Baffle (heat transfer)

Baffles (also baffles ) are superior to the stirred tank components which prevent the entire Rührinhalt the boiler - due to the inertia of the medium - with the stirrer rotates along. They are used in technical mix of fabrics.

Function

Baffles are flow-disrupting internals in stirred tanks. They prevent the co-rotation of the moving through the central agitator fluid in the stirred tank ( see also the below linked video of a reinforced and an unreinforced stirred tank ). They are installed on the container wall or in stirred tanks enamelled, by a nozzle at the upper floor of the apparatus.

They allow for low viscous liquids only the mixing. For high viscosity liquids, however, the baffle is not useful, but leads to the flow shadow and imperfect mixing.

Designs

  • In non-coated Rührwerksapparaten ( eg those made ​​of stainless steel ), baffles are welded to the tank wall and consist essentially of, welded to the tank wall or screwed, flat iron. Optimally, four such flat bar at an angle of 90 ° to each other mounted on the Bewälterwand. The width of such a baffle is about 0.1 to 0.12 x vessel diameter.
  • In enameled apparatuses there are various designs of baffles, which always correspond to a profiled tubular mounting portion substantially. The profile of the tube ( cross section ) depends on installation conditions or vendor- specific: Cylindrical Baffles: The pipe profile corresponds to a circle. This design is only used when fittings are present in the interior of the baffle, which require a correspondingly large amount of space.
  • Paddle baffles: The pipe profile corresponds to an oval in cross section.
  • C baffles Pfaudler Werke: The profile of the insert corresponding to the shape of a "C ", the concave side of the C is flown
  • Delta baffles the company THALETEC ( EHW Thale ): The profile of the insert corresponds to an isosceles triangle with an alternative which can be aligned in the flow direction "sharp " or "flat" side of the baffle.
  • Examples of different baffle

Enamelled paddle baffles for glass-lined Reactors

Enamelled stirred vessel with 3-speed stirrer and baffles ( tubular fitting right shown in section )

Delta baffles with a triangular profile

Mixing (process engineering)
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