Effect of baffle structure on flow field characteristics of orbitally shaken bioreactor.

Disposable orbitally shaken bioreactors have been widely used for mammalian cell culture in suspension. Three kinds of baffle structures: vertical baffle, inclined baffle and horizontal baffle were designed in this work. The flow fields of the shaking bioreactor with different baffle structures were simulated, and the turbulence, dissolved oxygen and shear strain rate of the bioreactor were analyzed. The results showed that the quasi-steady-state flow patterns of the unbaffled shaking bioreactors were broken for the bioreactors with the strengthening effects of baffles. The mixing and the oxygen volumetric mass transfer coefficient (kLa) (simulated results) were improved significantly, and the shear strain rates were also increased greatly for the baffle bioreactors. The shear strain rates of the baffle bioreactors were mainly in the range of 0-20 s-1, and they were still low enough for CHO cell cultures.