Avaliação do desempenho térmico de câmaras de refrigeração em hipermercado

Abstract

Thermal control in cold storage chambers of hypermarkets is a key determinant of food safety and the operational efficiency of refrigeration systems. This study evaluated the thermal and operational performance of four cold storage chambers in a hypermarket located in the state of Paraná, Brazil, by comparing actual operating conditions with theoretical thermal load modeling. The methodology was based on continuous temperature monitoring using data loggers over three 96-hour sampling campaigns, combined with thermal load and refrigeration capacity simulation using CalCooling software. The results revealed distinct non-conformity profiles among the evaluated chambers. Chamber 1 (Refrigerated Meats) exhibited thermal instability characterized by nighttime super-cooling and excessive temperature increases during peak traffic periods, associated with obstructed air circulation and frequent door openings. Chamber 4 (Frozen Products) operated continuously outside the ideal freezing range, with severe non-conformity attributed to the accumulation of cardboard packaging that compromised heat exchange. Chamber 5 (Meat Thawing) showed satisfactory sanitary compliance, but presented an oversizing of refrigeration capacity of 105.1% relative to the calculated demand, resulting in low energy efficiency. Chamber 8 (Fruits, Vegetables and Greens) required a refrigeration capacity of 3,506 W according to CalCooling, a value 18.4% higher than originally specified, a condition aggravated by continuous hot air infiltration caused by the absence of a rigid door at the chamber entrance. It is concluded that the thermal deviations and energy inefficiency identified result from a combination of structural failures, inadequate operational control, and chamber usage dynamics, with the integration of sound dimensioning, continuous monitoring, and good operational practices being essential to ensure thermal stability and the safety of stored food.