A 3D-Navier-Stokes solver was used to analyse the complete flow field of the 15-stage axial compressor of Siemens model V84.3A advanced gas turbine. The paper presents the flow simulation including modelling of rotor tip clearances and bleeds for turbine cooling air supply. All computations were performed for coupled blade rows to account for the time averaged impact of interaction effects arising from adjacent airfoil rows. The evaluation of such two-blade-row calculations allows the update of the inlet boundary conditions for the following downstream two-blade-row combination. Successive computations from inlet guide vanes to exit stator thus yield the flow field of the whole compressor. The main objective is the analysis of the numerical results. Special attention is given to the front stage, stage matching, endwall flow effects, tip leakage and the cooling air extractions. The comparison to experimental data of the full load gas turbine test facility generally shows a good agreement. The results demonstrate the reliability and power of a modern CFD tool to perform advanced design studies, geometry modifications and calibration of fast 2D-Codes more efficiently and less expensively than performing any physical experiments.
In consideration of further jet-engine developments required by applications for supersonic travel aircraft, airbreathing propulsion of space vehicles, or only the improvement of conventional high-performance turbo-engines, highly loaded supersonic compressors seem to meet the future demands. Particularly mixed-flow compressor stages with moderate supersonic rotor and stator inlet flow reveal the potential of high pressure rise and mass flow as well as favorable performance characteristics and efficiency. The first part of this paper presents analytical considerations for mixed-flow supersonic compressors with strong shock waves. This theoretical approach proves to be essential besides established design tools in order to ensure safe rotor and stage operation in accordance with the design objectives. In this context, the conditions for shock wave stabilization within a diagonal rotor passage are discussed in detail for design and off-design rotational speeds. The main part of this paper, however, presents the results and flow analysis obtained by extensive experimental investigations of the designed mixed-flow compressor rotor. The investigations were restricted to operation without stator in order to strictly separate rotor performance from rotor-stator interactions. The results reveal the design goals to be met in general. Mass flow, total pressure rise, and efficiency in particular show a good agreement with the design properties for near-surge operation at design and off-design conditions.
Highly loaded transonic and supersonic compressors appear capable of meeting the future demands of small gas turbines and jet engines. Particularly mixed flow compressors, taking advantage of the increasing circumferential blade speed between rotor inlet and exit, represent a good compromise with regard to high pressure ratio and mass flow on the one hand, and favorable performance characteristics and efficiency on the other. However, operating a supersonic rotor as part of a stage involves a stator characterized by high turning angles, supersonic inlet conditions and a strong flow deceleration. In fact, the stator can be identified as the critical component regarding overall stage performance. Based on experimentally determined rotor exit flow conditions, the first part of this paper describes the design of a tandem stator with a strong shock in the stator entrance region, followed by subsonic flow turning and diffusion. The main thrust of this paper is to present the analytical results obtained in connection with the experimental investigation of the complete stage at design and off-design conditions. Rotor and stator flow as well as the overall stage performance are discussed in detail. The concept of the tandem stator proves to be suitable for managing the extremely high aerodynamic loading in the Stator. Experimental results reveal the design goals to be met in general.
In consideration of further jet-engine developments required by applications for supersonic travel aircraft, airbreathing propulsion of space vehicles or only the improvement of conventional high performance turbo engines, highly loaded supersonic compressors seem to meet the future demands. Particularly mixed-flow compressor stages with moderate supersonic rotor- and stator inlet flow reveal the potential of high pressure rise and massflow as well as favorable performance characteristics and efficiency. The first part of this paper presents analytical considerations for mixed-flow supersonic compressors with strong shock waves. This theoretical approach proves to be of essential importance besides established design tools in order to ensure safe rotor and stage operation in accordance with the design objectives. In this context, the conditions for shock wave stabilization within a diagonal rotor passage are discussed in detail for design and off-design rotational speeds. The main part of this paper, however, presents the results and flow analysis obtained by extensive experimental investigations of the designed mixed-flow compressor rotor. The investigations were restricted to operation without stator in order to strictly separate rotor performance from rotor-stator interactions. The results reveal the design goals to be met in general. Massflow, total pressure rise and efficiency in particular show a good agreement with the design properties for near-surge operation at design and off-design conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.