To address the issues of high energy consumption and low efficiency associated with electric heating defrosting in air‑cooled refrigerator evaporators,a dynamic CFD defrosting model was established.This model was used to investigate the melting characteristics of various tube rows operating under a constant power mode.Using the mass of melted frost as a quantitative indicator,the defrosting process was divided into six sub‑stages.Based on the principle of dynamic matching between frost load and heat supply,five stepped power reduction strategies were designed to explore the effects of variable power on defrosting energy consumption,efficiency,and the improvement of heat distribution.The results indicate that all variable power strategies achieve varying degrees of improvement compared to the constant power mode.Among them,the power step reduction strategy 1 based on the entire defrosting process performs the best.It reduces defrosting energy consumption by 14.49%,increases defrosting efficiency by 5.72%,reduces average defrosting power by 35.27%,and reduces defrosting residual heat by 19.09 kJ.This study can provide a reference for the design of variable power control strategy for electric heating defrosting systems in air‑cooled refrigerator evaporators.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |