The airflow distribution through a porous medium such as horticultural crops is a great challenge. The development of a method allowing the measurement of the air velocity or its distribution would be of large interest. The applicability of using instrumented balls as an indirect measurement of air velocity was evaluated. A group of 64 instrumented plastic balls were used as horticultural produce simulators and strategically distributed in an orthogonal matrix along with other 448 plastic spheres to simulate precooling of column stacked produce. The ball matrix was submitted to cooling process under controlled conditions. Correlations were determined by measuring the half-cooling time of 64 simulators positioned at fixed locations inside of the two-end-fully-open ball matrix. The surrounding air velocity was inferred as a function of the simulator locations in reference with the air entrance. 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