Thermodynamic Equations of Nonequilibrium System for Measuring Odors by Gas Analyzers. Practical Example of a Microcontroller Calculation for Digital Odor Detection by Gas Analyzers
Abstract
A method for the digital measurement of odors using gas analyzers is presented. This capability enables a new level of precision in identifying spoiled products (e.g., in grain storage and transportation), detecting narcotics, digitizing odors in the culinary and cosmetics industries, and developing olfactory television. This paper details a measurement approach and methodology based on thermodynamic equations for a nonequilibrium odor measurement system. A practical example of a microcontroller calculation for a digital odor detection device using MQ-type gas analyzers is provided, including the process for determining the empirical coefficients integrated into the algorithm.
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Introduction
First, we must define what constitutes a measurable odor and how its digital detection can solve practical problems. An odor is manifested by the release of specific volatile organic compounds (VOCs) into the air. These VOC plumes, which form an odor's signature, propagate at characteristic speeds through a complex atmospheric environment. Their dispersion is influenced by factors including weight (molar mass), volume, temperature, humidity, incident light spectrum, air velocity, and other dynamic parameters that also affect biological olfactory receptors. While animals and humans use biological receptors to assess edibility or quality, digital odor detection provides an objective, quantifiable alternative. The application of odor analyzers allows for the determination of quality in products such as meat, fish, and grain. Specifically, this technology can identify the causes of spoilage in grain within elevators and shipholds, detect narcotics at security checkpoints in airports and customs, and has potential uses in creating odor-based multimedia and other fields.
Conclusion
1) An approach and methodology based on thermodynamic equations for a nonequilibrium system have been developed for the digital measurement of odors using gas analyzers.
2) Thermodynamic equations for the digital odor detection system have been formulated. Experiments were conducted to determine the empirical coefficients (E₁-E₅) for a range of target odors, including narcotics, spoilage in grain, and spoilage in meat/fish products.
3) A practical example of the microcontroller calculation algorithm for a thermodynamic gas analyzer has been provided, demonstrating the integration of the empirical coefficients into the device's operational logic.