A New Multistage Axial Compressor Designed With the Apnasa Multistage CFD Code: Part 1 — Code Calibration

The NASA Average-Passage multistage turbomachinery flow analysis code “APNASA” by J.J. Adamczyk (1985) has been validated, calibrated, and demonstrated at Honeywell Engines and Systems for the design of multistage axial compressors. APNASA was first calibrated against test data of two existing compressors and then used as a design tool in the design of a new modern multistage axial compressor. The results of the calibration, design effort, and the data measurements are presented in this two-part paper. In the present paper (Part 1) the results of the calibration for two multistage axial compressors are presented. The first compressor consists of four axial stages that were designed in the mid 1980s. The second compressor consists of three axial stages and was designed in the mid 1990s using viscous, three-dimensional CFD code, with airfoil optimization performed in single blade row fashion. The calibration work was aimed at developing meshing and modeling best practices and validating the code capability to simulate flow behavior in a multistage environment. Predictions are compared with test data for the axial compressor overall performance, individual stage performance, and detailed radial profiles at the stator vanes leading edge planes, throughout the compressor. Results show good agreement between APNASA predictions and measurement data. In particular, the results clearly demonstrate the ability of APNASA to capture the stage matching of multistage machines. As a result of this calibration/validation work, a new multistage axial compressor was subsequently designed, by using APNASA as the primary source of information for airfoil optimization (presented as Part 2 of this paper). Test results for the new compressor reveal that the design achieved its performance and operability goals in its first build. Details of the compressor design philosophy using APNASA and the comparison between APNASA simulation results and test data are presented in Part 2.