Recycle gas compressor module level and design method thereof

The invention belongs to the centrifugal compressor module level, specifically to a recycle gas compressor module level and a design method thereof, suitable for the modeling design of the recycle gas compressor product for all of polyethylene and polypropylene units as well as the centrifugal compressor product for other units having similar parameters. The module level comprises a semi-open three-dimensional flow impeller and a vane diffuser; the modeling design of the centrifugal compressor performed according to the similar modeling theory can provide the module level for the similar modeling design of the recycle gas compressor for the polyethylene and polypropylene units of different sizes. The parameters of module level are as follows: the machine mach Mu2 is 0.5; the flow coefficient Phi1 is 0.152; the energy head coefficient T is 0.54; and the variable frequency Hpo1 is 0.82-0.84. The application of the large flow coefficient module level enables the recycle gas compressor for the polyethylene and po