The analyzer establishes a balance between electrical force and gas-drag force. Particles whose mobility matches the selected operating condition follow the permitted path to the outlet, whereas particles with different mobility are directed away and removed. This trajectory-based selection converts a mixed airborne population into a mobility-resolved fraction for subsequent concentration measurement.
Adjusting the applied voltage or the gas-flow conditions changes which electrical mobility satisfies the force-drag balance. Scanning these settings therefore moves the selected mobility range across the sample rather than measuring only one class. Recording concentration at each setting produces a mobility distribution that can be related to particle diameter.
Electrical mobility reflects how a charged particle responds to the electric field relative to its drag in the gas. Consequently, the classified signal contains information connected to both charge and particle size, rather than representing diameter alone. Interpreting a mobility distribution requires recognizing this relationship when analyzing aerosol or nanoparticle populations.
A sample containing airborne particles or ions is introduced into a controlled gas flow and exposed to the analyzer's electric field. The voltage or airflow is varied to select different mobility classes, and the particle concentration emerging from the outlet is measured at each condition. The resulting sequence of measurements forms the mobility distribution.
The essential arrangement includes a controlled gas stream, electrodes that create the electric field, an outlet for the selected trajectory, and a concentration measurement step. Stable control of the gas flow and systematic adjustment of voltage or airflow determine which particles reach the outlet, allowing the measured signal to be associated with a defined mobility condition.
Applications include aerosol characterization, nanoparticle analysis, atmospheric studies, and instrument calibration. The measurements also support investigations of particle formation, transport, and reaction behavior by showing how particle populations are distributed by mobility and how those populations can be related to diameter, charge, or composition. These uses connect gas-phase particle behavior with chemical analysis.