Special programs for centrifugal compressor design have been developed at LUT in cooperation with HST to ensure optimal command of the design process.
1. The first phase is the definition of the main dimensions of the centrifugal compressor and the computation of a performance map with a one-dimensional, semi-empirical program.
2. After that shape of the impeller passages is optimized with a geometrical three-dimensional program.
3. The received vane geometry data file is then transferred to the numerical flow calculation (CFD) and strength calculation based on the element method, which are usually run parallel to save time.
The CFD calculation is done on a modified code of the Finnish FINFLO program (see Calculation of Flow Dynamics in a Radial Compressor and Turbine), and for the strength calculation HST uses a commercial code. Finally a data file of the essential parts of the compressor is produced for numerically controlled machining and casting.
4. After the prototype have been manufactured, the success of the design is verified with detailed measurements in the LUT measurement station.
Almost all the centrifugal compressors used by High Speed Tech LTD have been designed at LUT, and their performance characteristics have met the requirements well.
Two dissertations (Reunanen and Turunen-Saaresti) and one licentiate’s thesis has been done on the topic (Backman).