Identification of Engine Inertia Parameters and System Dynamic Stiffness via In Situ Method

Table 2

Identified system stiffness of the curve bar spring.

	Direction
FEM system stiffness (N/m)		2695193	0	536118.7	0	44461.07	0
		0	275302	0	9247.395	0	−69097.7
		536118.7	0	1416128	0	85055.21	0
		0	9247.395	0	22965.87	0	−13059.3
		44461.07	0	85055.21	0	37323.23	0
		0	−69097.7	0	−13059.3	0	41700.41
Estimated system stiffness (N/m)		2686950.3	−67.8	536001.9	80395.7	313059.6	−403005.1
		61.9	272706.3	63.0	−18142.7	15.7	−68023.4
		539171.3	−36.3	1419722.6	212926.3	139301.4	−80845.6
		80788.2	−18181.8	212693.0	55748.0	20843.2	−18336.2
		313161.1	4.2	138468.0	20756.3	73034.6	−46970.4
		−403015.0	−68262.8	−80467.7	−18264.8	−46967.9	101906.0
Error (%)		0.31	—	0.02	0.03	0.29	0.32
		—	0.94	—	0.77	—	1.55
		−0.57	—	−0.25	−0.24	−0.46	−0.53
		−0.46	0.55	−0.13	−0.03	−0.21	−0.68
		0.26	—	0.14	0.21	0.18	0.27
		0.31	1.21	−0.06	−0.29	0.27	0.43