Page 209 - Steam Turbines Design, Applications, and Rerating

188 Chapter Ten

tory bearing test facilities to make running tests with various types of
full-size bearings to confirm the analytical results. As a consequence of
the testing, the accuracy of bearing analysis is very high. But experi-
mentation and analysis have gone further. Impedance tests have been
made on the bearing support structures to confirm the design stiffness
calculations and to provide realistic dynamic stiffness values for the
rotor dynamics model.
Finally, special rotor vibration response tests have been made on a
large number of turbines of various sizes and speeds to correlate the
rotor dynamics results with actual performance. Rotor response tests
on new turbine designs ensure that subsequent field operation will be
successful.