| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enhance the simulating precision of dust diffusion into the atmosphere. <P>SOLUTION: At least one fixedly installed camera 200 is used to continuously record the time series image of the smoke from the chimney present in a measuring target region at a definite time interval, the brightness in the time direction of the same pixel coordinates of the continuous image is subjected to Fourier transform to calculate the time series of the power spectrum of a screen, the power spectrum of an isotropic turbulent flow is calculated from the power spectrum of the screen, the vibration frequency caused by a Karman vortex is calculated from the difference between the power spectrum of the screen and the power spectrum of the isotropic turbulent flow. A Storrow-Hull number is calculated from the vibration frequency caused by the Karman vortex, wind velocity and the diameter of the chimney, a vortex diffusion coefficient and diffusion width are calculated using the relation between the Storrow-Hull number and a Reynolds number, the diffusion width is decomposed into a horizontal component and a vertical component using the image in the ejection direction of the smoke from the chimney and the diffusion of dust is simulated by the analysis of a numerical value using the horizontal component of the diffusion width, the vertical component of the diffusion width, a weather condition and a dust condition. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
