Innovative image processing evaluation of infrared obscuration efficiency in red phosphorus-based compositions under varying loading pressures

Airborne obscurants based on red phosphorus (RP), used as smoke-producing agent, are effective infrared obscuration countermeasures for military operations. This study investigates the significant influence of various loading pressures (P = 4, 4.5, and 5 tons) and target (black-body radiator) temperatures (T = 50, 100, 150, and 200 °C) on the infrared obscuration efficiency of selected RP-based smoke composition using a novel evaluation approach based on image processing techniques. The selected composition consists of 61% red phosphorus, 4% lead oxide, 25% magnesium, and 10% epoxy resin by weight. A thermal camera operating in the far-infrared region (8–12 µm) and advanced image processing algorithms were used to measure the infrared obscuration efficiency of the tested compositions. The algorithms implemented using Python and the CV2, OS, and Matplotlib libraries, enabled pixel-based intensity analysis to detect variations in infrared images over time and precisely assess the smoke screen’s effectiveness in obscuring the target’s image and temperature. Among the tested samples, P3 (5 tons) achieved the best thermal performance of 110 °C after 49 s. It provided the highest obscuration efficiency of 95%, with a minimum formation time of 4 s and a successful duration of 39 s, compared to P1 (4 tons) and P2 (4.5 tons). Furthermore, T1 (50 °C) demonstrated superior obscuration efficiency over T2 (100 °C), T3 (150 °C), and T4 (200 °C), validating the effectiveness of image processing techniques as an innovative evaluation tool.