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Technology

When a door is open,the difference between the outside and inside temperatureleads to an exchange of air,resulting in cold air entering and warm heated air flowing out.An air curtain above or next to the open door provides separation of the two climates.Whilst developing the IndAC,Biddle has researched the outlet discharge pattern.The result is the Double Rectifier.

Fan offering air-engineering benefits

Patented Double Rectifier

The IndAC is equipped with radial backward curved fans which homogeneously distribute the air across the whole discharge opening,producing high efficiency and comfort levels.Another advantage is the low sound level of the fan.

Patented Double Rectifier

If a conventional industrial air curtain without a rectifier discharges air at the same rate as a unit with a Double Rectifier,the downward penetration is tangibly less (see Figure 1).The air stream does not reach the floor,and the open door is not screened off properly (see Figure 3).Consequences include draught and loss of heat. Due to the discharge pattern of an industrial air curtain with a Double Rectifier theincoming cold air is heated so that it is no longer experienced as draught.The Double Rectifier has vertical fins mounted on top of the horizontal fins to streamline the air flow in a better way,resulting in an excellent downward penetration (see Figure 2).The Double Rectifier,which minimises turbulence in the discharge air stream and surrounding air,ensures that the air movement generated by the fans, is directed downward in a deeply penetrating laminar air stream (see Figure 4). As a consequence the energy consumption is reduced and comfort levels are increased all year round.

Side view Front view Fig. 1 Fig. 2 Fig. 3 Industrial air curtain without rectifier IndAC with Double Rectifier Industrial air curtain without rectifier Fig. 4 IndAC with Double Rectifier

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