Banbury modeling

There have been several attempts at models incorporating breakup and coalescence. Two concepts underlie many of these models binary breakup and a flow subdivision into weak and strong flows. These ideas were first used by Manas-Zloczower, Nir, and Tadmor (1982,1984) in modeling the dispersion of carbon black in an elastomer in a Banbury internal mixer. A similar approach was taken by Janssen and Meijer (1995) to model blending of two polymers in an extruder. In this case the extruder was divided into two types of zones, strong and weak. The strong zones correspond to regions... 

Illustration Kinetics of dispersion the two-zone model. The models for agglomerate rupture when integrated with a flow model are useful for the modeling of dispersion in practical mixers, as was discussed for the case of drop dispersion. Manas-Zloczower, Nir, and Tadmor (1982), in an early study, presented a model for the dispersion of carbon black in rubber in a Banbury mixer (Fig. 34). The model is based on several simplifying assumptions Fragmentation is assumed to occur by rupture alone, and each rupture produces two equal-sized fragments. Rupture is assumed to occur... 

Fig. 34. Top Schematic view of a Ban ry Offo/n Evolution of the agglomerate size distribution with time predicted by the two-zone model with parameter values corresponding to the dispersion of carbon black in rubber in a Banbury muter. The size of an agglomerate after j ruptures is given by Dj — DQl2 i, where Do is the initial size of the agglomerates. The size of the aggregate (primary particle) corresponds to j = 28 (Manas-Zloczower, Nir, and Tadmor, 1982).

Reactive processing is limited to polymerization or chemical reactions of polymers in conventional singlescrew or twin-screw extruders, excluding processes in oscillatory kneaders, Banbury-type continuous mixers, or Diskpack equipment. Emphasis is placed on continuous processes that have been implemented commercially or that can serve as models for commercial purposes. 

Rousseau, R., Trembley, S. Breton, R. 2004. Defining and Modelling Situation Awareness A critical Review. In Banbury, S. and Tremblay (ed.),/l Cognitive Approach to Situation Awareness Theory and Application. Burlington VT Ashgate Publishing Company. 

Simulating Flows in the Banbury Mixer with Three-Dimensional Models 885... 

Compounds were mixed in a 4-minute, upside-down cycle Model B, Banbury 77 rpm 80°C at start cold water on full. The curative masterbatch and accelerators were added on the sheet-off mill. 

Using finite element techniqnes, a mathematical model was developed for the two-dimensional analysis of non-isothermal and transient flow and mixing of a generalised Newtonian fluid with an inert filler. The model could incorporate no-slip, partial-slip or perfect-slip wall conditions using a universally applicable numerical technique. The model was used to simulate the convection of carbon black with flowing rubber in the dispersive section of a tangential rotor (Banbury) mixer. The Carreau equation was used to model the rheological behaviour of the fluid in this example. 31 refs. 

The mixer was Moriyama internal mixer, model D3-75, with a 3 litre capacity. The fill factor was 0.7, and the rotor speeds were 72.2 rpm for the front rotor and 52.1 rpm for the back rotor. Also, a laboratory size Banbury mixer was used to assure the similarity of mixing performance. 

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