b'Engineer Innovation | MedicalA B CScaled Passive scalar Scaled Passive scalar Scaled Passive scalar0.0300.2240.4180.6120.8061.000 0.0300.2240.4180.6120.8061.000 0.0300.2240.4180.6120.8061.000Solution Time 201.471 (s) Rotation: 228.33 (rev) Solution Time 61.7445 (s) Rotation: 57.3194 (rev) Solution Time 100.085 (s) Rotation: 147.958 (rev)Figure 4: Comparing CFD simulations at full scale (at 95 percent volume uniformity) for each platform option, showing more homogeneous mixing in platform Bplatforms, increase the potential forYet another application involves the enhanced production yield and reducedetailed assessment of concentration time-to-market.vessel geometries: as product is concentrated in filtration applications, a One typical application of CFD instepped volume configuration (as bioreactors is evaluating impeller bladeillustrated in figure 5) is often used to designs for improving the blend time. Asmanage batch geometry. When a new illustrated in figures 1 and 2, ABECsproduct or process suggests the use of a approach is to validate the Simcentersmaller sump volume, the question STAR-CCM+ CFD model using resultsarises as to whether the sump volume from small-scale experiments withshould be modified, rather than impeller designs, then using thereplacing the entire tank. Changing to a validated CFD model to extrapolate thesmaller sump leads to a smaller mixer, results to full scale. which affects blend time, vortex formation, and short-circuiting (referring Another typical application involves theto the situation where recirculated flow evaluation of various bioreactorexits the tank quickly and is not well-production platforms for cell culture andblended with the sump contents). ABEC bacterial fermentationa critical firstuses Simcenter STAR-CCM+ simulations step in the production of biologicals. Theto generate detailed insights into the goal is to assess the suitability of eacheffects of geometry and mixer options platform for providing the sameon each of these characteristics. As environment for each organismillustrated in figures 6 and 7, simulations independent of scale. As illustrated inreveal details of the velocity vectors, flow figures 3 and 4, ABEC uses Simcenterstreamlines, particle tracks and even the STAR-CCM+ simulations to guide theair-water interface, leading to insights selection and determine which one bestabout the level of mixing, vortexFigure 5: Stepped volume configuration used suits the customers volume, geometry,formation and air entrainment resultingto manage batch geometry as product is environmental, production, schedulefrom any given sump volume and mixerconcentrated in filtration applicationsand economic constraints. combination. As an example, we demonstrated that we can cut blend time 50 percent by using laboratory tests to screen options and Simcenter STAR-CCM+ simulation to extend the results.Paul Kubera Vice President, Process Technology ABEC14'