Design optimization of cold storage for agricultural product using corner curvatureand thermal backup system: A case study on brinjal and tomato

Abstract

In the field of post-harvest management, cold storage systems have been critical for preserving temperature-sensitive crops like brinjal and tomato. Traditional rural cold storage models have faced critical drawbacks, including poor thermal mixing due to sharp-cornered chamber geometries, which has created airflow stagnation and thermal blind spots. To eliminate these zones, the proposed cold room has featured 150 mm curved corners within an 2438 × 1828 × 1981 mm³ chamber with an insulation of 100 mm polyurethane foam (PUF) for enhancing vertical circulation and reducing corner induced stratifications. Furthermore, conventional setups that has utilized secondary refrigerants like water has faced hydro-mechanical resonance due to unregulated fluid-compressor interactions. To address this, the proposed storage unit has integrated a thermal backup system comprising a PCM-buffered 500-liter water tank with phase-decoupled circulation, thereby mitigating mechanical stress and ensuring temperature stability during compressor downtime. Further, a failure to dynamically monitor and respond to microclimatic shifts has resulted in the preservation of shadow sectors. To overcome this, an AHT10 sensor array has been installed at different positions to track actual airflow, temperature, and humidity across storage zones of uniformly arranged crates. Experimental analysis has shown improvements with a reduced temperature rise from 7.4 °C to 5.8 °C during power cuts, minimized produce weight loss of 6.5%, and a lower energy consumption of 3.6 kWh during 14 days, have confirmed the system’s effectiveness in extending the shelf life of the agricultural produce.