The effect of large-scale roughness in promoting gas absorption

✍ Scribed by J.T. Davies; K.V. Warner

• Publisher: Elsevier Science
• Year: 1969
• Tongue: English
• Weight: 737 KB
• Volume: 24
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(69)80032-1

✦ Synopsis

The rate of absorption of CO, into water flowing over a plate on which there is large-scale roughness can be up to 3.5 times faster than into water over a smooth plate. The gas absorption is fastest when the roughness is of a form which induces "wake-interference" oscillations in the flowing water.

Results are compared with current theories: the Levich theory for isotropic turbulence predicts fairly well the observed variations of kL with Re and sin 0, but the measured kL figures are about ten times higher than the numerical values calculated. Evidently the surface renewal is much more effective than in isotropic turbulence.

Comparison of results for CO,, H, and He indicates that kL varies closely as the 0.5 power of molecular diffisivity.