CENTRFUGAL COMPRESSOR ANALYSIS
Traditionally, for centrifugal compressor operation
analysis for design and off-design points, the verification
analysis problem has been performed in 1D
In verification analysis of a centrifugal compressor,
flow is treated as one-dimensional only . Obviously,
there is significant 3D flow in a centrifugal compressor.
Considering the importance of quick review of design
results, a 3D potential flow solver was developed and
embedded into the system.
In contrast to 3D viscous flow calculations in a flow
path, simplified 1D methods provide a close
approximation for experimental data depending on the
quality of empirical methods used to determine losses
and deviation angles.
Due to the absence of reliable energy loss and flow
deviation angles in cascades, there is a significant
challenge in developing radial turbomachinery
verification calculation algorithms. In practice,  the
various known construction losses obtained from
experimental data are used.
Centrifugal compressor flow path losses and outlet
flow deviation angles are estimated based on existing
data in literature [5,6]. Though obtained results can be
characterized as satisfactory, loss models require further
refinement One way of increasing the reliability of
results is the use of custom libraries for proven loss
models within the integrated design system environment.
The typical approach to solve this task and boundary
condition is presented in . The authors of this paper
used the same method, so it is not necessary to explain it.
As an example, validation of the 1D solver was
performed based on experimental data presented in .
Flow path of the compressor shown in Fig.2 was
studied with both a vaned and a vaneless diffuser.
Performance calculations show a close correlation of the
obtained efficiency with experimental data for the
vaneless diffuser design in a quantitative sense and a
close correlation for vaned diffuser design in a
qualitative sense (Fig.3). Efficiency levels at 80%
rotation speed coincide closely with experimental data as
well. (Fig.4, Fig.6). The literature only cites CFD
calculations results (Figs.7a,7b,7c,7d) and experimental
data at an 80% rotation speed (,  etc.). These
results correlate closely to experimental data at an 80%
speed as well.