Turbomachinery Rotordynamics:

Modeling, Analysis and Reporting Overview

Authors

Dustin
Pavelek, P.E.

Ray Kelm,
P.E.

Kelm
Engineering, LLC – Houston, TX

Abstract

This paper will provide an
overview of the modeling, analysis and reporting process for lateral rotordynamics
of turbomachinery.  The paper will focus
on the application of the newly published API Technical Report 684-1 (API
Standard Paragraphs Rotordynamic Tutorial: Lateral Critical Speeds, Unbalance
Response, Stability, Train Torsionals, and Rotor
Balancing, First Edition, November 2019). 

Lateral rotordynamics for the typical
equipment used in Ethylene plants such as steam turbines and centrifugal
compressors with fluid-film bearings will be examined.  Using excerpts from previous rotor studies, both
correct and incorrect results that can be produced by failing to follow good
engineering practices in rotor model creation, bearing coefficient calculation,
unbalance response analysis and lateral stability analysis will be discussed.  The Torsional Analysis and Balancing sections
of API TR 684-1 will not be discussed in this paper.

The intended audience for this
presentation includes engineers that are tasked with evaluating a lateral
rotordynamic analysis report produced by an equipment manufacturer or third party consultant during procurement of new machinery
or design changes for existing equipment.