Relevant bibliographies by topics / Tip clearance measurements in turbomachines

Academic literature on the topic 'Tip clearance measurements in turbomachines'

Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Tip clearance measurements in turbomachines.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Tip clearance measurements in turbomachines"

1

Kameier, F., and W. Neise. "Experimental Study of Tip Clearance Losses and Noise in Axial Turbomachines and Their Reduction." Journal of Turbomachinery 119, no. 3 (July 1, 1997): 460–71. http://dx.doi.org/10.1115/1.2841145.

Full text
Abstract:
An experimental study is described to investigate the negative effects of the tip clearance gap on the aerodynamic and acoustic performance of axial turbomachines. In addition to the increased broadband levels reported in the literature when the tip clearance is enlarged, significant level increases were observed within narrow frequency bands below the blade passing frequency. Measurements of the pressure and velocity fluctuations in the vicinity of the blade tips reveal that the tip clearance noise is associated with a rotating flow instability at the blade tip, which in turn is only present under reversed flow conditions in the tip clearance gap. A turbulence generator inserted into the tip clearance gap is found to be effective in eliminating the tip clearance noise and in improving the aerodynamic performance.
APA, Harvard, Vancouver, ISO, and other styles
2

Jia, Bing Hui, and Xiao Dong Zhang. "Study on Effect of Rotor Vibration on Tip Clearance Variation and Fast Active Control of Tip Clearance." Advanced Materials Research 139-141 (October 2010): 2469–72. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.2469.

Full text
Abstract:
The tip clearance flow of axial turbomachines is important for their aerodynamic and maneuver performance. And the tip clearance gap leakage flow is of continuing concern in reducing efficiency losses that occur within turbines. In order to gain significant reductions in emissions and specific fuel consumption as well as dramatic improvements in operating efficiency and increased service life of aero-engine, variation mechanism of blade tip clearance was analyzed and the equation of dynamic clearance was shown firstly, then the effect of rotor vibration in clearance variation which include flight loads and engine loads was studied in this paper; based on the dynamic measurements of blade tip clearance, a method that ensure tip clearance at optimal state in given mission profile through active rotor vibration control and active tip clearance control was presented. Besides, fuzzy control theory was used to solve the high nonlinear variation of tip clearance. The analysis result shows that this technique is useful.
APA, Harvard, Vancouver, ISO, and other styles
3

Dambach, R., H. P. Hodson, and I. Huntsman. "1998 Turbomachinery Committee Best Paper Award: An Experimental Study of Tip Clearance Flow in a Radial Inflow Turbine." Journal of Turbomachinery 121, no. 4 (October 1, 1999): 644–50. http://dx.doi.org/10.1115/1.2836716.

Full text
Abstract:
This paper describes an experimental investigation of tip clearance flow in a radial inflow turbine. Flow visualization and static pressure measurements were performed. These were combined with hot-wire traverses into the tip gap. The experimental data indicate that the tip clearance flow in a radial turbine can be divided into three regions. The first region is located at the rotor inlet, where the influence of relative casing motion dominates the flow over the tip. The second region is located toward midchord, where the effect of relative casing motion is weakened. Finally, a third region exists in the exducer, where the effect of relative casing motion becomes small and the leakage flow resembles the tip flow behavior in an axial turbine. Integration of the velocity profiles showed that there is little tip leakage in the first part of the rotor because of the effect of scraping. It was found that the bulk of tip leakage flow in a radial turbine passes through the exducer. The mass flow rate, measured at four chordwise positions, was compared with a standard axial turbine tip leakage model. The result revealed the need for a model suited to radial turbines. The hot-wire measurements also indicated a higher tip gap loss in the exducer of the radial turbine. This explains why the stage efficiency of a radial inflow turbine is more affected by increasing the radial clearance than by increasing the axial clearance.
APA, Harvard, Vancouver, ISO, and other styles
4

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.

Full text
Abstract:
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.
APA, Harvard, Vancouver, ISO, and other styles
5

Van Zante, Dale E., Anthony J. Strazisar, Jerry R. Wood, Michael D. Hathaway, and Theodore H. Okiishi. "Recommendations for Achieving Accurate Numerical Simulation of Tip Clearance Flows in Transonic Compressor Rotors." Journal of Turbomachinery 122, no. 4 (February 1, 1999): 733–42. http://dx.doi.org/10.1115/1.1314609.

Full text
Abstract:
The tip clearance flows of transonic compressor rotors are important because they have a significant impact on rotor and stage performance. A wall-bounded shear layer formed by the relative motion between the overtip leakage flow and the shroud wall is found to have a major influence on the development of the tip clearance flow field. This shear layer, which has not been recognized by earlier investigators, impacts the stable operating range of the rotor. Simulation accuracy is dependent on the ability of the numerical code to resolve this layer. While numerical simulations of these flows are quite sophisticated, they are seldom verified through rigorous comparisons of numerical and measured data because these kinds of measurements are rare in the detail necessary to be useful in high-speed machines. In this paper we compare measured tip-clearance flow details (e.g., trajectory and radial extent) with corresponding data obtained from a numerical simulation. Laser-Doppler Velocimeter (LDV) measurements acquired in a transonic compressor rotor, NASA Rotor 35, are used. The tip clearance flow field of this transonic rotor is simulated using a Navier–Stokes turbomachinery solver that incorporates an advanced k–ε turbulence model derived for flows that are not in local equilibrium. A simple method is presented for determining when the wall-bounded shear layer is an important component of the tip clearance flow field. [S0889-504X(00)02504-6]
APA, Harvard, Vancouver, ISO, and other styles
6

Kunz, R. F., B. Lakshminarayana, and A. H. Basson. "Investigation of Tip Clearance Phenomena in an Axial Compressor Cascade Using Euler and Navier–Stokes Procedures." Journal of Turbomachinery 115, no. 3 (July 1, 1993): 453–67. http://dx.doi.org/10.1115/1.2929274.

Full text
Abstract:
Three-dimensional Euler and full Navier–Stokes computational procedures have been utilized to simulate the flow field in an axial compressor cascade with tip clearance. An embedded H-grid topology was utilized to resolve the flow physics in the tip gap region. The numerical procedure employed is a finite difference Runge-Kutta scheme. Available measurements of blade static pressure distributions along the blade span, dynamic pressure and flow angle in the cascade outlet region, and spanwise distributions of blade normal force coefficient and circumferentially averaged flow angle are used for comparison. Several parameters that were varied in the experimental investigations were also varied in the computational studies. Specifically, measurements were taken and computations were performed on the configuration with and without: tip clearance, the presence of an endwall, inlet endwall total pressure profiles and simulated relative casing rotation. Additionally, both Euler and Navier–Stokes computations were performed to investigate the relative performance of these approaches in reconciling the physical phenomena considered. Results indicate that the Navier–Stokes procedure, which utilizes a low Reynolds number k–ε model, captures a variety of important physical phenomena associated with tip clearance flows with good accuracy. These include tip vortex strength and trajectory, blade loading near the tip, the interaction of the tip clearance flow with passage secondary flow, and the effects of relative endwall motion. The Euler computation provides good but somewhat diminished accuracy in resolution of some of these clearance phenomena. It is concluded that the level of modeling embodied in the present approach is sufficient to extract much of the tip region flow field information useful to designers of turbomachinery.
APA, Harvard, Vancouver, ISO, and other styles
7

Farrell, K. J., and M. L. Billet. "A Correlation of Leakage Vortex Cavitation in Axial-Flow Pumps." Journal of Fluids Engineering 116, no. 3 (September 1, 1994): 551–57. http://dx.doi.org/10.1115/1.2910312.

Full text
Abstract:
Tip clearance flow in turbomachinery can lead to losses in efficiency and stall margin. In liquid handling turbomachinery, the vortical flow field, formed from the interaction of the leakage flow with the through-flow, is subject to cavitation. Furthermore, this flow field is complex and not well understood. A correlation of variables which predict the vortex minimum pressure has been formulated. Measurements of the important variables for this correlation have been made on a high Reynolds number (3 × 106) axial-flow test rig. The correlation has been applied to the measured data and other data sets from the literature with good agreement. An optimum tip clearance has been theoretically identified as experiments have shown. Observations of cavitation indicate a second vortex originating along the suction side trailing edge.
APA, Harvard, Vancouver, ISO, and other styles
8

Dawes, W. N. "A Numerical Analysis of the Three-Dimensional Viscous Flow in a Transonic Compressor Rotor and Comparison With Experiment." Journal of Turbomachinery 109, no. 1 (January 1, 1987): 83–90. http://dx.doi.org/10.1115/1.3262074.

Full text
Abstract:
The numerical analysis of highly loaded transonic compressors continues to be of considerable interest. Although much progress has been made with inviscid analyses, viscous effects can be very significant, especially those associated with shock–boundary layer interactions. While inviscid analyses have been enhanced by the interactive inclusion of blade surf ace boundary layer calculations, it may be better in the long term to develop efficient algorithms to solve the full three-dimensional Navier–Stokes equations. Indeed, it seems that many phenomena of key interest, like tip clearance flows, may only be accessible to a Navier–Stokes solver. The present paper describes a computer program developed for solving the three-dimensional viscous compressible flow equations in turbomachine geometries. The code is applied to the study of the flowfield in an axial-flow transonic compressor rotor with an attempt to resolve the tip clearance flow. The predicted flow is compared with laser anemometry measurements and good agreement is found.
APA, Harvard, Vancouver, ISO, and other styles
9

Geng, Linlin, Desheng Zhang, Jian Chen, and Xavier Escaler. "Large-Eddy Simulation of Cavitating Tip Leakage Vortex Structures and Dynamics around a NACA0009 Hydrofoil." Journal of Marine Science and Engineering 9, no. 11 (October 30, 2021): 1198. http://dx.doi.org/10.3390/jmse9111198.

Full text
Abstract:
The tip leakage vortex (TLV) has aroused great concern for turbomachine performance, stability and noise generation as well as cavitation erosion. To better understand structures and dynamics of the TLV, large-eddy simulation (LES) is coupled with a homogeneous cavitation model to simulate the cavitation flow around a NACA0009 hydrofoil with a given clearance. The numerical results are validated by comparisons with experimental measurements. The results demonstrate that the present LES can well predict the mean behavior of the TLV. By visualizing the mean streamlines and mean streamwise vorticity, it shows that the TLV dominates the end-wall vortex structures, and that the generation and evolution of the other vortices are found to be closely related to the development of the TLV. In addition, as the TLV moves downstream, it undergoes an interesting progression, i.e., the vortex core radius keeps increasing and the axial velocity of vortex center experiences a conversion from jet-like profile to wake-like profile.
APA, Harvard, Vancouver, ISO, and other styles
10

Vazquez Gonzalez, Adrián, Andrés Meana-Fernández, and Jesús Manuel Fernández. "Stator–rotor interaction in the tip leakage flow of an inlet vaned low-speed axial fan." International Journal of Numerical Methods for Heat & Fluid Flow 30, no. 10 (January 11, 2020): 4425–52. http://dx.doi.org/10.1108/hff-07-2019-0593.

Full text
Abstract:
Purpose The purpose of the paper is to quantify the impact of the non-uniform flow generated by the upstream stator on the generation and convection of the tip leakage flow (TLF) structures in the passages of the rotor blades in a low-speed axial fan. Design/methodology/approach A full three dimensional (3D)-viscous unsteady Reynolds-averaged Navier-stokes (RANS) (URANS) simulation of the flow within a periodic domain of the axial stage has been performed at three different flow rate coefficients (φ = 0.38, 0.32, 0.27) using ReNormalization Group k-ε turbulence modelling. A typical tip clearance of 2.3 per cent of the blade span has been modelled on a reduced domain comprising a three-vaned stator and a two-bladed rotor with circumferential periodicity. A non-conformal grid with hybrid meshing, locally refined O-meshes on both blades and vanes walls with (100 × 25 × 80) elements, a 15-node meshed tip gap and circumferential interfaces for sliding mesh computations were also implemented. The unsteady motion of the rotor has been covered with 60 time steps per blade event. The simulations were validated with experimental measurements of the static pressure in the shroud of the blade tip region. Findings It has been observed that both TLF and intensities of the tip leakage vortex (TLV) are significantly influenced by upstream stator wakes, especially at nominal and partial load conditions. In particular, the leakage flow, which represents 12.4 per cent and 11.3 per cent of the working flow rate, respectively, has shown a clear periodic fluctuation clocked with the vane passing period in the relative domain. The periodic fluctuation of the TLF is in the range of 2.8-3.4 per cent of the mean value. In addition, the trajectory of the tip vortex is also notably perturbed, with root-mean squared fluctuations reaching up to 18 per cent and 6 per cent in the regions of maximum interaction at 50 per cent and 25 per cent of the blade chord for nominal and partial load conditions, respectively. On the contrary, the massive flow separation observed in the tip region of the blades for near-stall conditions prevents the formation of TLV structures and neglects any further interaction with the upstream vanes. Research limitations/implications Despite the increasing use of large eddy simulation modelling in turbomachinery environments, which requires extremely high computational costs, URANS modelling is still revealed as a useful technique to describe highly complex viscous mechanisms in 3D swirl flows, such as unsteady tip flow structures, with reasonable accuracy. Originality/value The paper presents a validated numerical model that simulates the unsteady response of the TLF to upstream perturbations in an axial fan stage. It also provides levels of instabilities in the TLV derived from the deterministic non-uniformities associated to the vane wakes.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Tip clearance measurements in turbomachines"

1

Cho, Donald L. (Donald Lee). "Effect of vortex core stagnation pressure on tip clearance flow blockage in turbomachines." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/47391.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ekong, Godwin I. "Tip clearance control concepts in gas turbine H.P. compressors." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/48906/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Lewis, Daniel Joseph. "Tip clearance and angle of attack effects upon the unsteady response of a vibrating flat plate in crossflow /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06112009-063924/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Lewis, Daniel Russell. "Tip clearance and angle of attack effects upon the unsteady response of a vibrating flat plate in crossflow." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/43198.

Full text
Abstract:

The influence of tip clearance and angle of attack upon the mid-span unsteady pressure response of a vibrating flat plate was investigated experimentally. Unsteady pressure measurements were taken for a variety of incidence angles, vibration frequencies and tip clearances over a Mach number range of 0.2 to 0.6.

It was found that changes in tip clearance had an effect on measured pressure fluctuations at higher angles of attack and larger Mach numbers. It was also observed that the amplitude of the unsteady pressure increased as the incidence angle was increased.

The plate was mechanically induced to oscillate in translation, simulating the flISt bending mode. Averaged Fast Fourier Transforms were used to determine pressure oscillation amplitudes and phase lags with respect to the plate motion.


Master of Science
APA, Harvard, Vancouver, ISO, and other styles
5

Chen, Jian Yu, and 陳建宇. "Study of the Tip Clearance and Dynamical Measurements for Turbomachinery Using Non-contact Probes." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/94253174346165328725.

Full text
Abstract:
碩士
國立中興大學
機械工程學系
91
Abstract This study sets up a non-contact measurement system with light probes for revealing vibration characteristics of rotor blades by using blade tip clearance. The two-parameter method in conjunction with measurements on a small fan is studied. The study finds an analytical relationship for the two-parameter method based on the linear vibration equation. This analytical result describes the relation between axis ratio of the blade dynamic ellipse and phase difference of the probes. The speed of fan is in the range from 800 to 2500 rpm for the measurements of the tip clearance for dynamic analysis of the blade vibrations. Experiments include the one-probe method and two-probe method. The one-probe method measures vibration of an arbitrary blade with one probe located at a fixed position on the casing. Its purpose is to identify the resonant frequency and resonant amplitude of blade vibration. The two-probe method employs two probes located with an appropriate spacing on the casing. Blade displacements measured by two probes under different rotor speed are found. The application of two-parameter method is discussed by comparing with the results of experiment and simulation. Finally, the blade vibration involving rotor speed drifting is studied by simulation. In this simulation, the amplitude and the frequency of disturbance on rotor speed for blade vibration are discussed. Key words: non-contact measurement, light probes, blade tip clearance, blade dynamic mode.
APA, Harvard, Vancouver, ISO, and other styles
6

Marini, Bonnie D. "A combined flow-field/temperature-field study of the impact of blade tip clearance on turbomachinery-type blading /." Diss., 2000. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:9982873.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Tip clearance measurements in turbomachines"

1

Barranger, John P. Low-cost FM oscillator for capacitance type of blade tip clearance measurement system. Cleveland, Ohio: Lewis Research Center, 1987.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Martinez-Sanchez, Manuel. Phase III report on contract number NAS8-35018 entitled Turbine blade tip and seal clearance excitation forces. [Washington, DC]: National Aeronautics and Space Administration, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Martinez-Sanchez, Manuel. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Martinez-Sanchez, Manuel. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

United States. National Aeronautics and Space Administration., ed. Recent advances in capacitance type blade tip clearance measurements. [Washington, D.C.]: National Aeronautics and Space Administration, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

P, Kurkov A., Janetzke David C, and NASA Glenn Research Center, eds. Time-of-flight tip-clearance measurements. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

P, Kurkov A., Janetzke D. C, and NASA Glenn Research Center, eds. Time-of-flight tip-clearance measurements. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

P, Kurkov A., Janetzke David C, and NASA Glenn Research Center, eds. Time-of-flight tip-clearance measurements. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Time-of-flight tip-clearance measurements. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Ramp-integration technique for capacitance-type blade-tip clearance measurement. [Cleveland, Ohio: National Aeronautics and Space Administration, Lewis Research Center, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Tip clearance measurements in turbomachines"

1

Ciocan, Gabriel Dan, and Jean Louis Kueny. "Tip Clearance Flow in Turbomachines — Experimental Flow Analyses." In Hydraulic Machinery and Cavitation, 91–100. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-010-9385-9_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Parrish, C. J. "Dynamic Tip Clearance Measurements in Axial Flow Compressors." In COMADEM 89 International, 419–23. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4684-8905-7_65.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Tip clearance measurements in turbomachines"

1

Janssen, M., J. Seume, and H. Zimmermann. "The Model V84.3 Shop Tests: Tip Clearance Measurements and Evaluation." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-319.

Full text
Abstract:
The design of high-performance gas turbines requires the reliable prediction of blade tip clearances. Excess clearances allow a portion of the hot gas to flow over the blade tips without performing useful work. The tip leakage flow disturbs the flow field which results in additional losses. Moreover, insufficient blade tip clearance may cause interference which can reduce turbine life. In conventional turbomachines, the blade tip clearances vary markedly with the operating condition of the turbine, essentially as a result of variations in gas temperatures and rotor speed. Siemens tests prototype gas turbines in its own test facility. An extensive experimental program is devised to verify design calculations regarding strength, aerodynamics and thermodynamics. Among other measurements, the minimum operating tip clearance is measured by abrasion pins. Electro-mechanical sensors measure transient tip clearance during a selected duty cycle consisting of turning-gear operation, cold start, idle operation, as well as part-load, full-load, and most importantly, hot-start. In the present paper, the compressor and turbine tip clearances measured during such a load cycle are compared with calculated predictions. The experimental instrumentation for the prototype gas turbine, as well as design calculations, are presented. The results show that the new Model V84.3 gas turbine does not exhibit critically small clearances during cold start nor during hot-start due to the careful matching of magnitude and the time constants of the thermal expansion of the blades, discs, blade-ring carriers and casing.
APA, Harvard, Vancouver, ISO, and other styles
2

Lawson, Craig, and Paul Ivey. "Compressor Blade Tip Timing Using Capacitance Tip Clearance Probes." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38284.

Full text
Abstract:
Turbomachinery blade vibrations of sufficient amplitude cause High Cycle Fatigue, which reduces blade life. In order to observe this vibration a non-intrusive monitoring system is sought. The vibration can be detected by measuring blade tip timing since in the presence of vibration the blade timing will differ slightly from the passing time calculated from rotor speed. This paper provides new insights into the ability of a commercially available capacitance probe tip clearance measurement system for application as a non-intrusive turbomachinery blade tip timing measurement device. Initial experimental investigations are reported where a compressor blade with mounted strain gauges is used in a low-speed compressor. Capacitance probe results are correlated with simultaneously measured strain gauge results. Finite Element simulations are also used. The performance of the capacitance system in measuring blade vibration is analysed. Measurements were facilitated by the commissioning of a new instrument dedicated compressor test facility and this test facility is described.
APA, Harvard, Vancouver, ISO, and other styles
3

Stephan, B., H. E. Gallus, and R. Niehuis. "Experimental Investigations of Tip Clearance Flow and its Influence on Secondary Flows in a 1-1/2 Stage Axial Turbine." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0613.

Full text
Abstract:
A multistage turbomachine has inherently unsteady flow fields due to the relative motion between rotor and stator airfoils, which lead to viscous and inviscid interactions between the blade rows. Additionally, the radial clearance between casing and rotor strongly influences the 3D flow field and the loss generation in turbomachines. The objective of the presented study is to investigate the effects of tip clearance on secondary flow phenomena and, in consequence, on the performance of a 1-1/2 stage axial turbine. The low aspect ratio of the blades and their prismatic design leads to a high degree of secondary flows and three-dimensionality. Extended measurements of the flow field behind each blade row with pneumatic and hotwire probes have been conducted for three different tip clearances. Experimental results reveal significant change of flow behavior and turbine performance with increasing tip clearance.
APA, Harvard, Vancouver, ISO, and other styles
4

Sheard, A. G., and S. R. Turner. "Electromechanical Measurement of Turbomachinery Blade Tip-to-Casing Running Clearance." In ASME 1992 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/92-gt-050.

Full text
Abstract:
It is difficult to make a reliable measurement of running clearance in the hostile environment over the blading of modern gas turbines. When the engine manufacturers require the measurement to be made during tests lasting many hours, or even days, measurement system ruggedness and reliability are of primary importance. This paper describes how a second generation tip clearance measurement system of much reduced size and weight was developed. The reduction of size and weight facilitates the use of this measurement system for blade tip-to-casing measurements on all engine development tests from rig to flight worthy engines. During the course of commissioning, the measurement system was tested first in the laboratory, then on progressively more demanding test vehicles. The final test was on the high pressure turbine of a modern military full scale development single spool core. During the course of this test, the mean engine Turbine Entry Temperature through the blading over which clearance was measured, exceeded 1800 K and is typical of the applications for this second generation system.
APA, Harvard, Vancouver, ISO, and other styles
5

Lange, Martin, Matthias Rolfes, Ronald Mailach, and Henner Schrapp. "Periodic Unsteady Tip Clearance Vortex Development in a Low Speed Axial Research Compressor at Different Tip Clearances." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-64256.

Full text
Abstract:
Since the early work on axial compressors the penalties due to radial clearances between blades and side walls are known and an ongoing focus of research work. The periodic unsteadiness of the tip clearance vortex, due to its interaction with the stator wakes, has only rarely been addressed in research papers so far. The current work presents experimental and numerical results from a four stage low speed research compressor modeling a state of the art compressor design. Time-resolved experimental measurements have been carried out at three different rotor tip clearances (gap to tip chord: 1.5%, 2.2%, 3.7%) to cover the third rotor’s casing static pressure and exit flow field. These results are compared with either steady simulations using different turbulence models or harmonic RANS calculations to discuss the periodical unsteady tip clearance vortex development at different clearance heights. The prediction of the local tip leakage flow is clearly improved by the EARSM turbulence model compared to the standard SST model. The harmonic RANS calculations (using the SST model) improve the prediction of time-averaged pressure rise and are used to analyze the rotor stator interaction in detail. The interaction of the rotor tip flow field with the passing stator wakes cause a segmentation of the tip clearance vortex and result in a sinusoidal variation in blockage downstream the rotor row.
APA, Harvard, Vancouver, ISO, and other styles
6

DeShong, Eric T., Shawn Siroka, Reid A. Berdanier, and Karen A. Thole. "Evaluating the Influence of Rotor-Casing Eccentricity on Turbine Efficiency Including Time-Resolved Flow Field Measurements." In ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/gt2021-59112.

Full text
Abstract:
Abstract The clearance that exists between the casing and turbine blade tips is one of the key drivers of efficiency in gas turbine engines. For this reason, engine manufacturers utilize precise manufacturing techniques and may employ clearance control systems to minimize tip clearances to reduce associated losses. Despite these efforts, turbines typically exhibit some nominal casing ovality or rotor-casing eccentricity, and changes to blade tip clearance during operation commonly occur due to thermal and mechanical stresses. The present study investigates non-axisymmetric tip clearance effects by creating a rotor-casing eccentricity in a one-stage axial test turbine operating in a continuous-duration mode at engine relevant conditions with engine representative hardware. A magnetic levitation bearing system was leveraged to move the turbine shaft to vary the rotor-casing eccentricity without test section disassembly. The results of this study indicate that rotor-casing eccentricity does not affect overall turbine efficiency over the range that was tested, but does locally influence efficiency and the rotor exit flow field. Comparisons of flow angle and secondary flow kinetic energy agreed with previous studies and existing analytical methods, respectively. Collectively, these results indicate that tip clearance can be studied locally on an eccentric rotor.
APA, Harvard, Vancouver, ISO, and other styles
7

Stubbs, Jack David, and Muhammad Arslan Shahid. "Blade Tip Clearance Measurement Systems for High Speed Turbomachinery Applications and the Potential for Blade Tip Timing Applications." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15403.

Full text
Abstract:
Abstract As turbomachinery OEMs focus efforts to further increase reliability, power and efficiencies, the running clearance between blade tips and stator continue to be of the utmost importance. This paper investigates the capability of capacitive tip clearance systems to perform individual blade tip clearance measurements on high speed rotors of up to 90,000rpm. A rotor was designed using finite element analysis; unique blade responses have been predicted. The objective of this investigation was to consider two different approaches to the application of blade tip clearance measurements and the system requirements to accurately measure low levels of radial displacement of a target rotating between 1,000rpm and 90,000rpm. The first uses the standard approach with passive probes and the second, a new technique using active probes that have demonstrated bandwidths of 1.2MHz and increased measuring range with a lower level of measurement uncertainty. Both systems’ approaches are compared, and their capabilities are evaluated for high-speed applications. The higher bandwidth capabilities of the latter system, combined with smaller sensor diameters, produces comparable signal rise times to the optical systems used in blade tip timing measurements. The difference in approach offers the potential of contamination resistant sensors for long term blade tip timing applications and measurement probes that do not require cooling systems to withstand higher temperature applications. The use of different probe configurations, in a number of applications, has demonstrated a two-fold improvement in the measurement range whilst producing lower levels of noise and uncertainty when applied to blade targets made from composites, aluminium and nickel-alloy materials. The measurement data presented includes individual blade’s radial displacement, identified shaft axial displacement, effects of resonance in the test system and the identification of the main drivers of measurement uncertainty along with an achievable value. The capacitive measurement systems’ performance for blade tip clearance is analysed and reported. The capability to perform other measurement techniques such as blade tip timing with a dual use measurement probe is also analysed and reported. This is done by correlating measurement results between the capacitive systems with that of a repeat measurement of the same target using an optical BTT system.
APA, Harvard, Vancouver, ISO, and other styles
8

Sridhar, Vikram, Kam Chana, and Michael Pekris. "High temperature eddy current sensor system for turbine blade tip clearance measurements." In European Conference on Turbomachinery Fluid Dynamics and hermodynamics. European Turbomachinery Society, 2017. http://dx.doi.org/10.29008/etc2017-217.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Serena, Alberto, and Lars E. Bakken. "Investigation of the Blade Tip Clearance Effects on Performance and Stability of a Mixed-Flow Pump: High Speed Camera Recordings of the Flow Structures, Local Measurements and Numerical Simulation." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50398.

Full text
Abstract:
The tip leakage flow affects turbomachines performance generating losses and reducing the effective blading; in addition, unsteady phenomena arise, negatively influencing the machine stability. In this paper, an overview of the existing models is presented. Local measurements of the pressure pulsations, visual flow observations and high quality video recordings from a high speed camera are performed in a novel pump laboratory, which provides the desired visualization of the rotating channels, and allows to study the fluctuating and intermittent nature of this phenomenon, and detect any asymmetry among the channels. A detailed comparison of the vortex tip structure for various tip clearances and with a whole set of numerical simulations finally completes the analysis. The three main focus areas are: tip vortex location, structure and evolution, performance comparison between shrouded and open impeller, at different tip clearance sizes, and study of the rotating instabilities.
APA, Harvard, Vancouver, ISO, and other styles
10

Magno, David, Anthony Gannon, Walter Smith, and Garth Hobson. "Analytical Methods for Transonic Compressor Rotor Blade Tip Clearance Measurements Using Capacitive Probes." In ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-82750.

Full text
Abstract:
Abstract A method is presented to improve the capability of proximity sensing capacitive probes used in rotor blade tip clearance (BTC) measurements. This research presents the development and result of a post-processing method used to calibrate capacitive probe instrumentation that will be used to passively analyze BTC of a transonic axial fan under high-speed and high-transient loading. The method attempts to address limitations currently placed on BTC measurements due to poor a SNR. Each revolution’s raw capacitive probe signal is uniformly resampled to a synchronizing once-per-revolution signal, normalizing the data. This reduces timing inaccuracies in the sampling frequency inherent to the data acquisition system and transfers data into a spatial domain removing time dependence and rotational speed variance, which in turn improves the SNR. A Fast Fourier Transform (FFT) is used to identify acceptable lowpass filter passbands that are then adaptively applied to this resampled data based on tip clearance distance. This produces increased precision and dynamic range in capacitive probe calibration compared to existing BTC calibration methods. Use of the proposed method gives the potential ability to operate capacitive probes at larger ranges and in poor SNR environments and gives a possible application in monitoring rotor blade integrity, at a low, additional computation time cost.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Tip clearance measurements in turbomachines' for particular source types:
Journal articles Books
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography