Kriging Metamodeling in Rotordynamics: Application for Predicting Critical Speeds and Vibrations of a Flexible Rotor

Table 17

% of the relative errors on the variance of the critical speeds for different regression orders and correlation functions. Symmetric case with 120 samples.

	Gaussian	Linear	Exponential	Cubic
Zero-order regression
	(25.51; 1.20)	(200.21; 4.72)	(129.81; 2.94)	(291.40; 9.58)
	(9.48; 1.78)	(38.07; 2.60)	(12.38; 2.10)	(59.18; 3.69)
	(5.94; 1.36)	(8.29; 1.47)	(6.23; 1.42)	(6.71; 1.72)
	(7.34; 1.35)	(14.29; 1.61)	(10.05; 1.57)	(18.11; 1.91)
	(0.86; 0.14)	(2.49; 0.22)	(1.81; 0.18)	(3.06; 0.39)
	(0.08; 0.02)	(4.24; 0.22)	(1.25; 0.07)	(7.63; 0.60)
	(0.07; 0.01)	(2.50; 0.11)	(1.70; 0.05)	(3.21; 0.26)
	(0.01; 0.00)	(0.88; 0.04)	(0.22; 0.01)	(1.50; 0.11)
First-order regression
	(26.08; 1.28)	(66.92; 1.76)	(48.14; 1.62)	(91.56; 2.29)
	(7.91; 1.67)	(8.13; 1.81)	(6.51; 1.82)	(11.12; 2.11)
	(6.59; 1.38)	(7.02; 1.43)	(6.00; 1.42)	(9.47; 1.57)
	(6.06; 1.35)	(5.35; 1.38)	(5.54; 1.43)	(5.74; 1.42)
	(0.82; 0.14)	(1.72; 0.16)	(1.46; 0.16)	(2.46; 0.20)
	(0.07; 0.02)	(2.01; 0.05)	(1.67; 0.05)	(2.71; 0.09)
	(0.05; 0.01)	(0.92; 0.03)	(0.71; 0.02)	(1.24; 0.05)
	(0.00; 0.00)	(0.04; 0.00)	(0.03; 0.00)	(0.05; 0.00)
Second-order regression
	(12.27; 1.24)	(19.57; 1.26)	(13.73; 1.27)	(35.00; 1.61)
	(6.09; 1.65)	(5.08; 1.65)	(5.34; 1.67)	(5.18; 1.67)
	(7.34; 1.41)	(8.74; 1.43)	(7.63; 1.44)	(6.79; 1.46)
	(5.81; 1.33)	(5.59; 1.34)	(5.63; 1.37)	(6.04; 1.35)
	(0.83; 0.14)	(0.80; 0.15)	(0.80; 0.15)	(0.82; 0.16)
	(0.07; 0.02)	(0.16; 0.02)	(0.14; 0.02)	(0.25; 0.03)
	(0.04; 0.01)	(0.07; 0.01)	(0.07; 0.01)	(0.10; 0.01)
	(0.00; 0.00)	(0.01; 0.00)	(0.01; 0.00)	(0.01; 0.00)