Abstract: An aircraft cabin pressure control system outflow valve includes a frame, a valve element, and a vortex generator structure. The vortex generator structure is coupled to the valve element and is rotatable therewith, and includes a plurality of first vortex generators and a plurality of second vortex generators. The first vortex generators spaced are apart from each other and are configured to generate first vortices when the valve element is in an open position and fluid flows through the flow passage. The second vortex generators are formed in each of the first vortex generators and are spaced apart from each other. The second vortex generators are each configured to generate second vortices, which are smaller than the first vortices, when the valve element is in an open position and fluid flows through the flow passage.

Abstract: An aircraft cabin pressure control system outflow valve includes a frame, a valve element, and a vortex generator structure. The vortex generator structure is coupled to the valve element and is rotatable therewith, and includes a plurality of first vortex generators and a plurality of second vortex generators. The first vortex generators spaced are apart from each other and are configured to generate first vortices when the valve element is in an open position and fluid flows through the flow passage. The second vortex generators are formed in each of the first vortex generators and are spaced apart from each other. The second vortex generators are each configured to generate second vortices, which are smaller than the first vortices, when the valve element is in an open position and fluid flows through the flow passage.

Abstract: A split flapper check valve includes one or more additional bushing/bearing surface areas for controlling check valve flapper position along the axis of the hinge pin. This is accomplished by adding one or more grounded bushings between the flappers. The one or more grounded bushings is/are non-rotationally coupled to the hinge pin, and thus grounded to the check valve housing, so that the flappers can bear against this additional surface. The additional bearing area has the effect of increasing the axial bearing surface area according to the number of additional ground lugs that are used, without increasing the diameter of the flapper lugs.