EVALUATING THE ROLE OF GEOMETRICAL FEATURES OF A TAYLOR VORTEX BIOREACTOR TO CULTURE ANIMAL CELLS BY USING COMPUTATIONAL FLUID DYNAMICS

Abstract : Taylor bioreactor is fast becoming the next bioreactor to culture animal cells due to milder shear and homogenous flow structures throughout the bioreactor in comparison to the traditional stirred tank. However, there is not much information in the literature about how geometrical aspects of the Taylor bioreactor may affect the culture of animal cells which could result in poor efficiency. As a result, six different geometrical conditions of Taylor bioreactor are presented, related to off-bottom clearance and the external cylinders' bottom shape, after conducting a detailed grid and time-step independence study and validating with experimental results. Simulations were conducted at Reynolds number of 12077 and Taylor number of 5331 with a radius ratio of 0.84 and aspect ratio of 19.8. Throughout the bulk zone equivalent of 80 % of the gap-width, the mean velocity was found to be around 50 % of the maximum with similar gradients which is encouraging for cultivating of animal cells in Taylor bioreactor in comparison with spinner flask and stirred tank bioreactors where the gradients are much less uniform. Curved bottom surfaces of the external cylinder and higher off-bottom clearance areas adversely affect the flow structures creating dead-zone areas in the off-bottom clearance area.