Modeling the Main Physical Processes in Beehives

Abstract

Abstract—A winter bee community of 15 000 bees housed in wooden beehive boxes with 12 frames was used to analyze the physical processes that occur in beehives. The most important specific feature of this study is assessment of the changes in the size of the bee cluster during overwintering and the relationship between temperature, humidity, and air flows in the beehive. The physical processes in hives were simulated using the Comsol 5.3 software package. The temperature fields confirm the high heat insulating ability of bees. The temperature on the external surface of winter cluster was +12°C. Despite the changes in the temperature outside the cluster, the temperature inside it was stably maintained at +25 to +32°C. The inside temperature of the winter cluster was nonuniform, with some local foci of up to but not exceeding +34°C, which is safe for the bees. Analysis of the air flows showed a velocity of 0.03–0.1 m/s at the entrance to the hive and of 0.12–0.17 m/s at the central opening. The highest velocity was recorded inside the cluster (over 0.19 m/s). The moisture distribution in the hive was as follows: the moisture content in the incoming air was 0.04 mol/m3 and in the outgoing air it was 0.5–0.6 mol/m3, which is explainable by elimination of the moistened air from the bee cluster. The images of the moisture distribution in hive elements prove the agreement between the saturation rate of wooden walls and the humidity of the boundary air.