Experiments were conducted to study the effects of several important factors on the performance of a refrigerated display cabinet, including ambient air temperature, indoor relative humidity, ambient air flow, air supply velocity, air flow from perforated back panels and night covers. Both inside temperature distribution and heat load were investigated. Furthermore, the thermal entrainment factor is correlated with Reynolds number and Richardson number. The results show the thermal entrainment tends to increase with increasing momentum force but decrease when the gravitational force is dominant. (c) 2004 Elsevier Ltd. All rights reserved.