Abstract
dc:description.abstractAn analytical investigation of dynamic compressor characteristics was conducted with the goal to make fundamental improvements in the modeling of dynamic compressor stage characteristics. It was determined that present state-of-the-art in modeling dynamic compressor stage characteristics is the use of steady-state characteristics derived from flow model calculations, with first-order time lag response functions applied to account for dynamic departures from the steady and quasi-steady performance predictions. This investigation developed a blade frequency response function (FRF) method for describing the dynamic blade response. Once the frequency response function of a blade row has been determined, any time or spatially dependent, non-uniform flow can be applied and the model will predict the dynamic blade response. The first step of this research was to develop FRFs based on first-order lag equations and to test the method using these simple transfer functions. The next step was to develop FRFs based on a dynamic blade lift model for a simple, idealized compressor blade row model. It was found that chord length has a strong influence on the FRF, which is related to the fluid transport time through the blade passage. The final step was to incorporate experimental data obtained from a study of dynamic wake response of an isolated rotor. It was assumed that the wake response was well correlated with the dynamic lift response of a blade row. It was found that aerodynamic loading, distortion strength, and span position all influence the frequency response functions, which differ greatly from simple first-order lag equations. It was determined that a number of FRFs are needed to describe the dynamic blade response accurately.
Degree
thesis:*- Name thesis:degree_name
- Master of Science
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Mechanical Engineering
- Department dc:contributor.department
- Mechanical Engineering
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 1999
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Howard, Joseph S. III
- Chair dc:contributor.committeechair
-
- O'Brien, Walter F. Jr.
- Committee members dc:contributor.committeemember
-
- Dancey, Clinton L.
- King, Peter S.
Subjects
dc:subject × 6Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-060299-183959
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/33391