Analytical design of scroll rotor with varying tooth-wall thickness and its mechanical investigation concerning deformation and stress on the tooth wall

• An analytical design of the scroll rotor with variable tooth-wall thicknesses is established. • The variable base-circular involute and multi-segment arc correction are applied. • The deformation and stress analysis on the scroll tooth are performed using CFD methods. • The pressure-temperature near discharge increases, but stress and deformation remain safe. • The new scroll rotor has a smaller cladding volume, diameter, and compression ratio. The scroll rotor compressor is renowned for its efficiency, low vibration, reliability, and durability; however, it requires precise machining and assembly. Hence, studying the geometric design of the scroll rotor is essential to enhance its performance. This study presents an analytical method to optimize scroll rotor design with variable tooth-wall thicknesses, focusing on deformation and stress analysis. Using variable base-circular involute and multi-segment arc correction approaches, a 3D model was developed via a numerical approach and CAD software. The mechanical investigation was analyzed utilizing CFD methods. The results demonstrate that incorporating varying tooth-wall thicknesses into the design enhances efficiency and accuracy. While the modified design reduces the compression ratio, it compensates by minimizing cladding volume and chassis diameter. Consequently, the variable tooth thickness model is entirely practical for obtaining a more compact overall size of the desired scroll rotor. The thicker wall maintains safe stress and deformation levels despite increased pressure and temperature near the discharge port. This compact design achieves effective compression performance, making it suitable for medical oxygen equipment applications.