Turbulent diffusion in the core of a pipe with uniform transverse flow at the walls

✍ Scribed by S. K. Suneja; R. H. Shea; D. T. Wasan

• Publisher: American Institute of Chemical Engineers
• Year: 1972
• Tongue: English
• Weight: 741 KB
• Volume: 18
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690180136

✦ Synopsis

An onolysia of point source turbulent diffusion of o gaseous tracer in the core of o circulor straight porous pipe with uniform tronsverse flow ot the walls is presented. Time overoged concentrotion distributions were measured ot four distances downstream from a point source locoted a t the axis of o fully developed turbulent flow of air in o 6-in. pipe. Experiments were run at overage velocities between 4.36 and 23.0 ft./sec. (corresponding to Reynolds numbers 12, OOO to 66,000) with injection velocities ranging from 0 to 0.170 ft./sec. and suction velocities from 0 to 0.048 ft./sec. The highest injection rate corresponded to 58% by volume of the moin streom. Good agreement is obtained between the experiment01 and the colculoted concentrotion profiles.

The present study shows thot the plume width of the dispersing tracer is considerably affected by the transverse flow. It olso shows thot the eddy diffusivity in the pipe core ond the radial moss flux increose with fluid injection and decrease with suction through the pipe walls. Also, for increasing values of ospect ratio, they increose in the cose of injection and decreose in the cose of fluid suction.