In this experimental study, our group focused on analyzing the heat transfer characteristics and the axis-switching phenomenon for impinging elliptic jets with high aspect ratios (AR = 10 and 14). The study used hot-wire anemometry to measure the flow characteristics of synthetic jets (SJs) and infrared thermal imaging to study heat transfer. I performed the experiments and processed and analyzed the results on MATLAB.

When an SJ is ejected through a non-axisymmetric orifice, the shape of the jet fluctuates as it flows downstream due to self-induced deformations of the vortex rings. This phenomenon of the rotation of the jet shape in symmetric vortex rings is called axis switching.

Results 

• Higher AR jets (AR = 10, 14) perform better cooling at lower z/D values compared to circular jets, especially in the near-field region.

• Axis switching is observed even in high aspect ratio elliptic jets, indicating significant changes in the jet shape during downstream travel.

Outcomes

This work resulted in a paper that was presented at the Fluid Mechanics and Fluid Power Conference 2022.

Understanding the Heat Transfer characteristics and Axis Switching phenomenon in High Aspect Ratio Elliptical orifice impinging Synthetic Jets

Fluid Mechanics and Fluid Power, Volume 1, FMFP 2022 DOI