Computer aided curvature analysis along the contact line of conjugate helical surfaces

The fluid leakage across the contact line between two conjugate helical surfaces applied to fluid compression or pumping is the major concern in terms of the machine efficiency. A new quality index, the average comprehensive radius of curvature (ACRC), is proposed in this paper to characterize the geometrical shape of the leakage path. A numerical approach is accordingly developed for the comprehensive curvature analysis along the contact line. Numerical examples are provided at the end of the paper.