elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Strategies for Multi-Fidelity Optimization of Multi-Stage Compressors with Throughflow and 3D CFD

Schnoes, Markus and Schmitz, Andreas and Goinis, Georgios and Voß, Christian and Nicke, Eberhard (2019) Strategies for Multi-Fidelity Optimization of Multi-Stage Compressors with Throughflow and 3D CFD. ISABE 2019, 23-27 Sep 2019, Canberra, Australia.

[img] PDF
997kB

Abstract

The aerodynamic design of turbomachinery is an exciting engineering problem that involves a vast design space and requires proficiency in multiple engineering disciplines. For multi-stage compressors, the large dimension of the design space arises from the geometric freedom to shape each blade row individually. Although the basis of most designs is formed by throughflow computations, the state-of-the art for aerodynamic evaluation is steady-state RANS. The computational expense for a single evaluation of a multi-stage machine with RANS is affordable, shape optimizations with hundreds of evaluations becomes expensive. This paper presents two strategies to tackle these problems: Firstly, a novel airfoil family is employed that helps to reduce the number of design parameters. It was generated based on a parametric study of optimal airfoil shape for varying design requirements. Secondly, an optimizer is used that supports simultaneous evaluations of the objective function on multiple fidelity levels. Here, cheap throughflow calculations are conducted on the low-fidelity side and RANS is used on the high-fidelity side. Inside the optimizer, multi-fidelity support is enabled by a Co-Kriging surrogate model. This approach is expected to speed-up the optimization by guiding expensive evaluations of the 3D CFD setup into promising regions of the design space. These strategies are assessed by testing different optimization setups for a four stage compressor. Both purely low and high-fidelity optimizations are conducted as well as multi-fidelity optimizations. In comparison to the baseline design, the isentropic efficiency predicted by RANS for the working line points on the 95% and the 100% speed line is increased by above 1.2%. The driving mechanism is a load redistribution between the stages that mainly reduces the shock strength of the second rotor.

Item URL in elib:https://elib.dlr.de/129457/
Document Type:Conference or Workshop Item (Speech)
Title:Strategies for Multi-Fidelity Optimization of Multi-Stage Compressors with Throughflow and 3D CFD
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Schnoes, Markusmarkus.schnoes (at) dlr.deUNSPECIFIED
Schmitz, AndreasAndreas.Schmitz (at) dlr.deUNSPECIFIED
Goinis, GeorgiosGeorgios.Goinis (at) dlr.deUNSPECIFIED
Voß, ChristianChristian.Voss (at) dlr.deUNSPECIFIED
Nicke, EberhardEberhard.Nicke (at) dlr.deUNSPECIFIED
Date:September 2019
Refereed publication:Yes
Open Access:Yes
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:Design Optimization, Throughflow, 3D CFD, Compressor, Co-Kriging, Multi-Fidelity
Event Title:ISABE 2019
Event Location:Canberra, Australia
Event Type:international Conference
Event Dates:23-27 Sep 2019
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Aeronautics
HGF - Program Themes:propulsion systems
DLR - Research area:Aeronautics
DLR - Program:L ER - Engine Research
DLR - Research theme (Project):L - Fan and Compressor Technologies
Location: Köln-Porz
Institutes and Institutions:Institute of Propulsion Technology > Fan and Compressor
Deposited By: Schnös, Markus
Deposited On:18 Nov 2019 12:12
Last Modified:18 Nov 2019 12:12

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.