The effect of drag reducing agents on stenotic flow disturbances in dogs

Surgical procedures developed on a series of mongrel dogs, whereby a hot film anemometer probe was inserted in the left renal artery nearly flush with the wall of the descending aorta, have allowed measurements of aortic wall flow disturbance distal to an artificially created partial occlusion. Results show that the presence of a soluble drag reducing polymer (Separan AP 30) in the blood causes an increase in disturbance periodicity (or decrease in frequency) averaging 60% with polymer concentrations of ca. 62 ppm. The result is in substantial agreement with current theoretical developments which predict that drag reducing flow behavior may hinder, and in some cases prevent, the traumatic process of flow separation and reattachment. Application to current hemodynamic theories of atherogenesis suggests that reductions in local arterial wall disturbance levels may lead to a retardation in the development of atheroma.