Numerical Investigation of Turbulent Junction Flows
Abstract
Large-eddy simulations for a canonical junction flow geometry (Rood wing) were carried out for a Reynolds number based on approach flow velocity and maximum thickness of 7,000. The mean flow data were in good agreement with particle image velocimetry measurements at Penn State University. Instantaneous flow visualizations reveal a forward and backward motion of the horseshoe vortex and an intermittent loss of coherence. Upstream boundary layer events which were detected with the variable-interval time-averaging method, were found to be correlated with an intermittent strengthening of the horseshoe vortex. To test if the bimodal behavior is correlated with upstream boundary layer events, pulsed disturbances were deliberately introduced upstream of the junction. The correlation between the forced boundary layer events and the circulation of the horseshoe vortex was weak which may be attributed to the chosen forcing method. In addition, simulations with two different circular endwall fillets were carried out. In accordance with the literature, the fillets were found to suppress the bimodal behavior. In summary, the present results support earlier research that suggests that the bimodal behavior is triggered by upstream boundary layer events.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2019
- Accession Number
- AD1091959
Entities
People
- Andreas J. Gross
- John-paul G. Mosele
- Zachary D. Robison
Organizations
- New Mexico State University