Internal Flow Analysis And Structure Optimization Design Of Single Stage Centrifugal Compressor

Centrifugal compressor is widely used in gas turbine and pressure increasing equipment on the condition of small flow rate because of a higher single stage compression ratio, the characteristics of light weight and simple manufacturing. Centrifugal compressor plays an important role in energy, metallurgy, aerospace and chemical industry, etc, so designing the centrifugal compressor with high efficiency, high pressure ratio and wide range of flow has the practical significance. This paper first used special centrifugal impeller designing software CFturbo to design a centrifugal impeller, which designing criteria is based on built-in functions in the software; then made a numerical simulation of the centrifugal impeller with a three-dimensional steady state by ANSYS CFX; at last optimized the the structure of the impeller and studied the matching of the diffuser on the basis of the above.In this paper, the main work is as follows:1. It is significant to understand the structure and function of the parts of centrifugal compressor ,summarize the research achievements of predecessors on the basis of the understanding of background ,introduce the experimental study and numerical study through related literature home and abroad.2. To test the reliability of numerical simulation, a performance experiment of centrifugal impeller compares with the results from CFD software is necessary.3. The centrifugal compressor is simulated in the rotate speed of 100%, 90%, 80%,70% , which the characteristic curve is based on. The analysis of the flow field of compressor is aimed at design condition, including generation mechanism, the development process and spatial location of the internal secondary flow. Based on the secondary flow, the wake-jet structure is studied mainly about generation mechanism and interaction with the secondary flow. In the last, wake-jet structure in different mass flow is focused on.4.The centrifugal compressor is optimized of impeller parameters which includes tip clearance, the leading edge shape of blade, the leading edge angle above and below of the blade.5.Firstly, the diffuser is designed by CFturbo, which the built-in functions and design principles is in the software. The study of diffuser is mainly about inlet and outlet angle which has relationship with the matching performance, in addition, the ratio of the diameter of diffuser inlet and impeller outlet, the consistency of the diffuser are also under consideration.