Influence of the Radial Clearance of a Squeeze Film Damper on the Vibratory Behavior of a Single Spool Gas Turbine Designed for Unmanned Aerial Vehicle Applications

Table 4

Logarithmic decrements calculated for the six first natural frequencies of the rotor-bearing system.

Rotational speed	1FW; mode	1BW; mode	2FW; mode	2BW; mode	3FW; mode	3BW; mode
55.56	5.0437	5.2713	0.2024	0.0216	0.8447	0.8903
111.11	3.3526	3.8727	0.4609	0.0234	0.7276	0.7742
166.67	1.0670	2.4758	1.3331	0.0453	0.6332	0.5997
222.22	0.3705	1.7818	1.3666	0.0743	0.5428	0.4473
277.78	0.1605	1.2929	1.0972	0.1012	0.4522	0.3222
333.33	0.0779	0.9097	0.8126	0.1171	0.3563	0.2216
388.89	0.0419	0.6765	0.6255	0.1460	0.3253	0.1705
444.44	0.0256	0.4636	0.4822	0.1671	0.2886	0.1283
500	0.0171	0.3288	0.3251	0.1720	0.2445	0.0934