Vibration Analysis & Weight Optimization of Impeller for Industrial Air Blower

MECHANICAL ENGINEERING

Abstract—This paper deals with the field complaint from the end user namely Eco-man Industries who are manufacturers of fertilizers. The problem indicated at their end for air blower were 1) Heavy corrosion on the impeller due to corrosive environment. 2) Though it complies with I.S.-1940 vibration norms, it creates unwanted irritating sound which can be termed as noise pollution. The root cause of noise pollution is vibration, which is the result of uneven mass distribution and can be termed as manufacturing defects. Secondly improper/inadequate clamping of the mating parts can result in vibrations. Vibrations are generally observed when a system or a element which is subjected to dynamic forces which can be periodic or random, linear or rotational .Vibrations are basically dependent on mass and the elasticity of the system which is also termed as stiffness. Vibration in any system is an indicator of malfunctioning of the system, though it is unavoidable can be kept within the permissible limits. It can result in wear and tear of the moving parts and a premature failure. Finally vibrations can be transmitted to the adjacent areas, to control the vibrations it is always advisable to control it, at the excitation source by providing devices like vibration dampers. Here we have used SS-304 as a substitute material for the impeller for improving the corrosion resistance. To counter balance the increase in material cost weight optimization is done. Our goal is to minimize the weight of the impeller which will result in low starting torque and material saving without altering the vibration characteristics of the impeller. Hence the objective of this study is to present Modal Analysis to find out the natural frequency of the impeller for five modes of vibration with variation in thickness in steps of 0.2mm from 2.0mm to 1.6mm and compare it with the excitation frequency for the safety of the design and avoid resonance. Modal analysis was performed on ansys software using finite element analysis technique. Note :- Below 1.6mm thickness welding becomes a problem, hence weight optimization was restricted to 1.6mm only.

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.