A Frequency Domain Analysis of Surface Heat Transfer/Free-Stream Turbulence Interactions in a Transonic Turbine Cascade
Abstract
The relationship of time resolved surface heat flux to the turbulent free stream flow over a turbine blade is investigated. Measurements are made in a transonic linear cascade with a modern high pressure turbine blade profile. Time resolved direct heat transfer measurements are made with Heat Flux Microsensor (HFM) inserts along the pressure side, and with one HFM directly deposited on the suction surface near the leading edge. Simultaneous velocity measurements are made above the heat flux sensors using miniature hot wire probes. Grids are used to produce two turbulence fields of constant inlet turbulence intensity, Tu=5%, but significantly different integral length scales (Ax). Results are compared with a low free stream turbulence baseline condition. Special emphasis is given to frequency domain analysis of the data via coherence function magnitude and phase, energy spectra, and time auto and cross correlations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1996
- Accession Number
- ADA342506
Entities
People
- David G. Holmberg
Organizations
- Virginia Tech