SS-V: 6010 Simply Supported Thin Square Plate - Periodic Forced Vibration Response

Test No. VD02 View transient response of a simply supported square plate subjected to periodic forced vibration .

Definition

A simply supported thin square plate 10 x 10 x 0.05 m is subject to uniform pressure P=100 Pa which changes in time as the following function.

P=100*( sin( ωt )sin( 3ωt ) ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGqbGaeyypa0JaaGymaiaaicdacaaIWaGaaiOkamaabmaabaGa ci4CaiaacMgacaGGUbWaaeWaaeaacqaHjpWDcqGHxiIkcaWG0baaca GLOaGaayzkaaGaeyOeI0Iaci4CaiaacMgacaGGUbWaaeWaaeaacaaI ZaGaeqyYdCNaey4fIOIaamiDaaGaayjkaiaawMcaaaGaayjkaiaawM caaaaa@50CE@

Where,
ω = 2 P I f MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacqaHjpWDcqGH9aqpcaaIYaGaey4fIOIaamiuaiaadMeacqGHxiIk caWGMbaaaa@40B2@
f = 1.2 H z MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGMbGaeyypa0JaaGymaiaac6cacaaIYaGaamisaiaadQhaaaa@3E9D@
Excitation frequency.

Sixteen (16) modes are used to approximate dynamics solution and 2% modal damping is assumed in all modes.

The material properties are:
Properties
Value
Modulus of Elasticity
2.e+11 Pa
Poisson's Ratio
0.3
Density
8.e+3 kg/m3

Results

The plate is simulated as a 3D solid body. Spot-lines were created at the mid-plane of the plate in order to apply hinge supports (Figure 1). In order to simulate periodic load changing according to the formula above, two pressure loads were applied to the plate:
  • P = 100 sin ( ω t ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGqbGaeyypa0JaaGymaiaaicdacaaIWaGaey4fIOIaci4Caiaa cMgacaGGUbWaaeWaaeaacqaHjpWDcqGHxiIkcaWG0baacaGLOaGaay zkaaaaaa@45C6@ to the top surface of the plate, and
  • P = 100 sin ( 3 ω t ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGqbGaeyypa0JaeyOeI0IaaGymaiaaicdacaaIWaGaey4fIOIa ci4CaiaacMgacaGGUbWaaeWaaeaacaaIZaGaeqyYdCNaey4fIOIaam iDaaGaayjkaiaawMcaaaaa@4770@ to the bottom surface of the plate
Figure 1.


The following table contains typical values at steady-state portion of the dynamics solution (Figure 2).
Deflection Y, mm Surface Stress, MPa
-2.886 2.062 SimSolid, solid model
-2.863 2.018 Reference, thin plate model
Figure 2.


1 Test 13P from NAFEMS Publication R0016, “Selected Benchmarks for Forced Vibration” J. Maguire, D.J. Dawswell, L. Gould