Atomization of High-Viscosity Fluids for Aromatherapy Using Micro-heaters for Heterogeneous Bubble Nucleation

Area of Science:

• Materials Science
• Mechanical Engineering
• Fluid Dynamics

Background:

• Traditional atomizers struggle with a wide range of fluid viscosities.
• Existing technologies often involve lead-based components, posing environmental and health concerns.

Purpose of the Study:

• To develop a novel, lead-free microelectromechanical-system (MEMS) atomizer.
• To investigate the performance of a thermal bubble actuation mechanism for atomization.
• To assess the device's applicability across a broad spectrum of fluid viscosities.

Main Methods:

• Fabrication of a MEMS-based atomizer utilizing thermal bubble actuation.
• Systematic testing across fluid viscosities from 1 cP to 200 cP.
• Optimization of micro-heater dimensions and micro-cavity size.
• Particle Image Velocimetry (PIV) for droplet analysis.

Main Results:

• The lead-free MEMS atomizer operates efficiently with low power consumption (~1W) and a high atomization rate (0.1-0.3 mg/cycle for DI water).
• Achieved effective atomization for fluids ranging from water to oil-like substances.
• Droplet diameters ranged from 30-90 μm at speeds of 20-340 mm/s.
• Novel spraying modes were identified and characterized.

Conclusions:

• The developed MEMS atomizer is a cost-effective, environmentally friendly, and versatile solution for fluid atomization.
• Its ability to handle high viscosity fluids opens new application possibilities.
• This technology has the potential to significantly impact the atomizer market and related industries.