PRESENTATION OF THE UNIVERSITY OF FEDERAL ITAJUBÁ

Transcription

1 PRESENTATION OF THE UNIVERSITY OF FEDERAL ITAJUBÁ The Federal University of Itajubá-UNIFEI, founded on 23 November 1913, under the name of Institute of Mechanical and Electrical engineering Itajubá-IEMI, personal initiative Theodomiro Carneiro Santiago's lawyer, was the tenth School of Engineering to settle in the country. It has two campuses: Itajubá, MG - headquarters and Itabira, MG, advanced campus. Campus - Itajubá Campus - Itabira

2 PRESENTATION OF THE UNIVERSITY OF FEDERAL ITAJUBÁ COURSES OFFERED BY THE GRADUATION IEM Campus Itajubá: MECHANICAL ENGINEERING; MECHANICAL ENGINEERING - AIRCRAFT; ENGINEERING MATERIALS and ENGINEERING POWER.

3 PRESENTATION OF THE UNIVERSITY OF FEDERAL ITAJUBÁ COURSES OFFERED IN GRADUATE - IEM: MASTER IN MECHANICAL ENGINEERING; MASTER PROFESSIONAL ENGINEERING OF MATERIALS and PHD IN MECHANICAL ENGINEERING. SITE:

4 JOB TITLE ACTIVE CONTROL STRUCTURE TYPE BEAM USING PIEZO ELECTRIC ACTUATORS IN ANSYS Author Master : Ribeiro.A.R.B Co - Author : Phd Junior.L.J.J

5 DESCRIPTION OF THE PROBLEM Consists of performing dynamic analysis and active control of a beamlike structure using piezoelectric actuators through the ansys APDL language.

6 METHODOLOGY Beam: modeled using the cubic element SOLID45. Figure 2 - element SOLID45.

7 METHODOLOGY PZT: element SOLID5 Figure 3 - element SOLID5.

8 METHODOLOGY SOLID45 e SOLID5 Table 1. Dimensions and distances to create the beam, actuator and sensor. Dimensions of the structure type beam (mm) Dimensions actuator (mm) Distance actuator (mm) Distance actuator (mm) 504x25.4x0.7 72x25.4x Table 2. Properties of aluminum and pzt. Modulus of elasticity of aluminum (GPa) Poisson's ratio Density of aluminum (kg/m 3 ) Density of PZT (kg/m 3 )

9 Beam clamped free. METHODOLOGY Figure 4 configuration of the beam.

10 METHODOLOGY In this topic we will with the permittivity of the ceramic, piezoelectric strain matrix and another matrix as shown in the following table: Table 4. Permittivity of ceramics. Permittivity in direction(x) Permittivity in direction(y) Permittivity in direction(z) 15.03E E-9 13E-9

11 METHODOLOGY Table 5. Matrix deformation piezoelectric [e]. TBDATA TBDATA TBDATA TBDATA TBDATA 16,17 14,17 3,-6.5 6, Table 6. Matrix elasticity [c]. TBDATA TBDATA TBDATA TBDATA TBDATA 1, 126E9, 79.5E9, 84.1E9 7, 126E9, 84.1E9 12, 23.3E9 19, 23E9 21, 23E9

12 ANSYS APDL!*** Data of the beam ***! HEIGHT =.7E-3! direcao Z WIDTH=25.4E-3! direcao Y COMPR=504E-3! direcao X mx=42! n. blocos na direcao x my=4! n. blocos na direcao y mz=1! n. blocos na direcao z DX=COMPR/mx DY=WIDTH/my DZ= HEIGHT /mz

13 ANSYS APDL!*** Data of the PZT ***! DSA=DX HEIGHT A=.61E-3! direção Z WIDTHA=25.4E-3! direção Y COMPRA=72E-3! direção X nx=6! n. blocos na direção z ny=4! n. blocos na direção x nz=1! n. blocos na direção y DXA=COMPRA/nx DYA=WIDTHA/ny DZA= HEIGHT A/nz

14 ANSYS APDL!First generate the material 2 and use the command VATT (piezo).! Generating ny blocks in y direction. *DO,i,1,nx *DO,j,1,ny *DO,k,1,nz BLOCK,DSA+(i-1)*DXA,DSA+i*DXA,(j-1)*DYA,j*DYA,ALTURA+(k- 1)*DZA,ALTURA+k*DZA *ENDDO *ENDDO *ENDDO VATT,2,,2

15 ANSYS APDL! Automatically be material 1! Generating ny blocks in y direction (beam) *DO,i,1,mx *DO,j,1,my *DO,k,1,mz BLOCK,(i-1)*DX,i*DX,(j-1)*DY,j*DY,(k-1)*DZ,k*DZ *ENDDO *ENDDO *ENDDO ESIZE,DSA! gera outros blocos de dimensões proporcionais. NUMMERG,ALL! merge pontos duplicados. NUMCOMP,ALL! comprime elementos. VMESH,ALL! geração da malha.

16 ANSYS APDL! NODE AT THE BOTTOM OF PZT NSEL,S,LOC,Z,,ALTURA NSEL,R,LOC,X,DSA,DSA+COMPRA CP,1,VOLT,ALL! acopla o DOF volt aos nos da superfície inferior e sup. dos PZT. CM,AREAUP,NODE! cria componentes para a superfície inferior. *GET,N1,NODE,,NUM,MIN! NODE ON TOP OF PZT NSEL,S,LOC,Z,ALTURA+ALTURAA CP,2,VOLT,ALL CM,INTRFC,NODE *GET,N2,NODE,,NUM,MIN

17 ANSYS APDL! Restrictions DOF STRUCTURE NSEL,S,LOC,X,0 D,ALL,UZ DSYM,SYMM,X DSYM,SYMM,Y NSEL,ALL FINISH /SOLU! Modal Analysis ANTYPE,MODAL MODOPT,LANB,3 MXPAND,3 TOTAL,100 SAVE SOLVE FINISH

18 METHODOLOGY Beam and PZT sensor. Figure 4 Beam, actuator and sensor.

19 Modal Analysis. METHODOLOGY Figure 5, first mode of vibration.

20 Modal Analysis. METHODOLOGY Figure 6, second mode of vibration.

21 Modal Analysis. METHODOLOGY Figure 7, third mode of vibration.

22 METHODOLOGY Results of natural frequencies (Hz) obtained analytically and by Ansys. Table 8. Experimental Analysis. Case First Second Third Table 9. Ansys Results. Case First Second Third

23 METHODOLOGY We will make a transient analysis where a force is applied against time at the end of the beam, this system will suffer the influence of a proportional controller with the objective of reducing the vibrations that occur in the structure.

24 METHODOLOGY Controlling structure using a proportional controller, with the gain Kc = 2. Figure 8, proportional control.

25 METHODOLOGY Controlling structure using a proportional controller, with the gain Kc = 3.3 Figure 9, proportional control.

26 METHODOLOGY Controlling structure using a proportional controller, with the gain Kc = 5. Figure 10, proportional control.

27 CONCLUSION A computer simulation using Ansys proved very effective in comparison with the analytical results in the analysis of natural frequencies and vibration active control using a proportional controller.

28 FUTURE WORK For future work we intend to implement other types of controllers such as PID controller and fuzzy. And conduct a new analysis to know which of the two will be more evetivo controllers for active control of vibrations.

29 REFERENCES H KARAGÜLLE, L MALGACA AND H F ÖKTEM. Analysis of active vibration control in smart structures by ANSYS, Smart Mater. Struct. p , 18 May RAO, SINGIRESU S. Vibrações Mecânicas. Editora Pearson Prentice Hall, OGATA KATSUHIKO. Engenharia de Controle Moderno. Editora Pearson Prentice Hall, 2003.