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Show an optical pyrometer to measure the total radiation output from surface burners. Sheridan [3] used a thermopile (Eppley Model) connected to a radiometer to measure the radiant output from a tube heater. Though these techniques are inexpensive, they do not provide a detailed spectrum of intensity versus wavelengths. Such a spectrum will indicate at which wavelength a load best absorbs heat and how much energy is available at various wavelengths. Also, it will help to match the burner emission to load absorption for optimum process efficiency. A system 2000 FfIR spectrometer provides such measurement capability and was acquired from Perkin Elmer for use in the present study. Solomon et al.[4] demonstrated the use of FfIR technique in the measurement of emission output and concentration of gaseous species in their coal combustion experiments. They validated the FfIR measurements with independent thermocouple measurements made at the same point. It should be noted that Kawaguchi et al. [5] employed a monochrometer (SR-5000 made by CI Co) to measure the emissive power from a heated mat. But the wavelength range employed in this monochrometer was only from 1.3 to 14.5 micrometers. System 2000 with a KBr detector provides us a wavelength range of about 1 to 25 micrometers. It can also be upgraded for any range of wavelength as necessary in the future. Further, System 2000 is versatile that it's use can be expanded and configured with a GC-IR interface, TG-IR interface, FfIR microscope, and NIR Ff -Raman accessory. PIR technology is implemented in various forms: tile, inconel screen, ceramic fiber, metallic fecraloy, and ceramic fabric. A porous ceramic flat plate tile, manufactured from Solamics Inc, MI, was selected for this work as most commonly used form. The schematic of the burner tile tested in this work is shown in Figure 2. An existing commercial deep fat fryer equipped with the flat plate tile was modified to allow in-situ radiation measurements on the burner surface via a view-port installed through the oil vat (see Figure 1). Water was used as the heat sink medium. System 2000 FfIR was positioned in-line with the view-port of the fryer and was employed to measure the spectral radiance of the burner. A blackbody with a temperature range of 50 to 1200 degree C (model IR-564 from Graseby Infrared) was used to calibrate the FTIR. The burner was replaced with the blackbody during calibration. A test matrix of gas composition was developed based on European standards for test gases. This matrix covers the complete range of gas compositions usually encounter in the United States. For ranges of distributed gas compositions in US (typical three component mixtures) and in Europe (typical two component mixtures), see Table 1 [7]. 1000/0 Methane was used as the baseline fuel. Three base limit gases, methane/propane (sooting), methane/hydrogen (lightback), and methane/nitrogen (flame lift), along with one propane-air peakshaving gas mixture were chosen to represent the full range gas supply variation. A fuel gas mixing station was designed and constructed to supply a continuous flow of repeatable, accurate fuel gas mixtures to the fryer during the fuel composition variability testing. This mixing station consisted of four rotometers wit.h di.fferent. flow. ran.ges connected in p.arallel to a mixing manifold. The details of the mixing statIo~ IS prOVIded In. FIgure 3. Th~ constltu~nts for the fuel mixtures, supplied by compressed gas cylInders, were mIxed together In the desIred volumetric ratios via the mixing station, and piped to the fryer for continuous operation. 4 |
