Numerical study on thermal-work conversion performance of dynamic system driven by temperature difference between evaporation and condensation

Bowen Zhang, Yonggang Lei, Ming Wu, Yao Yan, Yonghui Wang, Dongwei Zhang and Chao Shen

Energy, 2025, vol. 334, issue C

Abstract: The extensive use of fossil fuels has led to significantly environmental pollution and climate change. Therefore, there is an urgent need for developing renewable energy technologies and efficient methods to upgrade low-grade thermal energy. In this study, a novel dynamic system driven by temperature difference is proposed, incorporating a drinking bird mechanism coupled with mechanical transmission to convert waste heat into gas displacement. The effects of condensation cooling methods, cooling temperature, wind speed, and filling rate on the performance were studied through numerical simulations. Among the cooling configurations tested, mechanical ventilation and cooling water evaporation (MV-CWE) mode demonstrated the highest efficiency. Gas displacement increased continuously with decreasing condensation temperature, reaching a peak value of 0.781 cm3/s for natural convection and radiation heat transfer (NC-RHT) conditions. The system exhibited stable operation at extreme conditions, maintaining functionality at 243.75 K across a broad range of filling rates (16 %–88 %). For the MV-CWE mode, higher wind speeds led to enhanced gas displacement, with consistent performance maintained over a filling rate range of 26 %–82 %. The relationship between gas displacement and filling rate displayed a non-monotonic trend, indicating a trade-off between the working fluid mass and the liquid column height induced by the pressure difference. This design provides a promising approach for utilizing evaporation-condensation phenomena in waste heat recovery, and establishes a theoretical and practical basis for the development of thermally driven energy conversion systems.

Keywords: Evaporation and condensation; Thermal-work conversion; Waste heat recovery; Drinking bird; Gas displacement (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S036054422503381X
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:334:y:2025:i:c:s036054422503381x

DOI: 10.1016/j.energy.2025.137739

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().