## 6 Conclusions  
This study successfully proposed and validated a new technology for storing volume in the horizontal section of dry hot rock U-shaped wells, providing an innovative solution for effective dry hot rock energy development. By conducting hydraulic fracturing and acidizing in the horizontal section and sealing the rock interface with high-temperature liquid metal, this technology not only optimizes the heat exchange process but also achieves efficient energy conversion using low-melting-point liquid alloys as the heat transfer medium.  
Furthermore, it thoroughly explores factors influencing rock interface stability in the horizontal section of U-shaped wells, including formation stress, thermal shock stress, as well as the gravity and pressure effects of liquid alloys. Establishing failure criteria for the rock interface lays a theoretical foundation for the application of storage technology in the horizontal section of U-shaped wells.  
The study also analyzed the parameter sensitivity of rock stability at the interface of dry hot rock formations, indicating that adjusting the depth of the horizontal section can effectively maintain rock interface stability. These findings will provide important guidance for U-shaped wells' design and optimization.  
Moreover, research shows that cyclic thermal shock decreases rock tensile strength. However, by increasing pump injection pressure, the rock interface stability can be effectively maintained. These findings validate the feasibility and efficiency of storage cavity technology in the continuous extraction of dry hot rocks.  
In summary, the findings of this study offer a new technological path for the efficient development of dry hot rock energy. They also provide important theoretical and practical guidance for future research and application of dry hot rock extraction technologies.  
However, the rocks in the hot dry rock reservoir contain various minerals, which may undergo chemical reactions with alloys in high-temperature environments, potentially causing chemical corrosion to the alloys, leading to a decrease in their strength, and leakage of high-efficiency heat exchange fluid in the channels. Therefore, studying the chemical reactions between alloys and rocks in hot dry rock reservoirs and proposing measures to improve the alloys is necessary.  
Writing--original draft, Y.X. ([PERSON]); writing--review & editing, B.X., S.W., C.F., S.M., F.X. and Y.X. ([PERSON]). All authors have read and agreed to the published version of the manuscript.  
Figure 5: The following line graph shows variations in pump injection pressure with the decrease in rock tensile strength.  
**Funding:** This research was supported by the key project \"Research on Key Technologies for Exploration and Development of Geothermal Resources\" (Project Number: 2022 DJ5503) of the China National Petroleum Corporation.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.  
**Acknowledgments:** We sincerely thank funders for their support.  
**Conflicts of Interest:** The authors declare no conflict of interest.