Experimental study on the influence of the liquid and air thicknesses on a planar air-blasted liquid sheet

B. Déjean (1) , P. Berthoumieu (1) , P. Gajan (1)

1 ONERA - The French Aerospace Lab [Toulouse]

This experimental study is devoted to the analysis of an air-blasted atomizer behavior whose air and liquid thicknesses are changed. Variation of liquid thickness is realized by modifying the injector inside; when for air thickness, wedges are introduced in the air flow duct. Using different experimental methods: tomography and shadowgraphy visualizations, oscillation frequency and breakup length are measured and studied. Thickness of each fluid has not the same influence depending on each atomization process parameter. Breakup length is strongly correlated to liquid thickness; when frequency depend more on air thickness. But more than air thickness, for the frequency especially, the flow configuration plays the most significant role, through influence of boundary layer characteristics as wall shear stress. This study highlights the necessity of another non dimensional number than the momentum flux ratio (MFR). This new number could complete the physical description of the phenomenon by taking into consideration some geometrical aspects of the injector and some physical variables characterizing the air flow configuration.

Mots clés: ATOMIZATION; LIQUID SHEET; THICKNESS INFLUENCE

Domaines: Sciences de l'ingénieur [physics]

B. Déjean, P. Berthoumieu, P. Gajan. Experimental study on the influence of the liquid and air thicknesses on a planar air-blasted liquid sheet. 25th European Conference - Liquid Atomization & Spray Systems - ILASS 2013, Sep 2013, CHANIA, Greece. ⟨hal-01058399⟩