Technical Substantiation of ULV Atomization
for Comprehensive Air Remediation

1Equipment and Physical Specifications

The remediation process utilizes a high-output ULV Atomizer to generate a population of liquid droplets with a Volume Median Diameter (VMD) of 20–50 μm.

Fluid Dynamic Regime

These droplets operate within the Stokes Flow regime (Reynolds Number Re ≪ 1). In this state, the viscous forces of the air dominate over gravity and inertia, allowing the droplets to remain buoyant for an extended period, maximizing the "Time-of-Flight" through the contaminated air mass.

Scientific Equivalence

This droplet spectrum is physically identical to "cloud droplet" populations modeled in atmospheric research (Marinescu et al., 2017). Consequently, the fluid dynamics governing atmospheric cleansing are directly applicable to the indoor environment.

2Primary Mechanism: Collision-Coalescence

The efficiency of the "volumetric sweep" is driven by the Stochastic Collection Equation. Because the atomizer produces a range of droplet sizes, they descend at varying terminal velocities, creating a collision matrix for particle capture.

Droplet Velocity Characteristics

Physical Capture Process

As the larger, faster "collector" droplets descend, they physically overtake and collide with smaller particles and droplets in their path. This collision leads to coalescence—merging smaller contaminants into a larger, heavier liquid mass that settles out of the breathing zone and onto surfaces for removal.

3Targeting the 90%: Brownian Diffusion for UFPs

While larger particles are caught by direct impact, Ultrafine Particles (UFPs) (0.003 μm – 0.1 μm) are too small to be captured by inertial collision alone. Instead, they require capture through Brownian Diffusion.

Diffusive Capture Mechanism

Technical validation from Hampl et al. (1971) confirms that as a collector droplet falls, it creates a streamline in the air. UFPs, which exist in constant, random Brownian motion, oscillate across these streamlines and become trapped within the droplet's capture zone.

Péclet Number Correlation

The collection efficiency (E) for these smallest particles is inversely proportional to the velocity. The slower-moving droplets in a ULV cloud provide the necessary residence time for UFPs to "diffuse" into the droplet's surface. This ensures that the 90% of airborne particles typically missed by filters are effectively scavenged.

4Gas-Phase Scavenging and VOC Absorption

Indoor air quality is often further degraded by Volatile Organic Compounds (VOCs) and other gaseous pollutants. ULV atomization extends beyond particulate removal to address these chemical vapors through liquid-gas phase interactions.

Henry's Law Application

The partitioning of gases into liquid droplets is governed by Henry's Law, which describes the equilibrium between gas and liquid phases. By atomizing liquid into billions of 20–50 μm droplets, the system creates a massive liquid-to-gas surface area for molecular absorption.

Molecular Sink Mechanism

As the droplets descend, they act as mobile "sinks," absorbing water-soluble gaseous pollutants from the air. This mirrors the atmospheric "wet deposition" process, where natural fog or rain cleanses the air of chemical vapors. The continuous movement ensures contact with the entire air volume.

5Environmental Optimization and Reliability

To ensure a "Reliable Basis" for remediation, the service accounts for complex indoor variables that can affect droplet performance and treatment efficacy. Environmental conditions significantly influence droplet behavior and must be actively managed.

Turbulent Activation Enhancement

Research (Prabhakaran et al., 2020) indicates that droplet activation—the process of a droplet remaining "wet" and effective—is enhanced by turbulence. The atomizer's blower creates localized "Turbulent Eddies," ensuring the cloud reaches every corner and maintains efficacy even in sub-saturated (low humidity) environments.

Thermal Stratification Management

Rising heat can create a "thermal cap" that prevents standard air cleaners from reaching the ceiling. The mechanical force of the ULV atomizer breaks these thermal layers, ensuring the 20-foot "cloud depth" required for total vertical sweep from floor to ceiling.

Humidity Optimization ("Drying Effect" Mitigation)

In environments with Relative Humidity (RH) < 40%, droplets evaporate faster, potentially reducing efficacy. Service protocols maintain effectiveness by monitoring RH and adjusting flow rates to ensure droplets maintain sufficient mass to complete the scavenging cycle before evaporation.