Polymer Drag Reduction and Bioluminescence Reduction

摘要

Drag reducing polymers interfere with the bursting process in turbulence by absorbing the energy like a shock absorber. The objective of this project was to test the effect of the polymer drag reducing agent polyethylene oxide (PEO) on bioluminescence stimulation in fully-characterized pipe flow. The well-documented reduction of turbulent skin friction by PEO was hypothesized to also result in a similar reduction of flow-stimulated bioluminescence. Drag reduction and bioluminescence suppression was assessed by comparing tests in turbulent flow with and without polymer, at equivalent flow speeds (Reynolds number). Treatment by 10 ppm PEO resulted in about 50-60% drag reduction, as expected, but showed no consistent evidence for a reduction in bioluminescence. Bioassays showed no evidence for any toxic effect of PEO on bioluminescence capacity or flow sensitivity. The lack of bioluminescence suppression due to polymer drag reduction in turbulent flow may be because cells are maximally stimulated in turbulent flow regardless of whether the polymer is present.