Research Article

Free Vibration Analysis of Rotating Pretwisted Functionally Graded Sandwich Blades

Table 6

Nondimensional frequency parameters for the first six modes of FG sandwich blade with varying twist angle (, , , and ).

Mode10°15°20°25°30°45°50°60°

1st4.52334.53424.53424.52064.50414.49354.47434.40204.36054.3245
2nd27.963328.079927.917827.462126.871626.171525.416722.964322.186020.7649
3rd28.310628.205028.515429.156529.995531.343933.063338.004039.997044.6692
4th75.938675.744775.380774.884174.512073.851773.093770.837970.163068.9817
5th79.303579.700980.757682.028484.032986.777489.279298.6081101.9785107.9219
6th87.585287.911488.968090.582792.883995.972599.5237112.9271118.0741130.0957