ANALYSIS OF A TAYLOR-POISEUILLE VORTEX FLOW REACTOR - I - FLOW PATTERNS AND MASS-TRANSFER CHARACTERISTICS

This paper shows the results of flow visualization and residence time distribution experiments in a Taylor-Poiseuille vortex flow apparatus. It is the first of a series that starts with the identification of fl ow patterns inside the device and goes up to the assessment of its per formance as an enzymatic reactor. Our approach is to study in path one single geometric configuration (radius ratio eta = 0.677 and aspect r atio Gamma = 18.30), adequate for use as a hetero geneous reactor and/ or adsorption system in bio-processes, rather than spanning a range of geometries and proposing empirical expressions for mass transport coe fficients. The range of rotations and axial flow rates used here corre spond to low/moderate rotational Reynolds numbers (Re-0 from 130 to 61 5, with 1.6 < Re-theta/Re-theta,Re-c < 7.7) and low axial ones (Re-ax from 0.172 to 1.067). An unusual behavior of the system was noted in t his operational region: the vortex drift velocities are less than one, and decrease continuously with increasing rotations, until a full sto p. Except for Re-theta close to the critical value, the downstream dis placement of vortices is slower than the mean axial velocity. The impl ications of this fact on the reactor performance are discussed. (C) 19 98 Elsevier Science Ltd. All rights reserved.