Generation of stable multi-jets by flow-limited field-injection electrostatic spraying and their control via I-V characteristics

The I-V characteristics of flow-limited field-injection electrostatic spraying (FFESS) were investigated, exposing a new way to predict and control the specific spraying modes from single-jet to multi-jet. Monitoring the I-V characteristics revealed characteristic drops in the current upon formation of an additional jet in the multi-jet spraying mode. For fixed jet numbers, space-charge-limited current behaviour was measured which was attributed to space charge in the dielectric liquids between the needle electrode and the nozzle opening. The present work establishes that FFESS can, in particular, generate stable multiple jets and that their control is possible through monitoring the I-V characteristics. This can allow for automatic control of the FFESS process and expedite its future scientific and industrial applications. (fast track communication)