Abstract: A nitrogen circulating fan with the form of integral assembly centrifugal fan is needed for the acetic acid cogeneration plant from coal to hydrogen in a refined and chemical company. Its function is to supply gas to the process pipeline before the whole process operation and sweep the catalyst needed for the reaction into the reactor, and to complete the preparation work before the process. The equipment is a very critical part of the process flow, and its continuous and stable operation is crucial, so it has been using products of imported brands. The price of similar imported equipment for this device is very high and the manufacturing cycle is long, which cannot meet the site schedule requirements. Under this background, an integral assembled centrifugal compressor is developed to replace the imported one. The main research content covers: flow parts design and numerical simulation performance prediction; rotor dynamics calculation to improve the operation stability of the whole machine. After the design is completed, air medium test is used to verify the aerodynamic performance and mechanical operation results. The test results show that all the indexes meet the design requirements.

Key words: assembled centrifugal fan, numerical simulation, rotor dynamics calculation, air medium test