One machine, several measurement channels.
The proposed platform brings together a controlled fog flow, a treatment region, upstream and downstream observations, a water receiver and an energy ledger. Its purpose is to determine what changes when a defined intervention is applied. The apparatus is in development; the illustrations are explanatory schematics.
Each channel answers a different question. Optical measurements quantify attenuation along a specified path. Wet particle sizing describes the population the optics encounter. Airflow and temperature measurements reveal changes in exposure. A balance measures water arriving at the receiver. Electrical metering measures demand at the declared system boundary.
The baseline belongs inside the design.
| Condition | Electrical action | Collector | Question |
|---|---|---|---|
| A | Off | Absent | What is the untreated reference for charge-only exploration? |
| B | On | Absent | What changes when charge is introduced without a collecting surface? |
| C | Off | Present | What does the passive hardware do? |
| D | On | Same as C | What does electrical operation add? |
The primary proposed comparison is D versus C. It preserves the collector geometry while changing electrical operation. A and B address a distinct exploratory question. Treating every powered condition as equivalent would erase information about what performs the removal. The versioned protocol controls the actual procedure. Weatherhill protocol W1 →
Normalize changing inlet conditions.
rpowered = βout,powered / βin,powered
Illustrative reduction = 100 × [1 − rpowered / rpassive]Use qualified positive upstream measurements and transit-aligned observations. A negative reduction represents worsening normalized extinction. This single-comparison equation is not a significance test or a pass/fail decision.
If fog becomes thinner before a treatment begins, the outlet may look clearer even when the treatment did nothing. An inlet reference helps identify this. The time delay between the inlet and outlet also matters: simultaneous clock timestamps need not represent the same passing air.
Qualification comes before effectiveness.
- Check the optical system. Characterize background, alignment, linear response, drift, stray light and window contamination.
- Characterize the fog and flow. Document size coverage, missing measurement tails, flow uniformity, temperature, humidity and baseline stability.
- Measure reset behavior. Establish how long prior conditions affect the next run through retained water, wet surfaces or lingering charged populations.
- Declare the comparison. Fix outcomes, order allocation, exclusions, uncertainty treatment and the conditions that qualify a valid run.
- Separate discovery from confirmation. Settings selected using exploratory data need fresh data for their confirmatory evaluation.
Repeated readings are not independent experiments.
Thousands of readings during one preparation share the same environment and many of the same errors. They describe the run well, but they do not create thousands of independently prepared trials. Weatherhill’s proposed analysis uses a day-level structure and explicit systematic-bias treatment.
Report both the effect and its uncertainty. A result that is smaller than an unresolved instrumental bias cannot carry a strong physical claim. If one sensor, one location or one preparation drives the effect, that finding guides further investigation rather than being hidden inside an average.
From laboratory finding to useful application.
A successful instrument test would be one step. A field study must establish spatial reach, persistence under replacement flow, operating range and reliability. A commercial decision also needs maintenance demand, whole-system cost, water quality where relevant and a clearly defined customer outcome.
The proposed protocol, build brief, calculation tools and literature are published. This section does not present measured Weatherhill hardware performance or imply that the planned instrument is already available for booked testing.