Analyzing the Axial Flow of Swirl Effect in a Hybrid Rocket
From LARRY COVINGTON
The main objective of this research is to further address the difficulty of generating large thrust in a hybrid rocket by producing a swirl effect inside the fuel chamber. Theoretically, the solid fuel would burn more efficiently with a swirl effect than a traditional hybrid rocket. This would be caused by having swirl injectors in specific placements to allow the liquid oxidizer to swirl around the solid fuel in a cylindrical chamber. However, the boundary layer thickness of the velocity will cause the swirl velocity to slow down. Because of this, swirl injectors will need to be placed along the cylindrical chamber to keep the developed velocity constant along the axial distance. In this research, variations of swirl injector placements are analyzed along the axial distance of the cylindrical chamber. The axial distance of the swirl effect was calculated to determine if additional swirl injectors are required along the axial distance and the exact point they should be placed to maximize the swirl effect. The flow through the cylinder was modeled using Converge software for computational fluid dynamics [CFD] in the laminar flow regime. Swirl effect is the combination of the equations, swirl number (SN) and swirl angle (SA), which were used to validate the CFD models.