A number of advanced optical diagnostic techniques are available to provide experimental data on oxy-coal flames to the CCMSC. These data will be compared to the simulation data to check for consistency as part of the V&V/UQ process. The techniques and their measurement capabilities are summarized in the following figures.

 

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Figure 1. Particle Shadow Velocimetry (PSV): Particles within the flame are illuminated by a strong light source. Their shadows are captured by the camera. Thus, this technique provides particle size, particle sphericity and an approximately planar particle velocity.

 

  Figure 2. Optical Infrared Emission: Radiation in the infrared spectrum is collected to yield the heat flux of the flame. Thus, this technique provides the line-of-sight, two-dimensional, infrared heat flux.
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Figure 3. CO2 Emission Pyrometry: An infrared filter captures radiation from the CO2 in the flame. Using an empirical correlation, the concentration of the CO2 yields the flame temperature. Thus, this technique provides the line-of-sight, two-dimensional CO2 concentration and flame temperature.

 

  Figure 4. Optical Flow Velocimetry (OFV). Changes in the intensity contours within flame images are used to track the velocity of the flame front. Thus, this technique provides the line-of-sight, two-dimensional velocity of the flame front.
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Figure 5. Narrow-band, Two-color Pyrometry: Intensity values from two wavelength bands (colors) are used to calculate flame temperature. Thus, this technique provides the line-of-sight, two-dimensional soot temperature and volume fraction. It can also measure the flame standoff distance depending on the reactor setup.   Figure 6. Particle Image Velocimetry (PIV): Particles (seed or coal) are illuminated by a laser sheet. Differences between two images yield the planar velocity. If the particles are sufficiently small, this velocity may be assumed to be the fluid velocity. Thus, this technique provides the two-dimensional, planar particle velocity.

 

Current Work

These techniques have been developed on a small, oxy-coal laboratory flame. Each technique, except for CO2 emission pyrometry, has also been performed on a bench-scale reactor. However, only particle shadow velocimetry and optical infrared emission have been performed on a pilot-scale reactor. In order to provide better data for the simulation comparison, our current work involves scaling up each measurement technique to provide high quality data at the pilot-scale.