Download - High Speed Compressor Design
High Speed Compressor Design
Lucilene Moraes da Silva
Post Doctoral Researcher
Department of Mechanics and Maritime Sciences
Division of Fluid Dynamics
Workshop, Marine Technology and Fluid Dynamics
March 16, 2020
March 16, 2020 2
• Motivation
• Design features: conceptual / preliminary design and analysis
• Design challenges that are encountered when developing a high-speed axial
compressor
• Design Framework
• Work in-progress
Topics covered
Department of Mechanics and Maritime Sciences
3
Typical application Type of flow Pressure ratio per stage Efficiency per stage
Industrial Subsonic 1.05 - 1.2 88 - 92%
Aerospace Transonic 1.15 – 2.0 84 - 88%
EJ200 EngineEurofighter Typhoon Transonic Compressor
Motivation
March 16, 2020 Department of Mechanics and Maritime Sciences
4March 16, 2020 Department of Mechanics and Maritime Sciences
Motivation
Requirements of next-generation fighter
aircraft:
• Maximum range and high mission
flexibility.
• Long operating times, and
predictable life-cycle costs that are
as low as possible, plus a low radar
signature.
https://www.mtu.de/the-new-european-fighter-jet/
Improvements of high speed compressor
design:
• It allows higher pressure ratios per single-
stage, resulting in reduction of the engine
weight and size and, therefore, investment
and operational costs.
• Small increment in efficiency, can result in
huge savings in fuel costs, improvement of
rotor stability towards near stall conditions,
resulting in a wider working range.
5
Design Features
March 16, 2020 Department of Mechanics and Maritime Sciences
Lejon, C. Et al. Multidisciplinary Design of a Three Stage High
Speed Booster. GT2017-64466
6March 16, 2020 Department of Mechanics and Maritime Sciences
In order to maintain good flow over the blade
certain conditions must be meet.
• The relative flow angle and the inlet blade angle
must be close to prevent flow separation from the
blade.
• The turning angle (deflection) must be keep quite
small, or the flow will also separate from the blade.
• The relative flow velocity must not be too close to
the speed of sound. This is to prevent shock waves
from forming on the blade.
Design Challenges
7
shock waves
Intense secondary flows
Shock/boundary layer interaction
Development of blockage
Stall /flow separation
Flow interaction at rotor tip clearance
Reduction of Compressor Performance
Design Challenges
March 16, 2020 Department of Mechanics and Maritime Sciences
Entropy Generation
(Losses)
Saito, S. et al. Mechanisms and quantitative evaluation of flow loss
generation in a multi-stage transonic axial compressor. GT2019-90439
Department of Mechanics and Maritime Sciences 8March 16, 2020
Design Challenges
• Developing an efficient high speed axial compressor multistage design
• Loss models to predict the profile, secondary, transient and leakages losses.
• Accurately prediction of shock waves, experimental and numerical.
• Prediction of the surge limit.
Hergt, A. et al. The Present Challenge of Transonic Compressor Blade Design. Journal of Turbomachinery. September 2019, Vol. 141
Sketch of the numerical aerodynamic design point, numerical stall onset and comparison of the numerical and experimental stall
margin, respectively.
9
Design Framework
March 16, 2020 Department of Mechanics and Maritime Sciences
Preliminary Design Blade Generation
11
Work in-progress
• Working with re-design an stage of axial compressor using the design
framework aiming to improve the stage efficiency through rotor blade
optimization.
• Working with a conference article about optimal aspect ratio for high speed
compressor.
• Working how to assessment and breakdown of losses in high speed
compressor.
March 16, 2020 Department of Mechanics and Maritime Sciences