ACCURACY OF PHASE-DOPPLER ANEMOMETRY IN THE PRESENCE OF FLAMES

The objectives of the present study were to clarify the influence of f lames on phase-Doppler anemometry (PDA) and to consider quantitatively the accuracy of measured sizes and velocities using a known-size poly styrene particle and a Bunsen burner placed in the optical path in PDA simulating the variation of refractive index in a combusting field. I t was found that fluctuations of a flame had some influence on the mea surement, especially on size, while the velocities obtained in these e xperiments showed little influence of the flame. Furthermore, a compen sation procedure for the error was discussed by comparing the scattere d data in size measurement with the displacement of incident laser bea ms. As a result, it was found that the displacement of the laser beams can be related to the degree of errors caused by the influence of a f lame on the optical path in PDA.