The effect of flare geometry on the flow field generated by radial-radial swirlers

Download
2023-1-27
Bay, Ayşe
An experimental investigation is conducted to assess the impact of the flare geometry on the mean flow field generated by radial-radial swirlers. Two-dimensional two-component PIV measurements are performed on the mid-plane of a non-reacting planar combustor test section. A baseline geometry without a flare is compared to four swirlers with three different flare geometries. Analysis of the time-averaged flow fields reveals that there is an increase in radial velocity values and a decrease in axial velocity values as a result of the introduction of the flare geometry, which results in a sudden expansion of the swirling jet. When different flare geometries are compared, almost identical flow fields are observed and the formation of a CRZ is not observed for any configuration that employs a flare geometry. Although the maximum negative axial velocity values decrease for geometries with flare, due to the increase of the recirculation radius, the recirculating mass flow rate is higher than the baseline swirler. On the other hand, the recirculating mass flow rate is higher in the co-rotating swirler configuration due to a stronger adverse pressure gradient along the central axis of the jet when compared to the counter-rotating configuration. High TKE regions are observed at shear layers between the swirling jet and the CTRZ as well as the swirling jet-CRZ for the Baseline-CR. Regions of high TKE generate intense mixing regions. Coherent flow structures are identified by using the snapshot POD method and different mode shapes obtained for swirlers with and without flare geometry are reported. It is shown that the change in the sense of rotation and flare geometry does not bring about any differences in the POD modes and their energy contents for the given swirl number and confinement conditions.

Suggestions

Effect of Flare Geometry on the Flow Field of Radial-Radial Swirlers
Bay, Ayse; Kiyici, Firat; Perçin, Mustafa (2022-01-01)
In this study, an experimental investigation is conducted to assess the impact of the flare geometry on the mean flow field generated by radial-radial swirlers. Two-dimensional two component PIV measurements are performed on the mid-plane of a non-reacting planar combustor test section. Three dimensional numerical simulations are conducted for selected cases to support experimental observations. In a previous study conducted in the same setup, counter-rotating radial-radial swirlers without flare extension ...
The effect of sample size turbulence intensity and the velocity field on the experimental accuracy of ensemble averaged PIV measurements
Uzol, Oğuz (null; 2001-09-19)
A statistical analysis of the PIV data, obtained inside the near wake of a staggered 2-row array of circular cylinders, is performed for the investigation of the effect of sample size, turbulence intensity and the velocity field on the ensemble-averaged data. The PIV measurements are performed at two diameters downstream inside the wake. The ensemble averaged velocity field is obtained using 700 vector maps. The experiments are conducted for a Reynolds number of 10000 based on the inlet velocity and the cyl...
Transformation of flow structure on a delta wing of moderate sweep angle during pitch-up maneuver
Yavuz, Mehmet Metin (2012-08-01)
The transformation of flow structure on a delta wing of moderate sweep angle is investigated during pitch-up via quantitative imaging in crossflow planes, in relation to qualitative dye visualization. The comparisons are made with the corresponding stationary wing. The effects of different pitch-up maneuver rates and Reynolds numbers on evolution of flow patterns are also addressed. A technique of high-image-density particle image velocimetry is employed for the quantitative analysis. The transformation of ...
The effect of structural variability and local site conditions on building fragility functions
Sisi, Aida Azari; Erberik, Murat Altuğ; Askan Gündoğan, Ayşegül (2018-04-01)
In this study, the effect of local site conditions (site class and site amplifications) and structural variability are investigated on fragility functions of typical building structures. The study area is chosen as Eastern Turkey. The fragility functions are developed using site-specific uniform hazard spectrum (UHS). The site-specific UHS is obtained based on simulated ground motions. The implementation of ground motion simulation into seismic hazard assessment has the advantage of investigating detailed l...
An empirical expression for the determination of mean critical flow velocity in slurry transporting pipeline systems
Göğüş, Mustafa (1999-09-10)
In this study, the effect of solid particle settling velocity on the mean critical mixture-flow velocity in a pipeline system is investigated. A graphical method proposed by Mitzmager (1964), for a quick and reliable calculation of particle-settling velocity, is used in the analysis. Following dimensional analysis applied on the main parameters of the problem the most suitable non-dimensional form of critical flow velocity is obtained from the application of regression analysis on the available data. Compar...
Citation Formats
A. Bay, “The effect of flare geometry on the flow field generated by radial-radial swirlers,” M.S. - Master of Science, Middle East Technical University, 2023.