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Journal articles on the topic 'Design of axial compressors'
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1
Gallimore, S. J. "Axial flow compressor design†." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 213, no. 5 (May 1, 1999): 437–49. http://dx.doi.org/10.1243/0954406991522680.
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The purpose of this paper is to set out some of the basic principles and rules associated with the design of axial flow compressors, principally for aero-engines, as well as the practical constraints that are inevitably present. The thrust is primarily on the aerodynamic design but this cannot be divorced from the mechanical aspects and so some of these are touched upon but are not gone into so deeply. The paper has been written from the point of view of the designer and tries to cover most of the points that need to be considered in order to produce a successful compressor. The emphasis has been on the theory behind the design process and on minimizing the reliance on empirical rules. However, because of the complexity of the flow, some empiricism still remains.
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Hönen, H. "Axial Compressor Stall and Surge Prediction by Measurements." International Journal of Rotating Machinery 5, no. 2 (1999): 77–87. http://dx.doi.org/10.1155/s1023621x9900007x.
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The paper deals with experimental investigations and analyses of unsteady pressure distributions in different axial compressors. Based on measurements in a single stage research compressor the influence of increasing aerodynamic load onto the pressure and velocity fluctuations is demonstrated. Detailed measurements in a 14-stage and a 17-stage gas turbine compressor are reported. For both compressors parameters could be found which are clearly influenced by the aerodynamic load.For the 14-stage compressor the principles for the monitoring of aerodynamic load and stall are reported. Results derived from a monitoring system for multi stage compressors based on these principles are demonstrated. For the 17-stage compressor the data enhancement of the measuring signals is shown. The parameters derived from these results provide a good base for the development of another prediction method for the compressor stability limit. In order design an on-line system the classification of the operating and load conditions is provided by a neural net. The training results of the net show a good agreement with different experiments.
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Leichtfuß, Sebastian, Johannes Bühler, Heinz-Peter Schiffer, Patrick Peters, and Michael Hanna. "A Casing Treatment with Axial Grooves for Centrifugal Compressors." International Journal of Turbomachinery, Propulsion and Power 4, no. 3 (August 16, 2019): 27. http://dx.doi.org/10.3390/ijtpp4030027.
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This paper provides an investigation of a casing treatment (CT) approach for pressure ratio improvements of centrifugal compressors between peak efficiency and surge. Results were experimentally verified for a variety of automotive turbocharger compressors and analyzed with 3D CFD. The CT design is an adaptation from an axial high-pressure compressor, which was successfully applied and intensively investigated in recent years. The aerodynamic working principle of the applied CT design and the achievable improvements are shown and described. The demand of operating range for automotive applications typically dictates high inlet shroud to outlet radius ratio (high trim) and past experiences indicate that a recirculation zone is formed in the inducer for those centrifugal compressors. This recirculation at the inlet shroud causes losses, a massive blockage and induces a co-rotating swirl at the inlet of the impeller. The result is a reduced pressure ratio, often leading to flat speed lines between the onset of recirculation and surge. This paper provides an understanding of inducer recirculation, its impacts and suggests countermeasures. The CT design for centrifugal compressors only influences flow locally at the inducer and prevents recirculation. It differs substantially in design and functionality from the classical bleed slot system commonly used to increase operating range. An experimental and CFD comparison between these designs is presented. While the classical bleed slot system often provides a massive increase in operating range, it often fails to increase the pressure ratio between onset of inducer recirculation and surge. In contrast, the CT design achieves a gain in pressure ratio near surge.
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Kalinkevych, M., V. Ihnatenko, O. Bolotnikova, and O. Obukhov. "Design of high efficiency centrifugal compressors stages." Refrigeration Engineering and Technology 54, no. 5 (October 31, 2018): 4–9. http://dx.doi.org/10.15673/ret.v54i5.1239.
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The modern trend in compressor industry is an extension of the use of multi-shaft centrifugal compressors. Multi-shaft compressors have a number of advantages over single-shaft. The design of such compressors gives opportunity to use an axial inlet for all stages and select the optimum rotational speed for each pair of impellers, which, along with the cooling of the gas after each stage, makes possible to achieve high levels of efficiency. The design of high-efficiency centrifugal compressor stages can be performed on the basis of highly effective stage elements. Such elements are: impellers with spatial blades, vaned and channel diffusers with given velocity distribution. In this paper, impellers with axial-radial blades are considered. The blade profile is determined by the specified pressure distribution along the blade. Such design improves the structure of the gas flow in the interblade channels of the impeller, which leads to an increase in its efficiency. Characteristics of loss coefficients from attack angles for impellers were obtained experimentally. Vaned and channel diffusers, the characteristics of which are given in this article, are designed with the given velocity distribution along the vane. Compared to the classic type of diffuser, such diffusers have lower losses and a wider range of economical operation. For diffusers as well as for impellers, characteristics of loss coefficients from attack angles were obtained. High efficient impellers and diffusers and obtained gas-dynamic characteristics were used in the design of a multi-shaft compressor unit for the production of liquefied natural gas. The initial pressure of the unit is 3bar. The obtained characteristics of loss coefficients from attack angles for the considered impellers and diffusers make it possible to calculate the gas-dynamic characteristics of high-efficient centrifugal compressors stages. The high-efficient centrifugal compressors stages can be designed using high-efficient elements, such as: impeller with spatial blades and vaned diffuser with given velocity distribution.
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Sehra, A., J. Bettner, and A. Cohn. "Design of a High-Performance Axial Compressor for Utility Gas Turbine." Journal of Turbomachinery 114, no. 2 (April 1, 1992): 277–86. http://dx.doi.org/10.1115/1.2929141.
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An aerodynamic design study to configure a high-efficiency industrial-size gas turbine compressor is presented. This study was conducted using an advanced aircraft engine compressor design system. Starting with an initial configuration based on conventional design practice, compressor design parameters were progressively optimized. To improve the efficiency potential of this design further, several advanced design concepts (such as stator ends bends and velocity controlled airfoils) were introduced. The projected poly tropic efficiency of the final advanced concept compressor design having 19 axial stages was estimated at 92.8 percent, which is 2 to 3 percent higher than the current high-efficiency aircraft turbine engine compressors. The influence of variable geometry on the flow and efficiency (at design speed) was also investigated. Operation at 77 percent design flow with inlet guide vanes and front five variable stators is predicted to increase the compressor efficiency by 6 points as compared to conventional designs having only the inlet guide vane as variable geometry.
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Jianguo, Q. "Modification for scroll wrap height of a scroll compressor." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 3 (September 14, 2011): 763–74. http://dx.doi.org/10.1177/0954406211414640.
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In order to obtain better axial hermetic seal of scroll compression chambers and hence a better performance for a scroll compressor, two modification methods for scroll wrap height are proposed based on the axial deformation of the scroll wrap. First, the design modification, which allows the scroll wrap height and its dimensional tolerances to be designed based on the axial deformation of scroll wrap in the basic shaft system, is suitable for mass production of scroll compressors. Second, the special modification, which allows the scroll wrap height to be modified based on the axial deformation of scroll wrap after its manufacturing, can be used for single-piece production of scroll compressor or for the scroll compressors available. A special modification was conducted for a scroll compressor, in which the orbiting scroll wrap was modified based on the simulation results of its axial deformation. According to the tests conducted later, the performance of the scroll compressor with modified scroll wrap can significantly be improved without deteriorating its original manufacturing precision.
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Khalid, S. A., A. S. Khalsa, I. A. Waitz, C. S. Tan, E. M. Greitzer, N. A. Cumpsty, J. J. Adamczyk, and F. E. Marble. "Endwall Blockage in Axial Compressors." Journal of Turbomachinery 121, no. 3 (July 1, 1999): 499–509. http://dx.doi.org/10.1115/1.2841344.
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This paper presents a new methodology for quantifying compressor endwall blockage and an approach, using this quantification, for defining the links between design parameters, flow conditions, and the growth of blockage due to tip clearance flow. Numerical simulations, measurements in a low-speed compressor, and measurements in a wind tunnel designed to simulate a compressor clearance flow are used to assess the approach. The analysis thus developed allows predictions of endwall blockage associated with variations in tip clearance, blade stagger angle, inlet boundary layer thickness, loading level, loading profile, solidity, and clearance jet total pressure. The estimates provided by this simplified method capture the trends in blockage with changes in design parameters to within 10 percent. More importantly, however, the method provides physical insight into, and thus guidance for control of, the flow features and phenomena responsible for compressor endwall blockage generation.
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Camp, T. R., and J. H. Horlock. "An Analytical Model of Axial Compressor Off-Design Performance." Journal of Turbomachinery 116, no. 3 (July 1, 1994): 425–34. http://dx.doi.org/10.1115/1.2929429.
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An analysis is presented of the off-design performance of multistage axial-flow compressors. It is based on an analytical solution, valid for small perturbations in operating conditions from the design point, and provides an insight into the effects of choices made during the compressor design process on performance and off-design stage matching. It is shown that the mean design value of stage loading coefficient (ψ = Δh0/U2) has a dominant effect on off-design performance, whereas the stage-wise distribution of stage loading coefficient and the design value of flow coefficient have little influence. The powerful effects of variable stator vanes on stage-matching are also demonstrated and these results are shown to agree well with previous work. The slope of the working line of a gas turbine engine, overlaid on overall compressor characteristics, is shown to have a strong effect on the off-design stage-matching through the compressor. The model is also used to analyze design changes to the compressor geometry and to show how errors in estimates of annulus blockage, decided during the design process, have less effect on compressor performance than has previously been thought.
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Wennerstrom, A. J. "Low Aspect Ratio Axial Flow Compressors: Why and What It Means." Journal of Turbomachinery 111, no. 4 (October 1, 1989): 357–65. http://dx.doi.org/10.1115/1.3262280.
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One of the more visible changes that has occurred in fans and compressors for aircraft turbine engines that have entered development since about 1970 has been a significant reduction in the aspect ratio of the blading. This has brought with it a greatly reduced engine parts count and improved ruggedness and aeroelastic stability. This paper traces the evolution of thinking concerning appropriate aspect ratios for axial flow compressors since the early years of the aircraft turbine engine. In the 1950’s, moderate aspect ratios were favored for reasons of mechanical design. As mechanical design capability became more sophisticated, several attempts were made, primarily in the 1960s, to employ very high aspect ratios to reduce engine size and weight. Four of these programs are described that were largely unsuccessful for both mechanical and aerodynamic reasons. After 1970, the pendulum swung strongly in the other direction and designs of very low aspect ratio began to emerge. This has had a significant impact on compressor design systems, and a number of the ways in which design systems have been affected are discussed. Some concluding remarks are made concerning the author’s opinion of trends in the near future in aerodynamic design technology.
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Sieverding, Frank, Beat Ribi, Michael Casey, and Michael Meyer. "Design of Industrial Axial Compressor Blade Sections for Optimal Range and Performance." Journal of Turbomachinery 126, no. 2 (April 1, 2004): 323–31. http://dx.doi.org/10.1115/1.1737782.
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Background: The blade sections of industrial axial flow compressors require a wider range from surge to choke than typical gas turbine compressors in order to meet the high volume flow range requirements of the plant in which they operate. While in the past conventional blade profiles (NACA65 or C4 profiles) at moderate Mach number have mostly been used, recent well-documented experience in axial compressor design for gas turbines suggests that peak efficiency improvements and considerable enlargement of volume flow range can be achieved by the use of so-called prescribed velocity distribution (PVD) or controlled diffusion (CD) airfoils. Method of approach: The method combines a parametric geometry definition method, a powerful blade-to-blade flow solver and an optimization technique (breeder genetic algorithm) with an appropriate fitness function. Particular effort has been devoted to the design of the fitness function for this application which includes non-dimensional terms related to the required performance at design and off-design operating points. It has been found that essential aspects of the design (such as the required flow turning, or mechanical constraints) should not be part of the fitness function, but need to be treated as so-called “killer” criteria in the genetic algorithm. Finally, it has been found worthwhile to examine the effect of the weighting factors of the fitness function to identify how these affect the performance of the sections. Results: The system has been tested on the design of a repeating stage for the middle stages of an industrial axial compressor. The resulting profiles show an increased operating range compared to an earlier design using NACA65 profiles. Conclusions: A design system for the blade sections of industrial axial compressors has been developed. Three-dimensional CFD simulations and experimental measurements demonstrate the effectiveness of the new profiles with respect to the operating range.
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Gallimore, Simon J., John J. Bolger, Nicholas A. Cumpsty, Mark J. Taylor, Peter I. Wright, and James M. M. Place. "The Use of Sweep and Dihedral in Multistage Axial Flow Compressor Blading—Part I: University Research and Methods Development." Journal of Turbomachinery 124, no. 4 (October 1, 2002): 521–32. http://dx.doi.org/10.1115/1.1507333.
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This paper describes the introduction of 3-D blade designs into the core compressors for the Rolls-Royce Trent engine with particular emphasis on the use of sweep and dihedral in the rotor designs. It follows the development of the basic ideas in a university research project, through multistage low-speed model testing, to the application to high pressure engine compressors. An essential element of the project was the use of multistage CFD and some of the development of the method to allow the designs to take place is also discussed. The first part of the paper concentrates on the university-based research and the methods development. The second part describes additional low-speed multistage design and testing and the high-speed engine compressor design and test.
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Musgrave, D. S., and N. J. Plehn. "Mixed-Flow Compressor Stage Design and Test Results With a Pressure Ratio of 3:1." Journal of Turbomachinery 109, no. 4 (October 1, 1987): 513–19. http://dx.doi.org/10.1115/1.3262141.
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This paper presents a brief history of mixed-flow compressors, possible applications, and the design and measured performance of a recently tested 3:1 pressure-ratio stage. The stage is intended to run behind a multistage axial compressor; it has an envelope radius only 9.4 percent greater than the rotor tip radius. A tandem cascade diffusing system is used to promote flow range and thus aid matching to the axial stages. Compressor maps from the rig test are presented along with additional data (from static taps and exit rakes) that characterize the behavior of various elements of the stage.
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Calvert, W. J., and R. B. Ginder. "Transonic fan and compressor design." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 213, no. 5 (May 1, 1999): 419–36. http://dx.doi.org/10.1243/0954406991522671.
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Transonic fans and compressors are now widely used in gas turbine engines because of their benefits in terms of compactness and reduced weight and cost. However, careful and precise design is essential if high levels of performance are to be achieved. In this paper, the evolution of transonic compressor designs and methods is outlined, followed by more detailed descriptions of current compressor configurations and requirements and modern aerodynamic design methods and philosophies. Current procedures employ a range of methods to allow the designer to refine a new design progressively. Overall parameters, such as specific flow and mean stage loading, the axial matching between the stages at key operating conditions and the radial matching between the blade rows are set in turn, using one- and two-dimensional techniques. Finally, detailed quasi-three-dimensional and three-dimensional computational fluid dynamics (CFD) analyses are employed to refine the design. However, it is important to appreciate that the methods all have significant limitations and designers must take this into account if successful compressors are to be produced.
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Storace, A. F., D. C. Wisler, H. W. Shin, B. F. Beacher, F. F. Ehrich, Z. S. Spakovszky, M. Martinez-Sanchez, and S. J. Song. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part I—Experiment." Journal of Turbomachinery 123, no. 3 (February 1, 2000): 433–45. http://dx.doi.org/10.1115/1.1378299.
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An experimental and theoretical investigation has been conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor is displaced from the centerline of the static structure of the engine. This creates circumferentially nonuniform rotor-tip clearances, unsteady flow, and potentially increased clearances if the rotating and stationary parts come in contact. The result not only adversely affects compressor stall margin, pressure rise capability, and efficiency, but also generates an unsteady, destabilizing, aerodynamic force, called the Thomas/Alford force, which contributes significantly to rotor whirl instabilities in turbomachinery. Determining both the direction and magnitude of this force in compressors, relative to those in turbines, is especially important for the design of mechanically stable turbomachinery components. Part I of this two-part paper addresses these issues experimentally and Part II presents analyses from relevant computational models. Our results clearly show that the Thomas/Alford force can promote significant backward rotor whirl over much of the operating range of modern compressors, although some regions of zero and forward whirl were found near the design point. This is the first time that definitive measurements, coupled with compelling analyses, have been reported in the literature to resolve the long-standing disparity in findings concerning the direction and magnitude of whirl-inducing forces important in the design of modern axial-flow compressors.
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McGee, O. G., M. B. Graf, and L. G. Fre´chette. "Tailored Structural Design and Aeromechanical Control of Axial Compressor Stall—Part I: Development of Models and Metrics." Journal of Turbomachinery 126, no. 1 (January 1, 2004): 52–62. http://dx.doi.org/10.1115/1.1644555.
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This two-part paper presents general methodologies for the evaluation of passive compressor stabilization strategies using tailored structural design and aeromechanical feedback control (Part I), and quantitatively compares the performance of several aeromechanical stabilization approaches which could potentially be implemented in gas turbine compression systems (Part II). Together, these papers offer a systematic study of the influence of ten aeromechanical feedback controllers to increase the range of stable compressor operation, using static pressure sensing and local structural actuation to postpone modal stall inception. In this part, the stability of aeromechanically compensated compressors was determined from the linearized structural-hydrodynamic equations of stall inception. New metrics were derived, which measure the level of aeromechanical damping, or control authority of aeromechanical feedback stabilization. They indicate that the phase between the pressure disturbances and the actuation is central to assess the impact of aeromechanical interactions on compressors stability.
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SINGH, Prabhat, and Dharmahinder Singh CHAND. "VIGV Angle Optimization for Subsonic Axial Flow Compressor." INCAS BULLETIN 12, no. 2 (June 5, 2020): 217–28. http://dx.doi.org/10.13111/2066-8201.2020.12.2.18.
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Long-term performance of an axial-flow compressor by the scheduling of inlet guide vanes at off-design conditions has been studied in this paper. The compressors are used in various industries and in aviation sectors for different operations at different climatic conditions; due to diverse climatic conditions the compressor is unable to give good performances as expected. At the design conditions, the results show that the variations in total pressure loss coefficient, volume flow rate, pressure ratio, and others like thermodynamics, aerodynamic properties are different at different stagger angles of 15°, 30° and 45°. BladeGen tools were used to design the inlet guide vanes for the investigations. The performance parameters of the axial flow compressor were analyzed by using ANSYS CFX and were validated using the analytical method. The objective of this study is to minimize the total pressure loss coefficient and improve the aerodynamic characteristics of an inlet guide vanes at different stagger angles and hence reduce the overall fuel consumption. The outcomes of this work give an improved insight into the efficient use of a VIGV in axial flow compressor.
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Cruz-Manzo, Samuel, Senthil Krishnababu, Vili Panov, and Chris Bingham. "Inter-Stage Dynamic Performance of an Axial Compressor of a Twin-Shaft Industrial Gas Turbine." Machines 8, no. 4 (December 9, 2020): 83. http://dx.doi.org/10.3390/machines8040083.
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In this study, the inter-stage dynamic performance of a multistage axial compressor is simulated through a semi-empirical model constructed in the Matlab Simulink environment. A semi-empirical 1-D compressor model developed in a previous study has been integrated with a 0-D twin-shaft gas turbine model developed in the Simulink environment. Inter-stage performance data generated through a high-fidelity design tool and based on throughflow analysis are considered for the development of the inter-stage modeling framework. Inter-stage performance data comprise pressure ratio at various speeds with nominal variable stator guide vane (VGV) positions and with hypothetical offsets to them with respect to the gas generator speed (GGS). Compressor discharge pressure, fuel flow demand, GGS and power turbine speed measured during the operation of a twin-shaft industrial gas turbine are considered for the dynamic model validation. The dynamic performance of the axial-compressor, simulated by the developed modeling framework, is represented on the overall compressor map and individual stage characteristic maps. The effect of extracting air through the bleed port in the engine center-casing on transient performance represented on overall compressor map and stage performance maps is also presented. In addition, the dynamic performance of the axial-compressor with an offset in VGV position is represented on the overall compressor map and individual stage characteristic maps. The study couples the fundamental principles of axial compressors and a semi-empirical modeling architecture in a complementary manner. The developed modeling framework can provide a deeper understanding of the factors that affect the dynamic performance of axial compressors.
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Law, C. H., and A. J. Wennerstrom. "Performance of Two Transonic Axial Compressor Rotors Incorporating Inlet Counterswirl." Journal of Turbomachinery 109, no. 1 (January 1, 1987): 142–48. http://dx.doi.org/10.1115/1.3262059.
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A single-stage axial-flow compressor which incorporates rotor inlet counterswirl to improve stage performance is discussed. Results for two rotor configurations are presented, including design and experimental test data. In this compressor design, inlet guide vanes were used to add counterswirl to the inlet of the rotor. The magnitude of the counterswirl was radially distributed to maximize the overall stage efficiency by minimizing the rotor combined losses (diffusion losses and shock losses). The shock losses were minimized by simultaneously optimizing the rotor blade section geometry, through-blade static pressure distribution, and leading edge aerodynamic/geometric shock sweep angles. Results from both the design and experimental performance analyses are presented and comparisons are made between the experimental data and the analyses and between the performance of both rotor designs. The computation of the flow field for both rotor designs and for the analysis of both tests was performed in an identical fashion using an axisymmetric, streamline-curvature-type code. Results presented include tip section blade-to-blade static pressure distributions and rotor through-blade and exit distributions of various aerodynamic parameters. The performance of this compressor stage represents a significant improvement in axial compressor performance compared to previous attempts to use rotor inlet counterswirl and to current, more conventional, state-of-the-art axial compressors operating under similar conditions.
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Niehuis, R., A. Bohne, and A. Hoynacki. "Experimental investigation of unsteady flow phenomena in a three-stage axial compressor." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 217, no. 4 (January 1, 2003): 341–48. http://dx.doi.org/10.1243/095765003322315397.
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In the past years, a three-stage axial compressor equipped with a modern controlled diffusion airfoil (CDA) blading has been investigated in much detail, applying state-of-the-art steady and unsteady measurement techniques, at RWTH Aachen University. The compressor under investigation exhibits design features of real industrial compressors. By performing high-resolution measurements both in space and time, a thorough insight into various flow phenomena in the compressor has been achieved, leading to a better understanding of various flow phenomena such as rotor—stator interaction, tip clearance flow and viscous flow effects in a multistage compressor environment. After a short summary of some performance characteristics at design and off-design, this paper focuses on the analysis of interaction phenomena present in the three-stage axial compressor. The interaction phenomena are described on a more global scale. In order to quantify the upstream and downstream influence of the three rotor blades, a suitable parameter is presented.
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Wu, Xiaoxiong, Bo Liu, Nathan Ricks, and Ghader Ghorbaniasl. "Surrogate Models for Performance Prediction of Axial Compressors Using through-Flow Approach." Energies 13, no. 1 (December 30, 2019): 169. http://dx.doi.org/10.3390/en13010169.
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Two-dimensional design and analysis issues on the meridional surface, which is important in the preliminary design procedure of compressors, are highly dependent on the accuracy of empirical models, such as the prediction of total pressure loss model and turning flow angle. Most of the widely used models are derived or improved from experimental data of some specific cascades with low-loading and low-speed airfoil types. These models may work for most conventional compressors but are incapable of accurately estimating the performance for some specific cases like transonic compressors. The errors made by these models may mislead the final design results. Therefore, surrogate models are developed in this work to reduce the errors and replace the conventional empirical models in the through-flow calculation procedure. A group of experimental data considering a two-stage transonic compressor is used to generate the airfoils database for training the surrogate models. Sensitivity analysis is applied to select the most influential features. Two supervised learning approaches including support vector regression (SVR) and Gaussian process regression (GPR) are used to train the models with a Bayesian optimization algorithm to obtain the optimal hyper parameters. The trained models are integrated into the through-flow code based on streamline curvature method (SLC) to predict the overall performance and internal flow field of the transonic compressor on five rotational speed lines for validation. The predictions are compared with the experimental data and the results of conventional empirical models. The comparison shows that SVR and GPR respectively reduce the predicted error of empirical models by 62.2% and 55.2% for the total pressure ratio and 48.4% and 50.1% for adiabatic efficiency on average. This suggests that the surrogate models constitute an alternative way to predict the performance of airfoils in through-flow calculation where empirical models are inefficient.
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Kipouros, Timoleon, Daniel M. Jaeggi, William N. Dawes, Geoffrey T. Parks, A. Mark Savill, and P. John Clarkson. "Biobjective Design Optimization for Axial Compressors Using Tabu Search." AIAA Journal 46, no. 3 (March 2008): 701–11. http://dx.doi.org/10.2514/1.32794.
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Savchenko, Vladislav, Vitalii Blinov, and Sergei Shamanin. "DEVELOPMENT OF AN EXPERIMENTAL AXIAL STAND COMPRESSORS USING ADDITIVE TECHNOLOGIES." Perm National Research Polytechnic University Aerospace Engineering Bulletin, no. 64 (2021): 33–42. http://dx.doi.org/10.15593/2224-9982/2021.64.04.
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In practice, the creation of compressor units is impossible without a large amount of experimental work. A lot of money is being invested in solving this problem, and many people participate in testing. Almost all calculation methods that are used in design are experimental and theoretical. In this regard, the modernization of calculation methods is inextricably linked with the development of experimental research, improvement of means and methods of measurements. In this paper, the created miniature experimental stand of a two-stage axial compressor is described, the general scheme of the stand is shown, the systems are described in detail. Several experiments were carried out at different speeds of rotation with different loads, the results were analyzed. Methods for obtaining characteristics of axial compressors using a software package for numerical three-dimensional thermodynamics modeling are presented. The described compressor unit has a set of sensors for collecting flow parameters in different planes. The signals from the sensors are processed by an eight-bit microcontroller. The stand is made of plastic using fused deposition modeling (FDM) on a 3D printer. Preliminary calculations of the strength of the rotor structure elements were carried out, the materials recommended for the manufacture of the installation were determined. The stand is proposed to be used for the design and optimization of two-stage compressor, as well as in the educational process. Also, in this article describes a constructed numerical model for studying the flow parameters of a compressor, presents the results of comparing some experimental and calculated data, constructs a flow characteristic, estimates the measurement uncertainty, and formulates several recommendations.
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Wisler, D. C. "Loss Reduction in Axial-Flow Compressors Through Low-Speed Model Testing." Journal of Engineering for Gas Turbines and Power 107, no. 2 (April 1, 1985): 354–63. http://dx.doi.org/10.1115/1.3239730.
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A systematic procedure for reducing losses in axial-flow compressors is presented. In this procedure, a large, low-speed, aerodynamic model of a high-speed core compressor is designed and fabricated based on aerodynamic similarity principles. This model is then tested at low speed where high-loss regions associated with three-dimensional endwall boundary layers, flow separation, leakage, and secondary flows can be located, detailed measurements made, and loss mechanisms determined with much greater accuracy and much lower cost and risk than is possible in small, high-speed compressors. Design modifications are made by using custom-tailored airfoils and vector diagrams, airfoil endbends, and modified wall geometries in the high-loss regions. The design improvements resulting in reduced loss or increased stall margin are then scaled to high speed. This paper describes the procedure and presents experimental results to show that in some cases endwall loss has been reduced by as much as 10 percent, flow separation has been reduced or eliminated, and stall margin has been substantially improved by using these techniques.
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Righi, Mauro, Vassilios Pachidis, László Könözsy, Fanzhou Zhao, and Mehdi Vahdati. "Three-dimensional low-order surge model for high-speed axial compressors." Journal of the Global Power and Propulsion Society 4 (December 18, 2020): 274–84. http://dx.doi.org/10.33737/jgpps/130790.
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Surge in modern aero-engines can lead to violent disruption of the flow, damage to the blade structures and eventually engine shutdown. Knowledge of unsteady performance and loading during surge is crucial for compressor design, however, the understanding and prediction capability for this phenomenon is still very limited. While useful for the investigation of specific cases, costly experimental tests and high-fidelity CFD simulations cannot be used routinely in the design process of compressor systems. There is therefore an interest in developing a low-order model which can predict compressor performance during surge with sufficient accuracy at significantly reduced computational cost. This paper describes the validation of an unsteady 3D through-flow code developed at Cranfield University for the low-order modelling of surge in axial compressors. The geometry investigated is an 8-stage rig representative of a modern aero-engine IP compressor. Two deep surge events are modelled at part speed and full speed respectively. The results are compared against high-fidelity, full annulus, URANS simulations conducted at Imperial College. Comparison of massflow, pressure and temperature time histories shows a close match between the low-order and the higher-fidelity methods. The low-order model is shown capable of predicting many transient flow features which were observed in the high-fidelity simulations, while reducing the computational cost by up to two orders of magnitude.
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Aligoodarz, MR, A. Mehrpanahi, M. Moshtaghzadeh, and A. Hashiehbaf. "Improved criteria for stall-free preliminary design of axial compressor of aero gas turbine engines." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 9 (August 24, 2018): 3286–97. http://dx.doi.org/10.1177/0954410018795538.
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A worldwide effort has been devoted to developing highly efficient and reliable gas turbine engines. There exist many prominent factors in the development of these engines. One of the most important features of the optimal design of axial flow compressors is satisfying the allowable range for various parameters such as flow coefficient, stage loading, the degree of reaction, De-Haller number, etc. But, there are some applicable cases that the mentioned criteria are exceeded. One of the most famous parameters is De-Haller number, which according to literature data should not be kept less than 0.72 in any stage of the axial compressor. A deep insight into the current small- or large-scale axial flow compressors shows that a discrepancy will occur among design criterion for De-Haller number and experimental measurements in which the De-Haller number is less than the design limit but no stall or surge is observed. In this paper, an improved formulation is derived based on one-dimensional modeling for predicting the stall-free design parameter ranges especially stage loading, flow coefficient, etc. for various combinations. It was found that the current criterion is much more accurate than the De-Haller criterion for design purposes.
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Hall, E. J. "Aerodynamic modelling of multistage compressor flow fields Part 1: Analysis of rotor-stator-rotor aerodynamic interaction." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 212, no. 2 (February 1, 1998): 77–89. http://dx.doi.org/10.1243/0954410981532153.
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The primary purpose of this study was to investigate improved numerical techniques for predicting flows through multistage compressors. The vehicle chosen for this study was the Pennsylvania State University Research Compressor (PSRC). The PSRC facility consists of a 3 1/2-stage axial flow compressor which shares design features which are consistent with embedded stages of modern gas turbine engine axial flow compressors. In Part 1 of this two-part paper, several computational fluid dynamics techniques were applied to predict both steady and unsteady flows through the PSRC facility. Interblade row coupling via a circumferentially averaged mixing-plane approach was employed for steady flow analysis. A mesh density sensitivity study was performed to define the minimum mesh requirements necessary to achieve reasonable agreement with the experimental data. Time-dependent flow predictions were performed using a time-dependent interblade row coupling technique. These calculations evaluated the aerodynamic interactions occurring between rotor 2, stator 2 and rotor 3 for the PSRC rig.
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Rechter, H., W. Steinert, and K. Lehmann. "Comparison of Controlled Diffusion Airfoils With Conventional NACA 65 Airfoils Developed for Stator Blade Application in a Multistage Axial Compressor." Journal of Engineering for Gas Turbines and Power 107, no. 2 (April 1, 1985): 494–98. http://dx.doi.org/10.1115/1.3239758.
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In their transonic cascade wind tunnel, DFVLR has done measurements on a conventional NACA 65, as well as on a controlled diffusion airfoil, designed for the same velocity triangle at supercritical inlet condition. These tested cascades represent the first stator hub section of a three-stage axial/one-stage radial combined compressor developed by MTU with the financial aid of the German Ministry of Research and Technology. One aspect of this project was the verification of the controlled diffusion concept for axial compressor blade design, in order to demonstrate the capabilities of some recent research results which are now available for industrial application. The stator blades of the axial compressor section were first designed using NACA 65 airfoils. In the second step, the controlled diffusion technique was applied for building a new stator set. Both stator configurations were tested in the MTU compressor test facility. Cascade and compressor tests revealed the superiority of the controlled diffusion airfoils for axial compressors. In comparison to the conventional NACA blades, the new blades obtained a higher efficiency. Furthermore, a closer matching of the compressor performance data to the design requirements was possible due to a more precise prediction of the turning angle.
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Lin, Feng, and Jingyi Chen. "Oscillatory Tip Leakage Flows and Stability Enhancement in Axial Compressors." International Journal of Rotating Machinery 2018 (June 6, 2018): 1–14. http://dx.doi.org/10.1155/2018/9076472.
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Rotating stall axial compressor is a difficult research field full of controversy. Over the recent decades, the unsteady tip leakage flows had been discovered and confirmed by several research groups independently. This paper summarizes the research experience on unsteady tip leakage flows and stability enhancement in axial flow compressors. The goal is to provide theoretical bases to design casing treatments and tip air injection for stall margin extension of axial compressor. The research efforts cover (1) the tip flow structure at near stall that can explain why the tip leakage flows go unsteady and (2) the computational and experimental evidences that demonstrate the axial momentum playing an important role in unsteady tip leakage flow. It was found that one of the necessary conditions for tip leakage flow to become unsteady is that a portion of the leakage flow impinges onto the pressure side of the neighboring blade near the leading edge. The impediment of the tip leakage flow against the main incoming flow can be measured by the axial momentum balance within the tip range. With the help of the theoretical progress, the applications are extended to various casing treatments and tip air recirculation.
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Song, Wei, Xi De Lai, Guang Fu Li, Wei Zhang, Xiao Ming Chen, and Zhen Lu. "Research on Reverse Engineering for Blades of Axial Compressors with Laser Scanner." Advanced Materials Research 774-776 (September 2013): 185–89. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.185.
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To acquire the digital model of axial compressors on the actual projects, a Reverse Engineering procedure of the blade was developed based on point cloud data acquired with the handy laser scanner. For meeting the requirements of geometric characteristics and aerodynamic optimization design and improving acquiring efficiency of point cloud data, the laser triangulation was employed and auxiliary plane and mark points were put on the inlet, outlet and tip of the blade. For solving the problem of low accuracy of fitting surface on the blade, an interactive dividing method of surface slices which based on the streamline, meridian line, contour and its extension line, was presented, it showed that reconstructed surface model can meet the actual projects needs. A completed set of RE technology for axial compressor blades has been developed, and it has been used in actual project combing with the maintenance of a large axial compressor blade.
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Broichhausen, K. D., H. E. Gallus, and R. Mo¨nig. "Off-Design Performance of Supersonic Compressors With Fixed and Variable Geometry." Journal of Turbomachinery 110, no. 3 (July 1, 1988): 312–21. http://dx.doi.org/10.1115/1.3262197.
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Regarding the extremely high pressure ratios of jet-engine compressors for the next decade, increasing interest belongs to the further development of supersonic compressors with supersonic relative flow at rotor inlet and supersonic absolute flow at stator inlet. In the past, different suitable design procedures for these components have been developed and tested successfully. However, there is a lack of information concerning the off-design performance of supersonic compressors. The present paper first systematically shows blading and flow path geometry of different experimentally investigated supersonic axial flow compressors. These investigations refer to combinations of characteristic rotors and stators with fixed and variable geometry. A comparison of these geometric data with the main characteristics of the flow pattern shows that, for the investigated stages, the three-dimensional passage geometry has an essential influence on the off-design performance. On the basis of this information semi-empirical models are established for a numerical description of the flow phenomena with predominant influence, as for example shock-, profile-, and endwall boundary layer losses and rotor-stator interactions. For the determination of the off-design performance, these models are incorporated into a streamline curvature calculation method. The computer model established is able to describe the off-design characteristics of the different investigated supersonic compressor stages in the most important operating range.
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Bhoyar, Suraj, Virendra Bhojwani, and Sudarshan Sanap. "Parametric Design and Comparative Analysis of a Special Purpose Flexure Spring." E3S Web of Conferences 170 (2020): 02013. http://dx.doi.org/10.1051/e3sconf/202017002013.
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Flexure springs play pivotal role to ensure reliability and durability of the cryocooler compressors. The critical application of flexure spring intends to eliminate the wear, frictional losses and significantly vibrations. A parameter study was performed considering the design variables of a flexure spring to meet the requirements of the cryocooler compressors viz. complexity of the geometric configuration, radial and axial stiffness, fatigue life, material, etc. The parametric design approach was deployed using finite element analysis (FEA), to validate the same by experimental data to analyse the performance of the flexure spring. This paper also presents a comparative analysis of the design variables in terms of axial and radial stiffness, induced stress as well as the manufacturing methods’ considerations to optimize the design of a special purpose flexure spring for the cryocooler compressors. Furthermore, experimental study of the flexure spring was carried out in order to maximize the stroke.
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Leylek, J. H., and D. C. Wisler. "Mixing in Axial-Flow Compressors: Conclusions Drawn From Three-Dimensional Navier–Stokes Analyses and Experiments." Journal of Turbomachinery 113, no. 2 (April 1, 1991): 139–56. http://dx.doi.org/10.1115/1.2929069.
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Extensive numerical analyses and experiments have been conducted to understand mixing phenomena in multistage, axial-flow compressors. For the first time in the literature the following are documented: Detailed three-dimensional Navier–Stokes solutions, with high order turbulence modeling, are presented for flow through a compressor vane row at both design and off-design (increased) loading; comparison of these computations with detailed experimental data show excellent agreement at both loading levels; the results are then used to explain important aspects of mixing in compressors. The three-dimensional analyses show the development of spanwise (radial) and circumferential flows in the stator and the change in location and extent of separated flow regions as loading increases. The numerical solutions support previous interpretations of experimental data obtained on the same blading using the ethylene tracer-gas technique and hot-wire anemometry. These results, plus new tracer-gas data, show that both secondary flow and turbulent diffusion are mechanisms responsible for both spanwise and circumferential mixing in axial-flow compressors. The relative importance of the two mechanisms depends upon the configuration and loading levels. It appears that using the correct spanwise distributions of time-averaged inlet boundary conditions for three-dimensional Navier–Stokes computations enables one to explain much of the flow physics for this stator.
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Howard, M. A., and S. J. Gallimore. "Viscous Throughflow Modeling for Multistage Compressor Design." Journal of Turbomachinery 115, no. 2 (April 1, 1993): 296–304. http://dx.doi.org/10.1115/1.2929235.
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An existing throughflow method for axial compressors, which accounts for the effects of spanwise mixing using a turbulent diffusion model, has been extended to include the viscous shear force on the endwall. The use of a shear force, consistent with a no-slip condition, on the annulus walls in the throughflow calculations allows realistic predictions of the velocity and flow angle profiles near the endwalls. The annulus wall boundary layers are therefore incorporated directly into the throughflow prediction. This eliminates the need for empirical blockage factors or independent annulus boundary layer calculations. The axisymmetric prediction can be further refined by specifying realistic spanwise variations of loss coefficient and deviation to model the three-dimensional endwall effects. The resulting throughflow calculation gives realistic predictions of flow properties across the whole span of a compressor. This is confirmed by comparison with measured data from both low and high-speed multistage machines. The viscous throughflow method has been incorporated into an axial compressor design system. The method predicts the meridional velocity defects in the endwall region and consequently blading can be designed that allows for the increased incidence, and low dynamic head, near the annulus walls.
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Borovkov, A. I., Yu B. Galerkin, O. A. Solovieva, A. A. Drozdov, A. F. Rekstin, V. B. Semenovsky, and P. N. Brodnev. "Development of mathematical model and computer program for primary design of transonic axial compressor." Omsk Scientific Bulletin. Series Aviation-Rocket and Power Engineering 4, no. 4 (2020): 16–27. http://dx.doi.org/10.25206/2588-0373-2020-4-4-16-27.
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The mathematical model underlying the program for calculating and designing axial compressors is presented. The process of calculating the pressure loss in the elements of the axial compressor stage flow path is described. The loss coefficient consists of losses on the limiting surfaces, secondary losses and profile losses. The effect of roughness on the pressure loss is taken into account by introducing the corresponding empirical coefficient. An algorithm for calculating the blades and vanes angles of the impeller and the guide apparatus is presented by calculating the incidence angle and the lag angle of the flow. The flow lag angle is the sum of the lag angle of the flow on the profile and the lag angle due to viscous flow on the limiting surfaces
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Mo¨nig, Reinhard, Frank Mildner, and Ralf Ro¨per. "Viscous-Flow Two-Dimensional Analysis Including Secondary Flow Effects." Journal of Turbomachinery 123, no. 3 (February 1, 2000): 558–67. http://dx.doi.org/10.1115/1.1370167.
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During the last few decades extremely powerful Quasi-three-dimensional (3D) codes and fully 3D Navier-Stokes solvers have been developed and successfully utilized in the design process and optimization of multistage axial-flow compressors. However, most of these methods proved to be difficult in handling and extremely time consuming. Due to these disadvantages, the primary stage design and stage matching as well as the off-design analysis is nowadays still based on fast 2D methods incorporating loss-, deviation- and end wall modeling. Only the detailed 3D optimization is normally performed by means of advanced 3D methods. In this paper a fast and efficient 2D calculation method is presented, which already in the initial design phase of multistage axial flow compressors, considers the influence of hub leakage flows, tip clearance effects, and other end wall flow phenomena. The method is generally based on the fundamental approach by Howard and Gallimore (1992). In order to allow a more accurate prediction of skewed and nondeveloped boundary layers in turbomachines, an improved theoretical approach was implemented. Particularly the splitting of the boundary layers into an axial and tangential component proved to be necessary in order to account for the change between rotating and stationary end walls. Additionally, a new approach is used for the prediction of the viscous end wall zones including hub leakage effects and strongly skewed boundary layers. As a result, empirical correlations for secondary flow effects are no longer required. The results of the improved method are compared with conventional 2D results including 3D loss- and deviation-models, with experimental data of a three-stage research compressor of the Institute for Jet Propulsion and Turbomachinery of the Technical University of Aachen and with 3D Navier-Stokes solutions of the V84.3A compressor and of a multistage Siemens research compressor. The results obtained using the new method show a remarkable improvement in comparison with conventional 2D methods. Due to the high quality and the extremely short computation time, the new method allows an overall viscous design of multistage compressors for heavy duty gas turbines and aeroengine applications.
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Smith,, Leroy H. "Axial Compressor Aerodesign Evolution at General Electric." Journal of Turbomachinery 124, no. 3 (July 1, 2002): 321–30. http://dx.doi.org/10.1115/1.1486219.
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This paper traces the origins of the GE Design System and how it has evolved from early methods to underlie and supplement present CFD methods, which are not themselves discussed herein. The two main elements of the detailed aero design process are vector diagram establishment and airfoil design. Their evolution is examined, and examples of how they were used to design some early GE compressors of interest are given. By the late 1950s, some transonic airfoil shapes were being custom tailored using internal blade station data from more complete radial equilibrium solutions. In the 1960s, rules for shaping transonic passages were established, and by the 1970s, custom tailoring was done for subsonic blading as well. The preliminary design layout process for a new compressor is described. It involves selecting an annulus shape and blading overall proportions that will allow a successful detailed design to follow. This requires establishment of stage loading limits that permit stall-free operation, and an efficiency potential prediction method for state-of-the-art blading. As design methods evolved, the newer approaches were calibrated with data-match experience, a process that is expected to always be needed.
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Schrapp, H., U. Stark, and H. Saathoff. "Unsteady behaviour of the tip clearance vortex in a rotor equivalent compressor cascade." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 223, no. 6 (July 6, 2009): 635–43. http://dx.doi.org/10.1243/09576509jpe816.
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From earlier experimental investigations in a single-stage axial-flow pump and different numerical calculations of the flow in single-stage axial-flow compressors, it is known that vortex breakdown of the tip clearance vortex can take place in turbomachines, although an experimental proof for subsonic compressors is lacking. Vortex breakdown, if existent, is a source of high instability in the sensitive tip region of axial-flow pumps and compressors and will also play an important role in the stall inception process. Therefore, the flow in a linear compressor cascade with a 3 per cent tip clearance to one side has been investigated at different flow angles from the design point up to the stability limit of the cascade. The cascade resembles the tip section of a single-stage, axial-flow, low-speed compressor that is also in use at the Technical University of Braunschweig. The measuring techniques used were (a) a commercial particle image velocimetry (PIV) system and (b) a pressure measuring system with several flush mounted high-response pressure transducers at selected locations where the vortex was expected. As the cascade approaches its stall limit, the analysis of the pressure signals in the frequency domain revealed a bump of increased amplitude at a certain non-dimensional frequency for some of the measuring positions. The measuring positions that exhibited the bump correlated very well with a paraboloid-shaped region of high standard deviation enveloping an area of very low momentum fluid. It is shown that the frequency of the striking bump corresponds to the rotational frequency of the vortex calculated from the PIV measurements.
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Rakhmanina, L. A., A. V. Zuev, A. Yu Petrov, A. A. Aksenov, and Minh Hai Nguyen. "The investigation of absolute flow non-uniform velocity distributions influence at the centrifugal compressor axial radial impeller inlet using numerical calculation methods in ANSYS CFX." E3S Web of Conferences 140 (2019): 05008. http://dx.doi.org/10.1051/e3sconf/201914005008.
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Currently, methods of numerical modelling are widely used. They are especially widely used in the design of turbo compressors. For the specific task of designing new flowing parts of a centrifugal compressor, it is not recommended to deviate from the canonical design techniques, but it is preferable to supplement them with numerical methods. This article is devoted to the end two-element stage investigation of a centrifugal compressor with an axial radial impeller; the stage main dimensions were obtained using the method of V.F. Rice. In order to obtain the necessary pressure characteristics and determine the dependence for the absolute velocity non-uniform distribution at the inlet to the axial radial impeller, the flow path main dimensions were optimized using numerical calculation methods. The calculation was performed using the SST turbulence model using computational gas dynamics methods in the ANSYS CFX software environment. Based on the optimization results, five compressor designs and corresponding characteristics were obtained. The absolute velocity distribution nature at the inlet to the centrifugal compressor axial radial impeller for five flow path variants is investigated. Empirical dependences are obtained for the deviation of the absolute velocity at the inlet in the hub section axial radial impeller and the absolute velocity deviation at the shroud from the absolute velocity at the average diameter based on the results of a numerical experiment. Recommendations are made for further absolute velocity distributions investigating at the inlet to the compressor impeller.
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Aungier,, RH, and S. Farokhi,. "Axial-Flow Compressors: A Strategy for Aerodynamic Design and Analysis." Applied Mechanics Reviews 57, no. 4 (July 1, 2004): B22. http://dx.doi.org/10.1115/1.1786589.
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Fre´chette, L. G., O. G. McGee, and M. B. Graf. "Tailored Structural Design and Aeromechanical Control of Axial Compressor Stall—Part II: Evaluation of Approaches." Journal of Turbomachinery 126, no. 1 (January 1, 2004): 63–72. http://dx.doi.org/10.1115/1.1644556.
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A theoretical evaluation was conducted delineating how aeromechanical feedback control can be utilized to stabilize the inception of rotating stall in axial compressors. Ten aeromechanical control methodologies were quantitatively examined based on the analytical formulations presented in the first part of this paper. The maximum operating range for each scheme is determined for optimized structural parameters, and the various schemes are compared. The present study shows that the most promising aeromechanical designs and controls for a class of low-speed axial compressors were the use of dynamic fluid injection. Aeromechanically incorporating variable duct geometries and dynamically re-staggered IGV and rotor blades were predicted to yield less controllability. The aeromechanical interaction of a flexible casing wall was predicted to be destabilizing, and thus should be avoided by designing sufficiently rigid structures to prevent casing ovalization or other structurally induced variations in tip clearance. Control authority, a metric developed in the first part of this paper, provided a useful interpretation of the aeromechanical damping of the coupled system. The model predictions also show that higher spatial modes can become limiting with aeromechanical feedback, both in control of rotating stall as well as in considering the effects of lighter, less rigid structural aeroengine designs on compressor stability.
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Shi, Hengtao. "A Parametric Blade Design Method for High-Speed Axial Compressor." Aerospace 8, no. 9 (September 18, 2021): 271. http://dx.doi.org/10.3390/aerospace8090271.
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The blade geometry design method is an important tool to design high performance axial compressors, expected to have large design space while limiting the quantity of design variables to a suitable level for usability. However, the large design space tends to increase the quantity of the design variables. To solve this problem, this paper utilizes the normalization and subsection techniques to develop a geometry design method featuring flexibility and local adjustability with limited design variables for usability. Firstly, the blade geometry parameters are defined by using the normalization technique. Then, the normalized camber angle f1(x) and thickness f2(x) functions are proposed with subsection techniques used to improve the design flexibility. The setting of adjustable coefficients acquires the local adjustability of blade geometry. Considering the usability, most of the design parameters have clear, intuitive meanings to make the method easy to use. To test this developed geometry design method, it is applied in the design of a transonic, two flow-path axial fan component for an aero engine. Numerical simulations indicate that the designed transonic axial fan system achieves good efficiency above 0.90 for the entire main-flow characteristic and above 0.865 for the bypass flow characteristic, while possessing a sufficiently stable operation range. This indicates that the developed design method has a large design space for containing the good performance compressor blade of different inflow Mach numbers, which is a useful platform for axial-flow compressor blade design.
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Novecosky, T. "Axial Inlet Conversion to a Centrifugal Compressor With Magnetic Bearings." Journal of Engineering for Gas Turbines and Power 116, no. 1 (January 1, 1994): 152–55. http://dx.doi.org/10.1115/1.2906784.
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NOVA’s Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, United States, and British Columbia. There is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level that allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).
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Dong, Zhaohui, Jinxin Cheng, Tian Liu, Gaolu Si, and Buchuan Ma. "A Novel Surface Parametric Method and Its Application to Aerodynamic Design Optimization of Axial Compressors." Processes 9, no. 7 (July 16, 2021): 1230. http://dx.doi.org/10.3390/pr9071230.
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A novel parametric control method for the compressor blade, the full-blade surface parametric method, is proposed in this paper. Compared with the traditional parametric method, the method has good surface smoothness and construction convenience while maintaining low-dimensional characteristics, and compared with the semi-blade surface parametric method, the proposed method has a larger degree of geometric deformation freedom and can account for changes in both the suction surface and pressure surface. Compared with the semi-blade surface parametric method, the method only has four more control parameters for each blade, so it does not significantly increase the optimization time. The effectiveness of this novel parametric control method has been verified in the aerodynamic optimization field of compressors by an optimization case of Stage35 (a single-stage transonic axial compressor) under multi-operating conditions. The optimization case has brought the following results: the adiabatic efficiency of the optimized blade at design speed is 1.4% higher than that of the original one and the surge margin 2.9% higher, while at off-design speed, the adiabatic efficiency is improved by 0.6% and the surge margin by 1.3%.
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Roberts, W. B., G. K. Serovy, and D. M. Sandercock. "Design Point Variation of Three-Dimensional Loss and Deviation for Axial Compressor Middle Stages." Journal of Turbomachinery 110, no. 4 (October 1, 1988): 426–33. http://dx.doi.org/10.1115/1.3262215.
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Three-dimensional spanwise pressure loss and flow angle deviation variations have been deduced from NASA, university, and industrial sources from middle-stage research compressors operating near design point. These variations are taken as the difference above or below that predicted by blade element theory at any spanwise location. It was observed that the magnitude of the three-dimensional loss and deviation in the endwall regions is affected by hub and casing boundary layer thickness, camber, solidity, and blade channel aspect ratio for stators and rotor hubs. Rotor tip variations were found to depend on casing boundary layer thickness and tip clearance. Simple design point loss models derived from these data can aid in the design of axial compressor middle stages.
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Eisenberg, B. "Development of a New Front Stage for an Industrial Axial Flow Compressor." Journal of Turbomachinery 116, no. 4 (October 1, 1994): 597–604. http://dx.doi.org/10.1115/1.2929449.
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Industrial axial flow compressors are specially designed to achieve a wide operating range. The analysis of an existing six-stage axial flow research compressor indicated that the front stage could be improved significantly using modern design technique. To demonstrate the advantages of such a technique a redesign of the current front stage was conducted. By controlling the diffusion inside the blade sections with an inverse design method, loading was enlarged. Higher loading normally results in a reduction of profile incidence range. For compensation a wide chord application was chosen. Compared to the original compressor version, experiments resulted in steeper characteristic curves together with larger usable operating range. Keeping the same outer and inner diameter, mass flow was increased by 6 percent. Measurements of performance curves with variable speed and for guide vane control are presented. Theoretical calculations achieve a high degree of agreement with measured performance.
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Zheng, Xinqian, Chuang Ding, and Yangjun Zhang. "Influence of different loads on the stresses of multistage axial compressor rotors." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 5 (April 19, 2016): 787–98. http://dx.doi.org/10.1177/0954410016642461.
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Multistage axial compressors are widely used in the gas turbine engines. The strength of rotors is one of the key factors for the reliability of multistage axial compressors. The stresses of rotors at real working conditions can be caused by the centrifugal load, thermal load, and aerodynamic load. It is important to figure out the roles and the mechanism of the three kinds of loads in the stresses generating process. In this paper, the stresses of rotors in a typical five-stage axial compressor are calculated with different kinds of loads by solid–fluid coupling method. The results show that the proportion of the stress caused by centrifugal load is more than 80% of the total stress, which is dominant. The maximum proportion of the stress caused by thermal load is about 20% of the total stress at the front stages. However, the influence of thermal load is quite different from the first stage to the last stage. It is surprising that thermal load can decrease the stresses of the last stage rotor, which is mainly because of the variation of radial temperature gradient at disks for different stages. The proportion of the stress caused by aerodynamic load is usually less than 4%, and it tends to make the stresses at the suction side of the blades lower and enlarge it at the pressure side. According to the above results, centrifugal load is necessary of consideration at the conceptual design phase for the multistage axial compressor rotors. At preliminary three-dimensional design phase, centrifugal load and thermal load should be considered together. At optimized three-dimensional design phase, aerodynamic load cannot be neglected and all the three loads should be considered.
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Yang, Chen, Hu Wu, Jinguang Yang, and Michele Ferlauto. "Time-marching throughflow analysis of multistage axial compressors based on a novel inviscid blade force model." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 14 (April 2019): 5239–52. http://dx.doi.org/10.1177/0954410019840588.
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A time-marching throughflow method for the off-design performance analysis of axial compressors is described. The method is based on the Euler equations, and a new inviscid blade force model is proposed in order to achieve desired flow deflection. The flow discontinuity problems at the leading and trailing edges are tackled by automatic correction of blade mean surface using cubic spline interpolation. Empirical loss models have been integrated into the throughflow model in order to simulate the viscous force effects in the real three-dimensional flow. Two test cases have been presented to validate the throughflow model, including the transonic fan rotor – NASA Rotor 67 working at a near-peak-efficiency point and a 1.5-stage high-speed axial compressor with inlet guide vane operating at 68% nominal speed. Reasonable flow parameters distributions have been obtained in the Rotor 67 fan calculating results, and accurate overall performance characteristics have also been predicted at the strong off-design condition for the 1.5-stage axial compressor. The CPU time of both cases cost less than one minute at one operating point. The results indicate that the developed time-marching throughflow model is effective and efficient in the turbomachinery performance analysis.
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Steinert, W., B. Eisenberg, and H. Starken. "Design and Testing of a Controlled Diffusion Airfoil Cascade for Industrial Axial Flow Compressor Application." Journal of Turbomachinery 113, no. 4 (October 1, 1991): 583–90. http://dx.doi.org/10.1115/1.2929119.
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Similar to jet engine development, modern design methods are used today to improve the performance of industrial compressors. In order to verify the loading limits, a cascade profile representative for the first rotor hub section of an industrial compressor has been designed by optimizing the suction surface velocity distribution using a direct boundary layer calculation method. The blade shape was computed with an inverse full potential code and the resulting cascade was tested in a cascade wind tunnel. The experimental results confirmed the design intent and resulted in a low loss coefficient of 1.8 percent at design condition and an incidence range of nearly 12 deg (4 percent loss level) at an inlet Mach number of 0.62.
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Amin Mobarak, Mostafa Shawky Abdel Moez, and Shady Ali. "Quasi Three-Dimensional Design for a Novel Turbo-Vapor Compressor and the Last Stage of a Low-Pressure Steam Turbine." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 85, no. 2 (August 5, 2021): 1–13. http://dx.doi.org/10.37934/arfmts.85.2.113.
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Turbo-vapor compressors (TVCs) are used to create a vacuum pressure in the evaporator of a novel combined cycle for electricity and freshwater production invented by Amin Mobarak. A novel design conceived of a TVC is introduced to increase the efficiency, allowable mass flow rate and reduce costs and losses. The system consists of a single axial compressor rotor followed by a single axial turbine rotor, which drives the upstream compressor, allowing high flow rates. A quasi-3D design is carried out for the TVC to calculate the flow velocity components and angles and ensure that the turbo-vapor turbine work is equal to the turbo-vapor compressor work. A preliminary design of the low-pressure power turbine (LPT) is done to examine the size and number of stages. The (LPT) size is twice the size of TVC at typical cycle operating conditions. A three-stage design is the most appropriate choice for the number of stages. It satisfies the accelerating relative flow condition at the last stage over a range of flow coefficients. A quasi-3D design is carried out for the LPT's last stage to ensure a multi-stage power turbine's safe design.
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Song, Wei, Xi De Lai, Wei Zhang, Zhen Lu, and Xiao Ming Chen. "Research on Reverse Engineering for Blades of Axial Flow Compressors Based on Parameterization." Advanced Materials Research 813 (September 2013): 3–6. http://dx.doi.org/10.4028/www.scientific.net/amr.813.3.
Full textAbstract:
To acquire the digital model of axial compressors on the actual projects, a Reverse Engineering procedure of the blade which has high accuracy and efficiency based on Parametric Modeling was developed. To meet the requirements of geometric characteristics and aerodynamic optimization design and accuracy of overall blade, a method of blade-measuring path planning based on curves of cross sections and blade body surfaces was presented. For solving the problems of difficulty in the definition and fitting in primary parametric surfaces and connections between them, a parametric surface definition method of typical axial compressors blade based on blade geometry was presented and the connections were fit with a process of primary parametric surface boundary-splicing surface generation. Finally, an example of Reverse Engineering for blades of axial flow compressors based on parameterization was given.