魏民1. Convective heat transfer of air flow in cold cabinet with two-fluid model[J]. CIESC Journal, 2012, (S1): 138-144.
DOI:
魏民1. Convective heat transfer of air flow in cold cabinet with two-fluid model[J]. CIESC Journal, 2012, (S1): 138-144.DOI: 10.3969/j.issn.0438-1157.2012.z1.025.
Convective heat transfer of air flow in cold cabinet with two-fluid model
The convective heat transfer of the cold cabinet was investigated by using two-fluid model after the effectiveness of new model was confirmed. This study includes the influence of wind speeds,wind directions and speeds of air curtain. The results show that the convective heat transfer is improved along with increasing of the wind speed. In a relatively short time,there is a linear relationship between convective heat transfer and time. The wind direction has small effect on heat transfer when it is less than about 15° while has appreciable impact and made an increase of energy consumption by approximately 30% when it reaches 30°. The air curtain,a major constituent of the refrigeration system of cold cabinet,provides a barrier of moving air across a door opening and reduces heat transfer by preventing the penetration of hot air. The simulation shows that there is the minimum speed and the best speed range of air curtain. The air curtain can not be formed when the speed is less than 1.5 m·s-1,while has a large spillover of cold air when it is greater than 3.0 m·s-1. From the above,the best speed of air curtain ranges from 2.6 m·s-1 to 3.0 m·s-1.