Formation and Characteristics of Liquid Bells Over Conical Angled Impactors.

A falling liquid jet striking a conical impactor forms a radially expanding sheet, resulting in a bell-like structure known as a Savart bell (Savart, F. 1833). Here, we experimentally investigate the shape and stability of liquid bells, as it depends upon the flow rate Q, impactor angle φ, and flow history. High-speed imaging was used to capture the bell shape over a range of impactor angles (0° to 25°) and jet flow rates (0 to 4.5 L/min). The Weber number (We) defines the flow with higher We producing large bells that can be sustained at significantly lower flow rates during a decreasing Q sweep leading to a wide range of shapes not observed during an increasing Q sweep. For example, the bell width exhibits a non-monotonic relationship with Q leading to multiple stable bells with the same height.