Research On Strength And Model Analysis Of Centrifugal Chillers

The body of the units is the main components in the centrifugal chillers, for it is used to support, fix and install other parts to maintaining every parts in their relatively constant position when the centrifugal chillers in operation. The strength and reliability of the body has importance significance to the normal work of the entire unit. To calculate the strength of the body and to analysis the safety and to improve the structure is important for further research. A failure of the body vibration usually occurs when the centrifugal water-cooled units in operation. The vibration of the units may lead to lowering the operating cycle, shrinking the life of units, increasing the ambient noise; what's more it can course the damaging of the unit components and trigger serious accidents. Therefore, in order to make the unit safe and stable operation, it is necessary to carry out vibration modal analysis.With the development of modern design, to analysis the strength of the structure and optimization has become the primary means of product updates through computer-aided tools, making it easier to improving the designing of the products. In the development of modern products, CAD/CAE/CAM integration method is widely used, the finite element method is the main method in CAE, which is a general numerical method for boundary value problem of ordinary equations. Application of finite element analysis have an important role in improving product quality, and shortening the design cycles and reducing the costs of product development, making products more competitive in the market.The thesis analyses the static strength and modal of the unit based on the basic theory of finite element.(1) The three-dimensional solid model of the body was established in the SolidWorks design software based on product design drawings, and model was simplified according to the actual necessaries. Introduce it into the SolidWorks simulation software for finite element analysis:setting the contact between the unit components, adding the load and constraints, joint processing, meshing and other treatments.(2) Do static strength analysis. Data of stress, strain and safety factor are achieved in specific working conditions through the analysis of strength. The stress changes of important parts and dangerous parts not only provide a basis for the improvement of the structural design but also provide finite element analysis method or reference for similar products.(3) Do structural model analysis. The resonant frequency of the top 20 bands and corresponding modal parameters are obtained and the distribution and changes of the vibration intensity is also get through modal analysis, the results provide theoretical reference for the design of the body.This thesis, which integrates the theoretical research and practical application, analyses centrifugal chiller based on finite element method. Test results show that the structure of the body can meet the actual engineering requirements.