Compressed air foam mixing device

A compressed air foam (CAF) mixing apparatus, comprising:

• (a) a source of a mixture of water and soap concentrate,
• (b) a source of pressurized air,
• (c) a mixing device including a body that presents a channel that extends from an inlet to an outlet, the inlet being in communication with the source of the mixture of water and soap concentrate and the outlet suitable for releasing pressurized foam resulting from the mixing of compressed air and the mixture of water and soap concentrate within the mixing device, the foam being for use by a firefighting apparatus, the channel of the mixing device including an inlet portion that is bounded by an outside wall, a venturi portion and a deceleration portion, the inlet portion extending between the inlet and the venturi portion and having a first cross sectional area, the venturi portion extending between the inlet portion and the deceleration portion, the venturi portion including a constricted zone having a second cross sectional area that is less than the first cross sectional area, the deceleration portion extending between the venturi portion and the outlet and having a third cross sectional area that is greater than the second cross sectional area, the mixing device further including at least one air conduit that is able to receive pressurized air from the source of pressurized air, the at least one air conduit including an air diffuser tube that enters through the outside wall of the inlet portion and extends though the center of constricted zone of the venturi portion and into the deceleration portion, the air diffuser tube terminating at a distal end thereof, the air diffuser tube presenting at least one aperture near the distal end thereof for injecting pressurized air into the deceleration portion, the at least one air conduit further including an air jacket arranged around the venturi portion, the air jacket in communication with the source of pressurized air and presenting first a pattern of apertures in communication with the deceleration portion for injecting pressurized air into the deceleration portion that are oriented in a diagonal fashion and a second a pattern of apertures in communication with the deceleration portion for injecting pressurized air into the deceleration portion that are oriented in a longitudinal fashion.