Powder charging Faraday cage effect

In addition to the Faraday Cage effect, aerodynamic effects do not favor spraying inside a corner. Airflow considerations based on part geometry must also be taken into account to deliver the highly charged powder inside a corner or a channel, while not using so much air that the powder is prevented from depositing. 

Powder coatings have trouble penetrating deep depressions. The electric field lines do not penetrate into these tight areas and the charged powder can not penetrate and deposit there. This is observed in almost all ninety-degree comers and is commonly referred to as a Faraday Cage effect. While this effect can not be eliminated entirely, it is minimized by using triboelectric equipment. 

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