ground vibration testing of airplane pylon-store dynamics using 2010-05-11آ  ground vibration...

Download Ground Vibration Testing of Airplane Pylon-Store Dynamics using 2010-05-11آ  ground vibration testing

Post on 06-Aug-2020

0 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • GROUND VIBRATION TESTING OF AIRPLANE PYLON-STORE DYNAMICS USING LASER DOPPLER VIBROMETER AND ACCELEROMETER

    TECHNIQUES

    By

    JOSEPH DUPUIS

    A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT

    OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE

    UNIVERSITY OF FLORIDA

    2003

  • ACKNOWLEDGMENTS

    I would like express my sincere gratitude to all of my committee members for

    their support on this project. In particular I would like to thank Dr. Richard Lind

    for providing daily guidance throughout the course of the entire project without

    which success would never have been realized. I would like to thank Dr. Andrew

    Kurdila and Roque Salas from SEEK EAGLE for arranging the project and providing

    logistic support. I would also like to thank Dr. Christopher Niezrecki for offering his

    suggestions for improving the quality of the work presented.

    I offer special thanks to the technicians at the STEM facility at Eglin Air Force

    Base for their assistance in implementing the test.

    Finally I would like to thank all my friends, family and coworkers for their

    support in various ways throughout the years.

    ii

  • TABLE OF CONTENTS page

    ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

    LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

    LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

    ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x

    1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

    1.1 Test Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

    2 TEST HARDWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

    2.1 Test Article . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.2 Excitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.3 Accelerometers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.4 Laser Doppler Vibrometer . . . . . . . . . . . . . . . . . . . . . . . . 14 2.5 Data Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.6 Facility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    3 DATA ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    3.1 Modal Analysis Software . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.2 Using Laser and Accelerometer Data Cooperatively: Method 1 . . . . 20 3.3 Using Laser and Accelerometer Data Cooperatively: Method 2 . . . . 25

    4 GVT ON PIDS-3 AND MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . 28

    4.1 Test Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 4.2 Consideration of Excitation Signals . . . . . . . . . . . . . . . . . . . 30 4.3 Accelerometer Response to Vertical Excitation . . . . . . . . . . . . . 32 4.4 Accelerometer Response to Lateral Excitation . . . . . . . . . . . . . . 40 4.5 Laser Response to Lateral Excitation . . . . . . . . . . . . . . . . . . 46 4.6 Scan Response to Lateral Excitation . . . . . . . . . . . . . . . . . . . 50

    5 GVT ON PIDS-3 AND GBU-10 . . . . . . . . . . . . . . . . . . . . . . . . . 55

    5.1 Test Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 5.2 Accelerometer Response to Lateral Excitation . . . . . . . . . . . . . . 56

    iii

  • 6 SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

    REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

    BIOGRAPHICAL SKETCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

    iv

  • LIST OF TABLES Table page

    2–1 Dimensions for the MK-84 and GBU-10 Munitions . . . . . . . . . . . . . 9

    3–1 Effect of FFT Size on Modal Parameters . . . . . . . . . . . . . . . . . . . 24

    4–1 Modes Measured by Accelerometers for Vertical Excitation to MK-84 . . . 33

    4–2 AutoMAC of Accelerometer Response for Vertical Excitation to MK-84 . . 34

    4–3 Modes Measured by Accelerometers for Lateral Excitation to MK-84 . . . 41

    4–4 AutoMAC of Accelerometer Response for Lateral Excitation to MK-84 . . 42

    4–5 Modes Measured by Laser for Lateral Excitation to MK-84 . . . . . . . . . 47

    4–6 AutoMAC of Laser Response for Lateral Excitation to MK-84 . . . . . . . 48

    5–1 Modes Measured for Lateral Excitation to GBU-10 . . . . . . . . . . . . . 57

    5–2 AutoMAC of Accelerometer Response for Lateral Excitation to GBU-10 . 57

    v

  • LIST OF FIGURES Figure page

    2–1 MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

    2–2 GBU-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

    2–3 PIDS-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

    2–4 Excitation System for GVT . . . . . . . . . . . . . . . . . . . . . . . . . . 12

    2–5 PCB Accelerometer Model 352C67 . . . . . . . . . . . . . . . . . . . . . 13

    2–6 Accelerometer Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

    2–7 Polytec Scanning Laser Doppler Vibrometer . . . . . . . . . . . . . . . . . 14

    2–8 IOtech Data Acquisition System . . . . . . . . . . . . . . . . . . . . . . . 15

    2–9 STEM Facility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    3–1 Laser and Accelerometer Frequency Response Functions . . . . . . . . . . 21

    3–2 Beam Second-Bending Mode Shape . . . . . . . . . . . . . . . . . . . . . 22

    3–3 Effect of FFT Size on FRF of Laser Data . . . . . . . . . . . . . . . . . . 22

    3–4 Effect of FFT Size on Curve Fit . . . . . . . . . . . . . . . . . . . . . . . 23

    3–5 Poorly Animated Mode Shape . . . . . . . . . . . . . . . . . . . . . . . . 24

    3–6 Frequency Response Function at Various Locations . . . . . . . . . . . . . 25

    3–7 Separate Subsection FRFs . . . . . . . . . . . . . . . . . . . . . . . . . . 26

    4–1 Excitation Points for GVT of MK-84 . . . . . . . . . . . . . . . . . . . . 28

    4–2 Measurement Points for GVT of MK-84 with Accelerometers . . . . . . . 29

    4–3 Measurement Points for GVT of MK-84 with Accelerometers . . . . . . . 29

    4–4 Measurement Points for GVT of MK-84 with Laser Vibrometer . . . . . . 30

    4–5 Transfer Functions for Random Burst and Sine Sweep Excitation . . . . . 31

    4–6 Transfer Functions for 10 and 35 lb Force Excitation . . . . . . . . . . . . 31

    4–7 Transfer Functions for 1024 and 2048 Point Transforms . . . . . . . . . . 32

    vi

  • 4–8 Transfer Functions at Representative Locations . . . . . . . . . . . . . . . 33

    4–9 Mode Shape at 46 Hz Measured by Accelerometer for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

    4–10 Mode Shape at 183 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

    4–11 Mode Shape at 312 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

    4–12 Mode Shape at 443 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

    4–13 Mode Shape at 507 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

    4–14 Mode Shape at 671 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

    4–15 Mode Shape at 831 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

    4–16 Mode Shape at 899 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

    4–17 Mode Shape at 946 Hz Measured by Accelerometers for Vertical Excita- tion to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

    4–18 Transfer Functions at Representative Locations . . . . . . . . . . . . . . . 40

    4–19 Mode Shape at 186.3 Hz Measured by Accelerometers for Lateral Exci- tation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

    4–20 Mode Shape at 296.9 Hz Measured by Accelerometers for Lateral Exci- tation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

    4–21 Mode Shape at 356.59 Hz Measured by Accelerometers for Lateral Ex- citation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

    4–22 Mode Shape at 548.51 Hz Measured by Accelerometers for Lateral Ex- citation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

    4–23 Mode Shape at 680.64 Hz Measured by Accelerometers for Lateral Ex- citation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

    4–24 Mode Shape at 858.42 Hz Measured by Accelerometers for Lateral Ex- citation to MK-84 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

    vii

  • 4–25 Mode Shape at 969.66 Hz Measured by Accelerometers for Lateral Ex- citati

Recommended

View more >