Free Vibration of Rectangular Plates with Porosity Distributions under Complex Boundary Constraints

Table 6

Fundamental frequencies for porous rectangular plates subjected to different elastic edge conditions with different porosity coefficients (e = 0.2, a/b = 0.5, and h/b = 0.2).

Type	Mode no.	Boundary conditions
		E^1E^1E^1E^1	E^2E^2E^2E^2	E^3E^3E^3E^3	E^4E^4E^4E^4	E^5E^5E^5E^5
I	1	0.3998	0.3829	0.3546	0.3539	0.3534
	2	0.5972	0.3912	0.3828	0.3828	0.3828
	3	0.6238	0.5052	0.3912	0.3912	0.3912
	4	0.7756	0.6237	0.4614	0.4611	0.4603
	5	0.8752	0.7059	0.5052	0.5052	0.5052
II	1	0.3998	0.3829	0.3556	0.3549	0.3544
	2	0.5973	0.3912	0.3829	0.3829	0.3829
	3	0.6292	0.5052	0.3912	0.3912	0.3912
	4	0.7823	0.6292	0.4633	0.4631	0.4623
	5	0.8753	0.7059	0.5052	0.5052	0.5052
III	1	0.3997	0.3828	0.3542	0.3536	0.3531
	2	0.5969	0.3911	0.3828	0.3828	0.3828
	3	0.6220	0.5050	0.3911	0.3911	0.3911
	4	0.7735	0.6220	0.4608	0.4606	0.4598
	5	0.8740	0.7055	0.5050	0.5050	0.5050