| 摘要 |
A method and apparatus are employed to detect the onset of soot or smoke formation in a flame exhaust. A pair of oppositely charged electrodes are placed in a flame located where soot formation is likely to occur. Varying voltages are applied across the electrodes and the limiting current, as the voltage is increased, called the saturation current, is measured. Generally, the saturation current decreases for higher fuel-to-air ratios in non-sooting flames. When the threshold for soot formation is approached, a definite saturation current is no longer observed and the current through the electrodes increases rapidly with increasing applied electrode voltage. The detection of the rapidly increasing current during sooting conditions is indicative of the formation of the soot itself. The method and apparatus can be employed to detect the onset of soot in various flames including, but not limited to, laminar premixed flames, laminar diffusion flames, turbulent premixed or diffusion flames, or otherwise generated high temperature gas flows. The method and apparatus can be employed in practical embodiments for the detection of the onset of soot formation in oil burners, gas burners and jet engines and the like.
|
