Thermo-Mechanical Analysis of Lobe Type Root Blower

Abstract

The ultimate objective of manufacturing industries today is to conserve energy as much as possible. For achieving this objective, there is a continuous improvement in the product design as well as in manufacturing process. Now a days every industry wants to develop their product so that it can perform most efficient in all conditions. Most types of rotating machinery generate heat. The heat generated should be effectively dissipated in the atmosphere so that the machine can perform efficiently. The twin-lobe type blower consists of two lobe rotors and one gear pair as rotating element due to which the heat is generated in the blower. The heat propagates through the casing and outside covers. In order to expedite the heat removal from the blower, fins or extended surfaces are used. The objective of the present work is to optimize the casing and fin geometry for an effective heat dissipation thereby leading to an efficient blower performance and an increased life of the component. The heat transfer analysis of the blower housing is performed using ANSYS Transient Thermal. In the present study, different fin profiles were applied on the blower housing using different fin distribution patterns and analyzed for transient thermal performance to generate the temperature and heat flux reports. From the heat flux report, the heat dissipated by the fins was calculated and the heat dissipation calculated for optimum result to suggest improvement in the existing housing and fin geometry. The transient thermal analysis of various fin profile and distribution revel that the combination of annular fin of rectangular profile along with longitudinal fin of concave parabolic profile provides the most efficient heat dissipation for the analyzed housing. For the mechanical design aspects of the Twin-lobe blower, the GD2 (Flywheel Effect) and Moment of Inertia analysis was performed. For the performance of the blower, Speed-Temperature analysis was performed to plot the performance curve of Speed-discharge temperature.