Gerotor oil pumps are widely used for the lubrication oil of an engine and the hydraulic source of an automatic transmission. Recently, improvements for the purposes of fuel efficiency and noise reduction have come to the forefront of the automobile industry, and it has become necessary to study the design of gerotors and ports. In this study, an expanded cardioid curve was developed, and an equation for a tooth profile with an expanded cardioid lobe shape has been suggested to reduce pump noise. The design was created using an automatic program; the program generated inner and outer rotor profiles and calculated performance parameters. Also, in order to decrease irregularity, CFD analyses were performed according to groove shapes in the exhaust port. Results showed the noise of the improved oil pump (the suggested gerotor [expanded cardioid] + the proposed port) was 5.44% lower than the existing oil pump (the existing gerotor [2-ellipse] + basic port).

Steam turbines of thermal power plants are installed in such a way that packing ring surrounds the entire turbine rotors in order to reduce the amount lost due to a leak of steam and to improve performance. However, the conventional packing ring cannot affect positively fluid velocity of the direction of steam, so it does not have the power to reduce vibration of the rotor. In this research, a study was conducted to reduce it by lowering the rotational speed of steam in the rotor. Anti-swirl teeth which changes rotational speed of steam into axial speed of it, designed in front of the conventional packing rings, and their numbers, twist angles. The characteristics of the rotor and the anti-swirl teeth were chosen as design factors to reduce vibration of the rotor. Through the finite element, the improved packing ring designed with the optimal anti-swirl teeth was developed.