Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK

Transcription

1 Fakultät Maschinenwesen Professur für Dynamik und Mechanismentechnik Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK Dipl.-Ing. Johannes Woller Prof. Dr.-Ing. Michael Beitelschmidt Braunschweig,

2 Project presentation Cooperation between the TU Dresden and Bombardier Transportation GmbH Bombardier Center of Competence Railway Vehicle Engineering Integration Center (since 2007) Subsequent results are part of the research project: Topic: Project head: Employee responsible: Seamless integration of standardized Noise Vibration- Harshness (NVH) calculations in the development process of railway vehicle powertrains Prof. Dr.-Ing. Michael Beitelschmidt Dipl.-Ing. Johannes Woller Duration of the project: 4 years starting 2014 Integration of measured receptance into a time domain 2

3 Structure of the presentation Motivation New Approach Test models Final assembly based on measured data Conclusion Integration of measured receptance into a time domain 3

4 Motivation Airborne noise Interior noise Objective: Calculation of the interior noise of the rail vehicle caused by structure-borne noise from the drive train Unbalance, etc. Excitation of the railwheel contact Excitation of the electrical pulse pattern supply Gearing excitation Transfer of structure-borne noise through the bogie Integration of measured receptance into a time domain 4

5 Motivation Calculation of the structure-borne sound power transmitted to the car body (frequency domain): In Situ: Direct calculation of the coupled variables (with car body model) Structure-borne sound power: In Situ: Integration of measured receptance into a time domain 5

6 Motivation Structure borne sound: Forces and velocities must be calculated for all coupling points between the running gear and the car body Transfer characteristics of the car body is only considered via elastic body for comfort calculation (0-30 Hz) The current model approach is not valid in the higher frequency range FE modeling in this frequency range is not feasible Integration of measured receptance into a time domain 6

7 Structure of the presentation Motivation New Approach Test models Final assembly based on measured data Conclusion Integration of measured receptance into a time domain 7

8 Idea of using black box model Reduced Elastic car body Replaced by Black Box model based on measured data Coupling elements Model border Running Gear Integration of measured receptance into a time domain 8

9 General Approach: Black Box modeling in the acoustical frequency range Measurement System Identification Up to 2000 Hz Transform Simulation Black Box State Space Representation Integration of measured receptance into a time domain 9

10 Idea: Black-Box Sub model Use of force elements including Possible Approaches Co-Simulation (SIMPACK - Simulink) Using SIMPACK Force Elements Using FMU-Import in Simpack of Simulinkmodels Elastic body base on the floating frame of reference formulation transfer functions or state space representations 102,103 Force/Torque by Freq-Resp Transfer Function 1 :By Polynomial Quotient (max. 9 DGF) 141,142 State Space Filter 110, 123 Actuator Force Element Use of specialized force elements Dynamic Bushing/Hydromount Cmp 80 Air Spring Advanced 82 Non-linear Airspring 81 FlexiCoil-Springs 79 Shear Spring Implementation of a user element with dynamic transmission behavior Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 10

11 Structure of the presentation Motivation New Approach Test models Final assembly based on measured data Conclusion Integration of measured receptance into a time domain 11

12 Proof of concept: Minimal models g Higher DOF m c b Simpack q Minimal MIMO-Model SIMPACK g m m c b q c b q m m c b q c q b m q c b Black Box Model Black Box Model c c m m q b q b Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 12

13 Test Model constrained MDof estimated, without gravity Parameter Value m 100 kg Approximation as MDoF - Oscillator! " R % R % c N m m b 1000 Ns m Reference model n 15 c n b q Sub model n8 m q R % c b m q c b Longitudinal vibrations in a rod (no bending) Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 13

14 Estimation of a State Space Model Receptance Matlab System Identification Toolbox Tfest command (Matlab 2016b) (using 16 poles, 14 zeros) Driving Point Receptance at q 8 Reference Estimated transfer function model receptance Tolerance: 0.01 Iterations: 1 (max. 50) Initialization Method: n4sid (modal subspace) Result: Number of poles: 16 Number of zeros: 14 Number of free coefficients: 31 Fit to estimation data: 100% Amplitude Frequency in Hz Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 14

15 Receptance / Mobility Coupling Force Element Joint with Degree of Freedom Black Box Model SSM-File 5 m * 1(z) Sensor Control Element Marker uf & q & q' 5 m m + 1(z) Subvariable Excitation Constraint 85 1(z) Integration of measured receptance into a time domain 15

16 Receptance sub model: Frequency response function Dynamic behavior, Initial: non equilibrium state Frequency domain (Laplace Transformation) Time domain (numerical integration) F jω,f(ωt) Mobility: Response Respose From Black Reference Time Box Domain BlackBox Model Mobility: Respose Response From Black Reference Time Box Domain Reference Model Mobility: x 10x -3 From 10-6 Frequency Domain BlackBox Model Mobility: From Frequency Domain Reference Model Response Mobility Time Domain Diagram 4, q, (jω),q, (t) m/ns z [m/s] Time Domain Excitation: Sine-Sweep Hz in 500 s (0.6 Hz/s) Frequency time time in [s] Hz[s] Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 16

17 Structure of the presentation Motivation New Approach Test models Final assembly based on measured data Conclusion Integration of measured receptance into a time domain 17

18 Validation: Experimental test model Experimental-Analytical Dynamic Substructuring for Multi Body Simulation A.T. Moorhouse A.S. Elliott Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 18

19 Reference model Source beam (running gear) X A B Y Timoshenko Beam models Tunable Coupling Stiffness Receiver beam (car body) Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 19

20 FRF Measurement 4x4 FRF Measurement at Receiver Beam Excitation Impulse Hammer PCP 086C80 0,44g Response Polytec Laser Scanning Vibrometer PSV500 Suspension Resilient Mounting (rubber components) highest mounting frequency 23 Hz Lowest eigenfrequency 150 Hz Signal Processing Sampling Frequency: /s FFT: 3200 FFT Lines Window Function: Force/Exponential Average: 3;complex Estimated Transfer function H1 Integration of measured receptance into a time domain 20

21 Insight model and measurement Receiver Receptance; db Reference= 10-6 m/n 100 From: In(1) To: q A x Magnitude (db) A B Phase (deg) Timoschenko-Model Measured Receptance f_a x to q_a x Frequency (Hz) Integration of measured receptance into a time domain 21

22 System Identification Matlab System Identification Toolbox n4sid command (Matlab 2016b) (modal subspace method) Initial States: 0 Estimated model order: 19 N4Weight: CVA Enforce Stability: on Result: Fit to estimation data: % To: q A x Magnitude (db) x y To: q B To: q A From: f A x Receiver Receptance; db Reference= 10-6 m/n From: f A y Measurement Data Estimated Model From: f B x From: f B y To: q B y Frequency (Hz) Integration of measured receptance into a time domain 22

23 Comparison in the frequency domain X A B Y Admittance Matrix Receiver (db Reference = 10-9 m/ns) Magnitude (db) y x y x To: q Y To: q Y To: q X To: q X From: f X x From: f X y Reference 4x4 translational coupled measured estimation Frequency (Hz) Eigenfrequencies of the 4x4 estimated from measurement paired Eigenfrequencies lower 95% deviation upper 95% deviation frequency fit Eigenfrequencies of the reference model Integration of measured receptance into a time domain 23

24 Structure of the presentation Motivation New Approach Test models Final assembly based on measured data Conclusion Integration of measured receptance into a time domain 24

25 First approach car body : Yaw Damper connection Car body: Triaxle acceleration measurement Yaw damper -150 From: In(1) Bode Diagram From: In(2) From: In(3) To: Out(1) measured estimated Magnitude (db) To: Out(2) To: Out(3) Frequency (Hz) Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 25

26 Outlook Challenges: Suitable measurement of the experimental test model Just looking at few connection points perfect measurement is needed System identification of MDof models Problems with strongly coupled structures Consideration of the mass properties of the substructure Extrapolation connection points with rotational DoF Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 26

27 Advantages and Chances Chances: Combining linear acoustic models with Multi Body Simulation Looking at transient behavior instead of just steady state Using general sub models Not restricted to modal models Possible domain overlapping: Combining structure and airborne sound field using vibroacoustic transfer functions Significantly simplified representation of large weakly coupled structures Applications in other fields Extension to non linear sub models possible (using Functional Mockup instead of State Space) Integration of measured receptance into a time domain simulation of a Multi Body Model using SIMPACK 27

28 Thankyoufor your attention! Dipl.-Ing. Johannes Woller Wissenschaftlicher Mitarbeiter Technische Universität Dresden Fakultät Maschinenwesen Institut für Festkörpermechanik Professur Dynamik und Mechanismentechnik Dresden Tel.: