Turbulence and Complex Flow Phenomena in Axial Turbomachines
Abstract
The objective of this project is to measure the flow within turbomachines, and use the data for addressing relevant turbulence-modeling issues. A unique two-stage, axial turbomachine test facility has been constructed. It contains liquid (66% NaI, 34% H2O) with an optical index of refraction that matches that of the acrylic blades of the second stage. Consequently, it allows unobstructed view on the flow within the rotor, stator and the gap between them. Two and three dimensional velocity measurements can be performed using 2-D PIV and 3-D HPIV. The 2-D measurements are in progress and samples are provided. In the meanwhile we use PIV data generated in a centrifugal pump with a vaned diffuser to examine the flow at three modeling levels: Passage-averaged steady RANS, Unsteady RANS, and subgrid scale modeling for LES. Distributions of Reynolds, deterministic and SGS stresses within the impeller and the diffuser are determined and discussed. A new model is introduced for the deterministic stresses that accounts for interactions between the non-uniform outflux from one blade row with the neighboring blades. The model reproduces the correct magnitude of stresses occurring due to unsteady leading-edge separation in the diffuser.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2000
- Accession Number
- ADA389616
Entities
People
- Charles Meneveau
- Joseph Katz
Organizations
- Johns Hopkins University