بررسی تجربی اثر پیش‌بار و چیدمان پیچ بر عملکرد اتصالات کامپوزیتی پوسته ناسل توربین بادی مگاواتی

نوع مقاله : مقاله پژوهشی

نویسندگان

پژوهشگاه نیرو، گروه انرژی‌های تجدیدپذیر، تهران، ایران

چکیده

پوسته ناسل و دماغه اغلب توربین‌های بادی مگاواتی از جنس ورق های کامپوزیتی می‌باشد. با توجه به شکل و هندسه‌های مختلف و همچنین ابعاد بزرگ این قطعه، امکان ساخت یکپارچه پوسته ناسل توربین بادی وجود ندارد. از اینرو، این قطعات از تکه‌های متعددی تشکیل شده است که بنا به نیاز مکرر توربین بادی به تعمیر و نگهداری در طول عمر بیست ساله خود، این قطعات باید توسط اتصالات غیر دائم مکانیکی همچون پیچ و مهره به یکدیگر متصل شوند. از اینرو با توجه به اهمیت موضوع، شناختن تمام پارامترهای اثر گذار و موثر بر اتصالات کامپوزیتی از اهمیت بسزایی برخوردار است. یکی از مهم‌ترین پارامترهای طراحی اتصالات پیچی، میزان پیش بار پیچ و انتخاب شماره پیچ می‌باشد. با توجه به جنس ورق‌های دو طرف اتصال در پوسته ناسل، امکان افزایش بی‌مهابای پیش بار وجود ندارد. چرا که خود این موضوع می‌تواند منجر به آسیب‌هایی به ورق‌‌های کامپوزیتی گردد. از اینرو در این مقاله، در ابتدا تاثیر پیش بار پیچ و یا گشتاور سفت کردن پیچ در اتصالات کامپوزیتی، به روش تجربی مورد ارزیابی قرار گرفته است. برای این منظور نمونه‌های یکسانی با گشتاورهای سفت کنندگی پیچ 2، 10، 20، 30، 40 و 50 نیوتن بر متر ساخته و تحت آزمون کشش قرار گرفته است. در ادامه، پس از تعیین بهینه‌ترین نیروی پیش بار، برای یافتن بهترین حالت چیدمان پیچ‌ها، 4 نوع چیدمان مختلف نیز مورد آزمون تجربی قرار گرفت. و درنهایت با بررسی جوانب مختلف، بهترین چیدمان برای اتصال بخش‌های مختلف پوسته ناسل و دماغه در بارهای کششی که بار غالب در پوسته ناسل طراحی شده می‌باشد، تعیین گردید.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental Study of Preload and Bolt Arrangement on Composite Joint Performance in Megawatt Wind Turbine's Nacelle Cover and Nose Cone

نویسندگان [English]

  • Aidin Ghaznavi
  • S. Abolfazl Mousaavi
Renewable Energy Research Department, Niroo Research Institute (NRI), Tehran, Iran
چکیده [English]

The nacelle cover and nose cones of most megawatt wind turbines are made of composite sheets. Due to the complex shapes, geometries, and large dimensions of these components, they are composed of several parts that must be assembled using non-permanent mechanical joints, such as bolts. Therefore, it is very important to consider all the effective parameters that affect composite joints. One of the most critical design parameters for bolt connections is the amount of bolt preload or tightening torque. However, increasing the preload without caution is not feasible due to the composite material present on both sides of the joint, as this can potentially damage the composite sheets. As a result, this paper aims to evaluate experimentally the effect of bolt preload or tightening torque on composite joints. To achieve this, identical specimens were fabricated, each with a different bolt tightening torque ranging from 2 Nm to 50 Nm. These specimens were then subjected to a tensile load. After determining the optimal preload force, four different types of arrangements were experimentally tested to find the best bolt arrangement. Finally, by examining various aspects, the best arrangement for connecting different parts of the nacelle cover and nose cone was determined.

کلیدواژه‌ها [English]

  • Composite joints
  • preload
  • bolt arrangement
  • wind turbine
  • nacelle cover

مراجع

[1] A. Qazi, C. Bhowmik, F. Hussain, S. Yang, U. Naseem, A.-A. Adebayo, A. Gumaei, M. Al-Rakhami, Analyzing the public opinion as a guide for renewable-energy status in Malaysia: A case study, IEEE Transactions on Engineering Management, 99 (2021) 1-15.
[2] N. Kilinc-Ata, The evaluation of renewable energy policies across EU countries and US states: An econometric approach, Energy for Sustainable Development, 31 (2016) 83-90.
[3] C. Harvey, N. Heikkinen, Congress Says Biomass Is Carbon-Neutral, but Scientists Disagree, Scientific American E&E News Environment, USA, (23 March 2018) Archived from the original on 1 November 2020. Retrieved 31 October 2020.
[4] S.A. Moussavi, A. Ghaznavi, Effect of boundary layer suction on performance of a 2 MW wind turbine, Energy, 232 (2021) 121072.
[5] G.M. Pearce, A.F. Johnson, R.S. Thomson, D.W. Kelly, Experimental investigation of dynamically loaded bolted joints in carbon fibre composite structures, Applied Composite Materials, 17 (2010) 271-291.
[6] J. Ekh, Multi-fastener single-lap joints in composite structures, PhD diss., KTH, 2006.
[7] M.B. Tate, Preliminary investigation of the loads carried by individual bolts in bolted joints, 1946.
[8] W. Barrois, Stresses and displacements due to load transfer by fasteners in structural assemblies, Engineering fracture mechanics, 10(1) (1978) 115-176.
[9] W.D. Nelson, B.L. Bunin, L.J. Hart-Smith, Critical joints in large composite aircraft structure, Nasa, 1983.
[10] M. McCarthy, C. McCarthy, G. Padhi, A simple method for determining the effects of bolt–hole clearance on load distribution in single-column multi-bolt composite joints, Composite Structures, 73(1) (2006) 78-87.
[11] M. McCarthy, V. Lawlor, W. Stanley, C. McCarthy, Bolt-hole clearance effects and strength criteria in single-bolt, single-lap, composite bolted joints, Composites science and technology, 62(10-11) (2002) 1415-1431.
[12] V.P. Lawlor, M.A. Mccarthy, W. Stanley, An experimental study of bolt–hole clearance effects in double-lap, multi-bolt composite joints, Composite structures, 71(2) (2005) 176-190.
[13] G. Padhi, M. McCarthy, C. McCarthy, BOLJAT: a tool for designing composite bolted joints using three-dimensional finite element analysis, Composites Part A: Applied Science and Manufacturing, 33(11) (2002) 1573-1584.
[14] P.P. Camanho, F. Matthews, A progressive damage model for mechanically fastened joints in composite laminates, Journal of composite materials, 33(24) (1999) 2248-2280.
[15] K.B. Katnam, L. Da Silva, T. Young, Bonded repair of composite aircraft structures: A review of scientific challenges and opportunities, Progress in Aerospace Sciences, 61 (2013) 26-42.
[16] J. Ekh, J. Schön, Effect of secondary bending on strength prediction of composite, single shear lap joints, Composites science and technology, 65(6) (2005) 953-965.
[17] J. Ekh, J. Schön, Load transfer in multirow, single shear, composite-to-aluminium lap joints, Composites Science and Technology, 66(7-8) (2006) 875-885.
[18] M. McCarthy, C.T. McCarthy, V.P. Lawlor, W.F. Stanley, Three-dimensional finite element analysis of single-bolt, single-lap composite bolted joints: part I—model development and validation, Composite structures, 71(2) (2005) 140-158.
[19] C.T. McCarthy, M.A. McCarthy, V. Lawlor, Progressive damage analysis of multi-bolt composite joints with variable bolt–hole clearances, Composites Part B: Engineering, 36(4) (2005) 290-305.
[20] C. Stocchi, P. Robinson, S. Pinho, A detailed finite element investigation of composite bolted joints with countersunk fasteners, Composites Part A: applied science and manufacturing, 52 (2013) 143-150.
[21] G. Pearce, A. Johnson, A. Hellier, R. Thomson, A study of dynamic pull-through failure of composite bolted joints using the stacked-shell finite element approach, Composite Structures, 118 (2014) 86-93.
[22] J. Hassan, R.M. O'Higgins, T. Feser, M. Waimer, C.T. McCarthy, N. Toso, M.A. McCarthy, Influence of layup, stacking sequence and loading rate on energy absorption of tension-absorber joints, Composite Structures, 261 (2021) 113327.
[23] V.G. Belardi, P. Fanelli, F. Vivio, A novel composite bolted joint element: Application to a single-bolted joint, Procedia Structural Integrity, 12 (2018) 281-295.
[24] E.S. Greenhalgh, C. Canturri, T.J. Katafiasz, Fractographic study into the effect of drilling damage on bearing mechanisms and performance in Carbon-Fibre epoxy composites, Engineering Failure Analysis, 129 (2021) 105638.
[25] J. Wang, T. Qin, N.R. Mekala, Y. Li, M. Heidari-Rarani, K.-U. Schröder, Three-dimensional progressive damage and failure analysis of double-lap composite bolted joints under quasi-static tensile loading, Composite Structures, 285 (2022) 115227.
[26] J.-I. Choi, S.M. Hasheminia, H.-J. Chun, J.-C. Park, H.S. Chang, Failure load prediction of composite bolted joint with clamping force, Composite Structures, 189 (2018) 247-255.
[27] A. VanderKlok, A. Dutta, S.A. Tekalur, Metal to composite bolted joint behavior evaluated at impact rates of loading, Composite Structures, 106 (2013) 446-452.
[28] A. Ghaznavi, M. Asgari, A. Saeidi, M. Ramyar, A. Bahri, H. Lari, Finite element modeling of debonding behavior of adhesively-bonded joints between sandwich panel and pultruded profile in flexural loading, Journal of Solid and Fluid Mechanics, 6 (2016) 107-116 (in Persian).
[29] ISO 286-1:2010 (en), Geometrical product specifications (GPS) - ISO code system for tolerances on linear sizes- Part 1: Basis of tolerances, deviations and fits, Chapter 6 (2010).
[30] ASTM Standard D 5961/D 5961 M-96. Standard test method for bearing response of polymer matrix composite laminates; (2007).
[31] B. Egan, C.T. McCarthy, M. McCarthy, R. Frizzell, Stress analysis of single-bolt, single-lap, countersunk composite joints with variable bolt hole clearance, Composite Structures, 94(3) (2012) 1038-1051.
[32] J.E. Shigley, C.R. Mischke, T.H. Brown Jr, Standard handbook of machine design, McGraw-Hill Education, 2004.
[33] M. Fonte, L. Reis, V. Infante, M. Freitas, Failure analysis of cylinder head studs of a four stroke marine diesel engine, Engineering Failure Analysis, 101 (2019) 298-308.
[34] W.D. Pilkey, D.F. Pilkey, Z. Bi, Peterson's stress concentration factors, John Wiley & Sons, 2020.
نشریه مهندسی مکانیک امیرکبیر
دوره 55، شماره 7
مهر 1402
صفحه 837-856

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