Visualize the path around equipment—not through a risk review
Airflow around racks, cabinets, machines and thermal-management systems is shaped by fan direction, cable openings, panels, obstructions, pressure zones and nearby exhaust. A visible tracer can make those interactions easier to understand.
Do not introduce water-based or chemical fog near energized, high-voltage, optical, vacuum, sterile or moisture-sensitive equipment without written approval.
Common equipment-airflow problems
Exhaust recirculation
Does warm discharge return to the intake instead of leaving the equipment zone?
Blocked intake
Are filters, walls, cables, panels or adjacent equipment restricting entry?
Competing fans
Do cabinet, room and process fans create unstable or reversed paths?
Bypass flow
Does air pass around the intended heat-transfer or filtration path?
Enclosure leakage tendency
Where does air visibly enter or exit around seams and penetrations?
Maintenance state
Does an open panel, removed filter or temporary duct change the pattern?
Pair visualization with quantitative thermal data
| Evidence layer | What it contributes | Typical limitation |
|---|---|---|
| Fog video | Direction, mixing, recirculation and source-to-destination path. | Qualitative; affected by source momentum and tracer behavior. |
| Temperature mapping | Thermal gradients, hot spots and response over time. | Does not identify the entire airflow path by itself. |
| Velocity / flow measurement | Quantitative local airflow data. | Point measurements can miss larger patterns. |
| Pressure measurement | Differential pressure across panels or zones. | Does not show the route the air follows. |
| Control and fan data | Operating state, speed and command context. | May not reflect actual delivered performance. |
Reduce avoidable damage and misleading results
Review the equipment
Identify energized surfaces, moisture limits, sensors, optics, filters, process exposure and warranty restrictions.
Choose the least intrusive tracer
Use minimum output, distance and duration—or a different technology when water is unacceptable.
Establish baseline data
Capture temperature, fan state and pressure before fogging.
Observe externally first
Start outside the equipment boundary before considering any internal introduction.
Stop on condensation or alarm
Do not continue if surfaces become wet, sensors react unexpectedly or visibility compromises safe operation.
Questions this page should settle
Is ultrasonic DI-water fog safe for electronics?
Not automatically. It contains microscopic water droplets and requires equipment-specific moisture and electrical review. Keep distance, output and exposure as low as possible or use another approved method.
Can fog replace thermal imaging?
No. Fog shows a path; thermal imaging shows temperature patterns. The combination can be useful when both methods are appropriate.
Turn the airflow question into an equipment specification.
Send the environment, scale, purity constraint, target visibility, delivery geometry, runtime and operating restrictions. Applied Physics can compare current ultrasonic and LN₂ platforms without treating one model as a universal answer.