International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 09 | Sep -2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1 Design and Analysis of Compressor Impeller using New Aluminium Alloy Material. Mr. Sunil Gund 1 , Prof. P.P. Ritapure 2 1PG Scholar, Dept. of Mechanical Engineering, ZES 'Zeal College of engineering & Research, Pune, Maharashtra, India. 2Professor, Dept. of Mechanical Engineering, ZES 'Zeal College of engineering & Research, Pune, Maharashtra, India. ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - Since the centrifugal compressors have a wide range of applications, the reliability of impellers as the vital components should be ensured. Due to the complicated operating conditions and various Gas compositions and its corrosive and non-corrosive nature, it is important to do Finite Element Analysis (FEA) on Impeller with alternate material for its feasibility. During the operation of centrifugal compressor, failure easily occurs in the presence of stresses, cyclic loads, vibrations, corrosion. The failure process characterizes with strong nonlinearity and hence it is difficult to be described by conventional methods. On this background aim of this research was to manufacture a new Aluminium alloy Impeller in order to improve the life of an impeller. In this project, Al25Zn new aluminium material developed and found its mechanical properties. The Al25Zn has higher yield strength among its binary composition. The hardness is also higher. The addition of zinc to aluminium increases the hardness and yield strength. The new developed material properties used in stress and deformation analysis. The analysis results show that new material exhibit good properties for yield strength, stress which are less compared to steel material. This is because the stresses built are function of centrifugal forces which is mass dependent. New material has less mass compared to steel impeller as there is density variation. Identification of new material for impeller application is studied and it is observed that Standard Elastic Analysis (SEA) at initial stages helps in determining use of new material in impeller design. Key Words: Centrifugal Compressor, Impeller, Blade, Stress, Deformation, SEA, FEA, Aluminium Alloy material. 1. INTRODUCTION The Centrifugal impellers are widely used in various fields such as oil and gas compressors, refineries, fertilizer plants, aviation, environmental protection, CO2 injection, LNG compression, Gas pipelines and pharmacy industry. The impeller is the most essential rotating part of a radial-flow turbo compressor which imparts its kinetic energy to the fluid and increases its pressure energy. It is the heart of the compressor which is composed of hub, blades, and shrouds. Compressor performance and reliability are closely related on the impellers. The stresses developed in impeller during working of compressor are higher and construction wise also it is the most complex than for any other component on the rotating element. In view of the ever increasing importance of its performance, the geometrical design of an impeller is governed by the laws of aerodynamics, thermodynamics, and stress analysis. Generally in oil and gas application fully enclosed, Semi-open impellers are used in multistage centrifugal, single stage compressors where high efficiency and stability is required. High thermal as well as mechanical distortions are developed. Impeller stresses can be categorized by origin, type, and location. The three types of stresses which are developing during the working of impeller are steady state, thermally induced, and vibratory stresses. Due to rotation of the impeller Steady state stresses are centrifugally induced and these stresses are proportional to the square of the tip speed of the impeller. Small amount of stresses are also developed as a result of the operating gas forces. However we treat impeller as non-pressure retaining component unlike compressor case and these effects are not considered in SEA analysis. There are axial forces acting on Impeller as well. The quantum of these forces depends on stage differential pressure. These forces gets nullify over impeller eye due to same pressure on either side of impeller. Only differential pressure will act below Impeller eye area on disc side. This unbalance force is balanced with the help of balancing device on rotor. Other form of steady state stresses are induced due to the shrink fit. Shrink fit is necessary to maintain positive mounting of the impeller for torque transmissions capability. Sometimes the excessive interference may result in the high amount of compressive stresses at the impeller bore (Toe fit). Sometimes, the contact pressure may not be sufficient to hold it in that case area is increased or additional fit is provided. Thermal stresses can be developed during the manufacturing or during the operation because of the exposure of the impeller to varying temperature, excessive speed and feed. Perhaps the most sophisticated area of impeller stress analysis is the area of SEA. When operated away from the design conditions the centrifugal compressors Impellers may experience high amount of centrifugal stresses, which can cause a serious structural damage to impeller. 1.1. SEA ANALYSIS