This paper constructs a flat heat pipe model suitable for medium and low temperature thermal energy storage scenarios (50-150?C). The pipe is 200 mm long and 50 mm wide, and uses a copper-based wick (porosity 0.65) and deionized water as the working fluid. The COMSOL simulation analysis is performed. Results show that at a heat source temperature of 100?C and a heat load of 500 W, the temperature difference between the center and edge of the evaporator reaches 17?C. In contrast, the temperature difference in the condenser is only 3?C. Heat transfer efficiency increases with heat load, reaching 89.2% at 800 W under 100?C, significantly higher (p < 0.05, one-way ANOVA) than 86.1% at 80?C and 88.5% at 120?C. Heat storage capacity reaches a maximum of 14,580J at a tube length of 200 mm and a porosity of 0.65, a 13.6% increase over the 150 mm tube length model, calculated as (14580-12840 J)/12840 J?100%. The 10-hour heat loss rate is 5.1% at a porosity of 0.65. While the loss rate is slightly lower (4.8%) at a lower porosity (0.55), the heat storage capacity is insufficient. This study provides a parameter optimization basis for heat pipe design in medium and low temperature waste heat recovery systems.
Zheng et al. (Thu,) studied this question.