... May 11, 19 72. ) 20 8 Gas Turbine Engineering Handbook //INTEGRA/B&H/GTE/FINAL (26 -10-01)/CHAPTER 5.3D ± 21 2 ± [178 21 8/41] 29 .10 .20 01 3:57PMis apparent that a forcing frequency of 12, 000 rpm ... Engine Group,Group Engineering Division, May 11, 19 72. ) 21 0 Gas Turbine Engineering Handbook //INTEGRA/B&H/GTE/FINAL (26 -10-01)/CHAPTER 6.3D ± 23 0 ± [21 9 27 4/56] 29 .10 .20 01 3:59PMFor nonprewhirl ... onset. 2. Axisymmetric 2. Eliminates instability.3. Damping Introduce damping. 20 4 Gas Turbine Engineering Handbook //INTEGRA/B&H/GTE/FINAL (26 -10-01)/CHAPTER 5.3D ± 20 7 ± [178 21 8/41] 29 .10 .20 01...