Pre-Swirl Nozzle Carrier Inlet Geometry to Minimize Flow Separation

The inlet opening periphery is designed with specific convex and concave curvatures instead of sharp edges or simple rounded forms. The convex curvature region adjacent to the flow passage and the concave curvature region create a structured profile that guides flow smoothly into the passage, preventing separation while maintaining manufacturing feasibility through precise geometric definition.

The periphery of the inlet opening is given different curvature characteristics at different locations: a convex curvature in the region adjacent to the flow passage and a concave curvature in another region. This local differentiation of geometric properties optimizes flow attachment specifically where needed without unnecessarily complicating the entire structure.

Instead of using simple bevels or single-radius rounded edges, the invention employs a composite curvature profile with both convex and concave regions. This sophisticated curved geometry more effectively manages the flow transition into the passage, ensuring stable attachment and maximizing outlet velocity and swirl for improved cooling productivity.

The periphery geometry is defined by specific curvature parameters - the radius and orientation of the convex curvature region and the concave curvature region. By optimizing these geometric parameters, the flow attachment is enhanced beyond what simple bevels achieve, resulting in higher outlet velocity and swirl that directly improve cooling effectiveness.

The combination of convex and concave curvatures creates a more sophisticated flow guidance profile. The convex region ensures smooth entry, while the subsequent concave region helps maintain flow attachment downstream by creating a favorable pressure gradient, preventing separation that would occur with convex curvature alone.

The structured periphery with alternating convex and concave curvatures provides continuous flow guidance through the inlet region. This continuous geometric structuring maintains flow attachment stability throughout the entrance zone, not just at the immediate inlet, ensuring reliable flow progression through the entire passage.