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Techniques to generate and optimize the load spectra for an aircraft

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Abstract

In this article, described the various techniques to generate the load spectra for an aircraft and optimize the generated loading sequence. The generation of loading sequence is carried out from the Flight Data Recorder (FDR), which records various parameters in flight. In this article main focus is on ‘g’ accelerations as these are used for load spectra generation. This article describes the techniques viz., (i) Peak-trough counting, (ii) Level cross counting algorithms to count the number of exceedances. After implementing and using these techniques, listed the advantages and disadvantages of these techniques. For a successful usage of generated load sequence for a test/analysis, it is necessary to optimize the generated loading sequence or turning points. The optimization of generated load sequence is carried out by filtering small cycle amplitudes of load/‘g’ ranges. At different range levels the filtering has been carried out, to arrive at an optimum range level of filtering. In order to be certain that the optimized spectra has not lost its severity and shape it has been re-plotted with the original spectra on the same graph. This optimization exercise useful in reducing the testing time.

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References

  • Amzallag, C., Gerey, J.P., Robert, J.L., Bahuaudt, J.: Standardization of the rainflow counting method for fatigue analysis. Int. J. Fatigue 16, 287–293 (1994)

    Article  Google Scholar 

  • Anthes, R.J.: Modified rainflow counting keeping the load sequence. Int. J. Fatigue 19(7), 529–535 (1997)

    Article  Google Scholar 

  • ASTM Standard E1049: Standard Practices for Cycle Counting in Fatigue Analysis, vol. 5. ASTM Standard E1049, Philadelphia, PA (2005)

  • Berens, A.P.: Determination of sample size in flight loads program, service fatigue loads monitoring, simulation and analysis. ASTM STP 671, 36–48 (1979)

    Google Scholar 

  • Broek, D.: The Practical Use of Fracture Mechanics, Textbook. Kluwer Academic Publishers, USA (1988)

    Google Scholar 

  • De Jonge, J.B.: The Analysis of Load-Time Histories by Means of Counting Methods, NLR MP 82039 U. National Aerospace Laboratories, The Netherlands (1982)

    Google Scholar 

  • De Jonge, J.B.: Additional Information about FALSTAFF, National Aerospace Laboratory, NLR TR 79056 U, 12 June (1979)

  • Denyer, A.G.: Flight-by-flight spectrum development, service fatigue loads monitoring, simulation and analysis. ASTM STP 671, 158–175 (1979)

    Google Scholar 

  • Downing, S.D., Socie, D.F.: Simple rainflow algorithm. Int. J. Fatigue 4(1), 31–40 (1982)

    Article  Google Scholar 

  • Ghoshal, S., Sunder, R.: Parametric Analysis of Fatigue under Random Loading, PD ST 8933. NAL, Bangalore (1989)

    Google Scholar 

  • Glinka, G., Kam, J.C.P.: Rainflow counting algorithm for very long stress histories. Int. J. Fatigue 9(4), 223–228 (1987)

    Article  Google Scholar 

  • Heuler, P., Klatschke, H.: Generation and use of standardized load spectra and load time histories. Int. J. Fatigue 27, 974–990 (2005)

    Article  MATH  Google Scholar 

  • Hong, N.: A modified rainflow counting method. Int. J. Fatigue 13(6), 465–469 (1991)

    Article  Google Scholar 

  • Johannesson, P.: Extraction of load histories and spectra. Fatigue Fract. Eng. Mater. Struct. 29, 201–207 (2006)

    Article  Google Scholar 

  • Kaplan, M.P., Reiman, A., Landy, M.A., et al.: Derivation of flight-by-flight spectra for fighter aircraft, service fatigue loads monitoring, simulation and analysis. ASTM STP 671, 193–207 (1979)

    Google Scholar 

  • Lee Y.-L., Pan, J.: Fatigue Testing and Analysis, Theory and Practice, Elsevier Publication. ISBN: 0-7506-7719-8 (2004)

  • McInnes, C.H., Meehan, P.A.: Equivalence of four-point and three-point rainflow cycle counting algorithm. Int. J. Fatigue 30(3), 547–559 (2008)

    Article  Google Scholar 

  • Military Specification, Airplane Strength and Rigidity Reliability Requirements, Repeated Loads and Fatigue, MIL-A-008866B, 22 August (1975)

  • Molent, L., Aktepe, B.: Review of fatigue monitoring of agile military aircraft, Blackwell Science Ltd. Fatigue Fract. Eng. Mater. Struct. 23, 767–785 (2000)

    Article  Google Scholar 

  • Olagnon, M.: Practical Computation of Statistical properties of rainflow counts. Int. J. Fatigue 16(5), 306–314 (1994)

    Article  Google Scholar 

  • Raju, K.N., Lakshminarayana, H.V., Dattaguru, B.: Workshop on ‘Fracture, Fatigue and Failure Analysis’, Part: III, Fatigue, Organised by National Aerospace Laboratories, Bangalore, February 26–March 10 (1979)

  • Schijve, J.: Fatigue of Structures and Materials, Textbook. Kluwer Academic Publishers (Springer Verlag), Dordrecht, The Netherlands (2001)

    Google Scholar 

  • Schijve, J.: Fatigue damage in aircraft structures, not wanted, but tolerated? Int. J. Fatigue 31, 998–1011 (2009)

    Article  MATH  Google Scholar 

  • Schutz, W.: Fatigue life prediction: Calculation or Experiment? Life Assessment of Dynamically loaded Materials and Structures, ECF-5, September 17–21 (1984)

  • Van Dijk G.M., de Jonge J.B.: Introduction to a fighter aircraft loading standard for fatigue evaluation, NLR MP 75017 U, 20 May (1975)

  • van Gelder, P.: GENESIS 4 Fatigue, National Aerospace Laboratory NLR, the Netherlands. Developed as part of the NLR LOADPROC project. (2001)

  • WAFO: A Matlab Toolbox for Wave Analysis for Fatigue and Oceanography, Random Waves and Loads, The WAFO group, Lund University, Lund Institute of Technology, Centre for Mathematical Sciences, Mathematical Statistics, August (2000)

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Acknowledgments

The authors gratefully acknowledge the 11-BRD for sponsoring the project to National Aerospace Laboratories (NAL). The authors also thank the Director, NAL, Dr. A. R. Upadhya for his valuable support towards this activity.

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  1. Structural Technologies Division, National Aerospace Laboratories, Bangalore, 560017, India

    Krishna Lok Singh & D. V. Venkatasubramanyam

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  1. Krishna Lok Singh
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  2. D. V. Venkatasubramanyam
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Correspondence to Krishna Lok Singh.

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Singh, K.L., Venkatasubramanyam, D.V. Techniques to generate and optimize the load spectra for an aircraft. Int J Mech Mater Des 6, 63–72 (2010). https://doi.org/10.1007/s10999-010-9121-7

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  • DOI: https://doi.org/10.1007/s10999-010-9121-7

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