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We study the mixing structure, mixing performance, and short term dynamics in round bottomed laminar tanks agitated by an eccentrically located angled disc. We define eccentricity (E 5 e/R) as the ratio of the distance of the axis of rota-tion from the center line of the tank (e) and the tank radius (R). The structural and dynamic features observed at differ-ent eccentricity values were compared using planar laser-induced fluorescence techniques and computational fluid dynamics calculations. A Poincar e analysis demonstrates the chaotic nature of the flow induced by eccentricity. Practi-cally globally chaotic conditions are observed for E 5 0.42 and E 5 0.50, with mixing times of 5–8 min at Re 5 416. We study the effect of different injection points on the short-term mixing dynamics and we calculate axial flow rates and Power numbers. Stirred tanks agitated by an eccentrically located angled disc are a simple and cost effective system for laminar mixing applications. V C 2013 American Institute of Chemical Engineers AIChE J, 59: 3092–3108, 2013