Evaluation of a proposed velocity equation for improved exothermic process control

Area of Science:

• Industrial Hygiene
• Occupational Safety
• Heat Transfer

Background:

• Exothermic processes pose significant health risks to millions of American workers annually due to excessive heat and contaminants.
• Engineering controls are crucial for mitigating these hazards, with evolving theories in heat transfer and meteorology informing their design.

Purpose of the Study:

• To develop and validate a new equation for estimating buoyant plume mean velocity in exothermic processes.
• To compare the accuracy of the proposed equation against existing models, including the American Conference of Governmental Industrial Hygienists (ACGIH) and Hemeon equations.

Main Methods:

• A proposed equation for buoyant plume mean velocity was developed based on refined heat transfer and meteorological theories.
• Plume velocity data were collected from laboratory and field experiments involving exothermic processes.
• Statistical tests (t-tests and Wilcoxon Signed Rank tests) were used to compare experimental data with predictions from the proposed, ACGIH, and Hemeon equations.

Main Results:

• The ACGIH mean velocity equation showed significantly different estimates compared to collected laboratory and field data.
• The proposed and Hemeon equations provided solutions that were not significantly different from the experimental data.
• Radiant heat flux was identified as a critical factor influencing plume mean velocity estimations.

Conclusions:

• The proposed equation and the Hemeon equation are more accurate for estimating plume mean velocity than the currently recommended ACGIH equation within the investigated parameter range.
• Findings highlight the importance of considering radiant heat flux in heat transfer models for industrial hygiene applications.
• Improved plume velocity estimation can lead to more effective engineering controls for exothermic processes, enhancing worker safety.