used to correct the thermocouple temperature measurements. (mjm).

Download or read book Determination of Combustion Gas Temperatures by Infrared Radiometry in Sooting and Nonsooting Flames written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-29 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flame temperatures in nonsooting and sooting environments were successfully measured by radiometry for pre-mixed propane-oxygen laminar flames stabilized on a water-cooled, porous sintered-bronze burner. The measured temperatures in the nonsooting flames were compared with fine-wire thermocouple measurements. The results show excellent agreement below 1700 K, and when the thermocouple measurements were corrected for radiation effects, the agreement was good for even higher temperatures. The benefits of radiometry are: (1) the flow is not disturbed by an intruding probe, (2) calibration is easily done using a blackbody source, and (3) measurements can be made even with soot present. The theory involved in the radiometry measurements and the energy balance calculations used to correct the thermocouple temperature measurements are discussed. Lyons, Valerie J. and Gracia-Salcedo, Carmen M. Glenn Research Center NASA-TP-2900, E-4446, NAS 1.60:2900, AVSCOM-TR-88-C-008, AD-A205373 DA PROJ. 1L1-61102-AH-45; RTOP 505-62-21...

Download or read book Radiometric Temperature Measurements written by Zhuomin M. Zhang and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Radiometric Errors on Accuracy of Temperature profile Measurement by Spectral Scanning Using Absorption emission Pyrometry written by Donald R. Buchele and published by . This book was released on 1972 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The spectral-scanning method may be used to determine the temperature profile of a jet- or rocket-engine exhaust stream by measurements of gas radiation and transmittance, at two or more wavelengths. A single, fixed line of sight is used, using immobile radiators outside of the gas stream, and there is no interference with the flow. At least two sets of measurements are made, each set consisting of the conventional three radiometric measurements of absorption-emission pyrometry, but each set is taken over a different spectral interval that gives different weight to the radiation from a different portion of the optical path. Thereby, discrimination is obtained with respect to location along the path. A given radiometric error causes an error in computed temperatures. The ratio between temperature error and radiometric error depends on profile shape, path length, temperature level, and strength of line absorption, and the absorption coefficient and its temperature dependency. These influence the choice of wavelengths, for any given gas. Conditions for minimum temperature error are derived. Numerical results are presented for a two-wavelength measurement on a family of profiles that may be expected in a practical case of hydrogen-oxygen combustion. Under favorable conditions, the fractional error in temperature approximates the fractional error in radiant-flux measurement.

Download or read book Optical Methods for the Measurement of the Temperature and Concentration Distribution in Combustion Chambers written by Liu Zhengbai and published by . This book was released on 1993 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Temperature and Species Concentration Measurements in Combustion Systems Using Timeresolved Dual broadband Pure Rotational Coherent Anti Stokes Raman Scattering RCARS written by Yi Gao and published by . This book was released on 2013 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Determination of Primary zone Smoke Concentrations from Spectral Radiance Measurements in Gas Turbine Combustors written by Carl T. Norgren and published by . This book was released on 1971 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: The smoke concentration within the primary zone of an experimental combustor operating at pressures up to 20 atmospheres was determined with a technique using spectral radiance measurements. Exhaust smoke concentration was obtained from reflectance readings of stained filter paper. The primary zone smoke concentration was of the order of 100 to 1000 times greater than at the exhaust. The smoke oxidation rate obtained is compared with reported values for coal particles and seeded laboratory flames. Primary zone smoke concentration was shown to be related to exhaust smoke number and total radiance.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992-06 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Precise Measurement of Heat of Combustion with a Bomb Calorimeter written by Ralph Slocomb Jessup and published by . This book was released on 1960 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Temperature and Concentration Measurements in an Internal Combustion Engine Using Laser Raman Spectroscopy written by Axel Otto zur Loye and published by . This book was released on 1983 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Radiometric Method for Determining Specific Heat at Elevated Temperatures written by C. P. Butler and published by . This book was released on 1958 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Evaluation of Radiometric Techniques for Measuring Temperature in Coal Gasifiers written by Gino J. Diloria and published by . This book was released on 1983 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fossil Energy Update written by and published by . This book was released on 1977 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: