Spray &

   Imaging

   Group

Spray Diagnostics   &   Advanced Imaging

Liquid breakup of a water jet

 

The main goal of this work is to provide an extensive open access image database where fluid mechanics researchers and modellers have access to experimental evidences of the mechanisms responsible for water jet breakups. A single injector orifice of 625 µm in diameter is used and water is injected in quiescent air at ambient temperature and atmospheric pressure conditions. In this study, only the liquid pressure of injection is varied and reach a maximum Reynold number of ~60 000.

 

While most high-speed videos of liquid breakups are usually based on shadowgraphy imaging, the approach proposed here consists in recording liquid LIF (Laser Induced Fluorescence), which provides faithful images of the formed liquid bodies.

 

The experiment is divided into two parts:

 

  • In the first part, the viewed area has a distance of 160 mm along the vertical direction of the jet and series of ~800 images are recorded at 40 000 frames per second corresponding to a temporal resolution of 25 µs.

 

  • In the second part, the viewed area has a distance of 30 mm only along the vertical direction. This configuration provides higher spatial resolution and allows resolving finer structures of the jet, where series of ~400 images are recorded at 50 000 frames per second corresponding to a temporal resolution of 20 µs. In this case, two high-speed cameras orientated at 90˚are used to simultaneously image the liquid jet. This two-angle detection configuration allows the identification and more accurate description of the irregular liquid bodies.