Relationship Between Airflow and Static Elimination Performance of EIESD Ionizing Bars

Relationship Between Airflow and Static Elimination Performance of EIESD Ionizing Bars

1. Introduction

Airflow (wind speed) plays an important role in enhancing ion transport from the ionizing bar to the target surface.

Optimizing airflow improves decay time, ion distribution, and overall static neutralization efficiency, especially on large surfaces or in low-humidity environments.

2. How Airflow Affects Static Elimination

Airflow Condition Effect on Ionization

No airflow (still air) Ions disperse mainly by diffusion; decay time is slower, especially on distant or uneven surfaces

Moderate airflow (air-assisted bar) Speeds up ion transport, reduces decay time, improves coverage

High airflow (strong fan or blower) Can significantly shorten decay time; may cause uneven ion distribution if directed incorrectly

Turbulent airflow Disrupts uniform ion distribution; can cause residual charge in some areas

3. Benefits of Controlled Airflow

Faster static decay: Increased ion transport shortens decay time on insulative surfaces.

Improved ion coverage: Airflow ensures ions reach areas farther from the bar.

Enhanced performance in dry environments: Low humidity reduces natural ion mobility; airflow compensates.

Reduced particle attraction: Faster neutralization prevents surfaces from retaining static charges that attract dust.

4. Operational Guidelines

Factor Recommendation

Distance from bar Maintain manufacturer-recommended working distance (typically 20–50 cm)

Fan speed Moderate speed usually sufficient; adjust to avoid turbulence or uneven ionization

Direction Direct airflow evenly across the target area for uniform neutralization

Large surfaces Consider multiple bars or adjustable airflow to cover entire area

Low-humidity conditions Air-assisted ionizers help maintain effective decay times

5. Typical Performance Impact

Configuration Decay Time (to ±100 V, 25 cm distance, 50% RH)

Standalone DC bar (no airflow) 2–5 seconds

Air-assisted DC bar (moderate airflow) 1–3 seconds

AC bar, low airflow 5–10 seconds

Strong turbulence / misaligned airflow Uneven decay; some areas >10 seconds

Properly controlled airflow is especially important in cleanrooms, large plastics sheets, or conveyor lines.

6. Summary Table

Airflow Factor Effect on Static Elimination Guidelines

No airflow Slow decay; ions spread by diffusion Only for small targets or short-range use

Moderate airflow Faster decay; uniform ion distribution Optimal for most production lines

High airflow Very fast decay; may cause uneven ionization Adjust fan direction and speed carefully

Turbulent airflow Uneven ion coverage; residual charges Avoid turbulence; direct airflow evenly

Key Takeaways:

Moderate, well-directed airflow improves ion transport and decay speed.

Excessive or turbulent airflow can cause uneven ion distribution, leaving residual charges.

Air-assisted ionizing bars are especially effective in low-humidity or large-area applications.