Deposition of Flowborne Materials on Vessel Walls

An air stream saturated with acetic acid vapor was blown through a tube made of agar which contained sodium hydroxide and phenolphthalein. Where flow was laminar, transfer of acid from the stream to the wall and decoloration of the indicator were of limited degree. Deposition of flowborne material was increased wherever the streamlines were disturbed, as at discontinuities and narrowings. Deposition was minimal slightly beyond the nozzle of the venturi tube, at the site where the momentum of the stream deviates it from the wall. These patterns of deposition by the stream are discussed in terms of their potential effects on the nutrition of the vessel wall, with particular reference to the localization of atheromatous and endocarditic lesions.