پیوندهای مفید
آمار
| تعداد نشریات | 8 |
| تعداد شماره‌ها | 419 |
| تعداد مقالات | 5,514 |
| تعداد مشاهده مقاله | 6,249,040 |
| تعداد دریافت فایل اصل مقاله | 5,419,472 |
بررسی نیمه تحلیلی نویز لبه فرار لایه مرزی آشفته با استفاده از اندازه گیری فشار ناپایای سطح | ||
| نشریه مهندسی مکانیک امیرکبیر | ||
| مقاله 6، دوره 51، شماره 6، بهمن و اسفند 1398، صفحه 1253-1270 اصل مقاله (1.27 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/mej.2017.12480.5352 | ||
| نویسندگان | ||
| عباس افشاری1؛ علی اکبر دهقان* 2؛ محمد فرمانی3 | ||
| 1دانشجوی دکترا/ دانشگاه یزد | ||
| 2هیلت علمی-دانشگاه یزد | ||
| 3دانشجوی دکتری/ دانشگاه یزد | ||
| چکیده | ||
| نویز لبه فرار لایه مرزی آشفته یکی از منابع اصلی نویز آیرودینامیکی بوده و در دهه های گذشته مطالعات گستردهای روی آن انجام گرفته است. در مطالعه حاضر جهت اندازه‌گیری پارامترهای تعیین کننده نویز لبه فرار شامل طیف فشار سطح، طول مشخصه نوسانات فشار سطح در راستای دهانه بال و سرعت جابجایی ساختارهای گردابه ای در محدوده لبه فرار، از یک صفحه تخت مجهز به حسگرهای فشار سطحی در دو راستای جریان و دهانه بال استفاده شده است. طول مشخصه در راستای دهانه مدل و سرعت جابجایی ساختارهای گردابه-ای، به ترتیب از طریق داده‌برداری همزمان فشار ناپایای سطح در نقاط مختلف در راستای دهانه مدل و در راستای جریان محاسبه شده است. نتایج نشان می‌دهد که بهترین اجتماع داده‌های طیف فشار سطح در محدوده بسامدهای پایین و بسامدهای میانی و بالا به ترتیب به ازای استفاده از مقیاس-های الیه مرزی خارجی و داخلی حاصل خواهد شد. همچنین توابع همدوسی طولی و عرضی، به ترتیب اطلاعات مناسبی از طول عمر ساختارهای گردابه ای و ابعاد فیزیکی آنها ارائه می‌دهد. در نهایت، نویز لبه فرار دوردست ناشی از جریان عبوری از روی صفحه تخت با استفاده از مدل تحلیلی امیت-راجر پیش بینی شده که نتایج نشان دهنده کارایی مناسب این مدل در پیش‌بینی نویز لبه فرار لایه مرزی آشفته است. | ||
| کلیدواژه‌ها | ||
| نویز لبه فرار؛ لایه مرزی آشفته؛ طیف فشار سطح؛ سرعت جابه جایی ساختارهای گردابه ای؛ طول مشخصه در راستای دهانه | ||
| عنوان مقاله [English] | ||
| Semi-empirical Investigation of Trailing Edge Noise by Measuring Unsteady Surface Pressures | ||
| نویسندگان [English] | ||
| abbas afshari1؛ Ali Akbar Dehghan2؛ mohammad farmani3 | ||
| 1phd student / yazd university | ||
| 3phd student/ yazd university | ||
| چکیده [English] | ||
| Turbulent boundary layer trailing edge noise is one of the main sources of aerodynamic noise and extensive studies have been devoted to trailing edge noise identification during the past decades. In the present study, for measuring the main parameters affecting the trailing edge noise including the surface pressure spectra, the spanwise length scale of the surface pressure fluctuations and eddy convection velocity in the trailing edge region, a flat-plate model equipped with several streamwise and spanwise surface pressure transducers is designed and built. The spanwise length scale and eddy convection velocity are calculated by simultaneously measuring of unsteady surface pressure in both streamwise and spanwise directions. The results show that the best collapses in the surface pressure spectra at low frequency and mid to high frequencies can be obtained by using outer and inner layer scales respectively. Furthermore, the longitudinal and lateral coherences can provide adequate information about the lifespan of the turbulent eddies and their physical size. Finally, the far-field trailing edge noise induced by the turbulent flow over the flat plate has been predicted by using the Amit-Roger model and results show the effectiveness of this model for prediction of far-field turbulent boundary layer trailing edge noise. | ||
| کلیدواژه‌ها [English] | ||
| Trailing edge noise, Turbulent boundary layer, Surface pressure spectra, Eddy convection velocity, Spanwise length scale | ||
|
سایر فایل های مرتبط با مقاله
|
||
| مراجع | ||
|
[1] R. Royce, The jet engine, 5th Edition ed., John Wiley & Sons, 2015. [2] N.E. Antoine, I.M. Kroo, Aircraft optimization for minimal environmental impact, Journal of aircraft, 41(4) (2004) 790-797. [3] M. Roger, S. Moreau, Trailing edge noise measurements and prediction for subsonic loaded fan blades, AIAA paper, 2460 (2002). [4] W.K. Blake, Mechanics of flow-induced sound and vibration V2: complex flow-structure interactions, 2nd edn ed., Academic Press., 2017. [5] D.P. Lockhard, G.M. Lilley, The airframe noise reduction challenge, Tech. Rep. NASA/TM-2004213013, NASA Langley Research Center, (2004). [6] S. Oerlemans, M. Fisher, T. Maeder, K. Kögler, Reduction of wind turbine noise using optimized airfoils and trailing-edge serrations, AIAA Journal, 47(6) (2009) 1470-1481. [7] T.F. Brooks, D.S. Pope, M.A. Marcolini, Airfoil selfnoise and prediction, National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, 1989. [8] A. Powell, On the aerodynamic noise of a rigid flat plate moving at zero incidence, The Journal of the Acoustical Society of America, 31(12) (1959) 1649-1653. [9] T.F. Brooks, T. Hodgson, Trailing edge noise prediction from measured surface pressures, Journal of sound and vibration, 78(1) (1981) 69-117. [10] M. Wang, P. Moin, Computation of trailing-edge flow and noise using large-eddy simulation, AIAA journal, 38(12) (2000) 2201-2209. [11] A3 Garcia-Sagrado, T. Hynes, Wall pressure sources near an airfoil trailing edge under turbulent boundary layers, Journal of Fluids and Structures, 30 (2012) 3-34. [12] Herrig, M. Kamruzzaman, W. Würz, S. Wagner, Broadband airfoil trailing-edge noise prediction from measured surface pressures and spanwise length scales, noise notes, 12(4) (2013) 13-36. [13] M.J. Lighthill, On sound generated aerodynamically. I. General theory, in: Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences, The Royal Society, 1952, pp. 564-587. [14] J.F. Williams, L. Hall, Aerodynamic sound generation by turbulent flow in the vicinity of a scattering half plane, Journal of Fluid Mechanics, 40(04) (1970) 657-670. [15] D.M. Chase, Noise radiated from an edge in turbulent flow, AIAA journal, 13(8) (1975) 10411047. [16] R. Amiet, Noise due to turbulent flow past a trailing edge, Journal of Sound and Vibration, 47(3) (1976) 387-393. [17] M. Howe, A review of the theory of trailing edge noise, Journal of Sound and Vibration, 61(3) (1978) 437-465. [18] M. Roger, S. Moreau, M. Wang, An analytical model for predicting airfoil self-noise using wallpressure statistics, Annual Research Brief, Center for Turbulence Research, Stanford University, (2002) .414-504 [19] M. Mosallem, Numerical and experimental investigation of beveled trailing edge flow fields, Journal of Hydrodynamics, Ser. B, 20(3) (2008) 273.279. [20] J.B. Barlow, W. Rae, A. Pope, Low-speed wind tunnel testing, John Wiely & Sons, in, Wiley, New York, 1999. [21] S. Moreau, P. Laffay, A. Idier, N. Atalla, Several noise control of the trailing-edge noise of a ControlledDiffusion airfoil, in: 22nd AIAA/CEAS Aeroacoustics Conference, 2016, pp. 2816. [22] A. Afshari, A. A. Dehghan, V. Kalantar, M. Farmani, Experimental investigation of surface pressure spectra beneath turbulent boundary layer over a flat plate with microphone, Modares Mechanical Engineering, 17(1) (2017) 263-272. (in Persian) [23] Afshari, A. A. Dehghan, V. Kalantar, M. Farmani, Analytical and Experimental investigation of remote microphone system response for prediction of surface pressure fluctuations, Modares Mechanical Engineering, 16(10) (2016) 155-162. (in Persian) [24] G. Corcos, Resolution of pressure in turbulence, The Journal of the Acoustical Society of America, 35(2) (1963) 192-199. [25] G. Schewe, On the structure and resolution of wall-pressure fluctuations associated with turbulent boundary-layer flow, Journal of Fluid Mechanics, 134 (1983) 311-328. [26] S. Gravante, A. Naguib, C. Wark, H. Nagib, Characterization of the pressure fluctuations under a fully developed turbulent boundary layer, AIAA journal, 36(10) (1998) 1808-1816. [27] M. Goody, Empirical Spectral Model of Surface Pressure Fluctuations, AIAA Journal, 42(9) (2004) 1788-1794. [28] M. Bull, A. Thomas, High frequency wallpressure fluctuations in turbulent boundary layers, Physics of Fluids (1958-1988), 19(4) (1976) 597-599. [29] M. Bull, Wall-pressure fluctuations beneath turbulent boundary layers: some reflections on forty years of research, Journal of Sound and Vibration, 190(3) (1996) 299-315. [30] M. Goody, R.L. Simpson, An experimental investigation of pressure fluctuations in threedimensional turbulent boundary layers, DTIC Document, 1999. [31] É. Salze, C. Bailly, O. Marsden, E. Jondeau, D. Juvé, An experimental characterization of wall pressure wavevector-frequency spectra in the presence of pressure gradients, in: 20th AIAA/CEAS Aeroacoustics Conference, AIAA Paper, 2014, pp. 2014. [32] Q. Leclère, A. Pereira, A. Finez, P. Souchotte, Indirect calibration of a large microphone array for in-duct acoustic measurements, Journal of Sound and Vibration, 376 (2016) 48-59. [33] F.J. Fahy, P. Gardonio, Sound and structural vibration: radiation, transmission and response, Academic press, 2007. [34] D. Spalding, A single formula for the “law of the wall”, Journal of Applied Mechanics, 28(3) (1961) 455-458. [35] F. White, Viscous fluid flow: 614, in, McGrawHill Book Company, New York, 1991. [36] J.S. Bendat, A.G. Piersol, Random data: analysis and measurement procedures, John Wiley & Sons, 2011. [37] G. Corcos, The structure of the turbulent pressure field in boundary-layer flows, Journal of Fluid Mechanics, 18(03) (1964) 353-378. [38] E. Finn, Jørgensen, How to measure turbulence with hot-wire anemometers‖, Publication no.: 9040U6151, Date 2002-02-01. Dantec Dynamics A/S, PO Box 121, Tonsbakken 16-18, DK-2740 …, 2002. [39] S. Yavuzkurt, A guide to uncertainty analysis of hot-wire data, ASME, Transactions, Journal of Fluids Engineering, 106 (1984) 181-186. [40] Y.F. Hwang, W.K. Bonness, S.A. Hambric, Comparison of semi-empirical models for turbulent boundary layer wall pressure spectra, Journal of Sound and Vibration, 319(1-2) (2009) 199-217. [41] W.L. Keith, D. Hurdis, B. Abraham, A comparison of turbulent boundary layer wall-pressure spectra, Journal of Fluids Engineering, 114(3) (1992) 338-347. [42] N. Hu, M. Herr, Characteristics of wall pressure fluctuations for a flat plate turbulent boundary layer with pressure gradients, in: 22nd AIAA/CEAS Aeroacoustics Conference, 2016, pp. 2749. [43] M. Bull, Wall-pressure fluctuations associated with subsonic turbulent boundary layer flow, Journal of Fluid Mechanics, 28(04) (1967) 719-754. [44] D.J. Moreau, L. Brooks, C.J. Doolan, Experimental investigation of broadband trailing edge noise from sharp-edged struts, in: 17th AIAA/CEAS Aeroacoustics Conference Portland, Oregon, 2011. | ||
|
آمار تعداد مشاهده مقاله: 963 تعداد دریافت فایل اصل مقاله: 732 |
||
