多年冻土地区储罐地基热虹吸系统研究

Study of Thermosyphon System for Storage Tank Foundation in Permafrost Regions

依据倾斜成组埋于地基中的热虹吸管,建立了多年冻土储罐地基热虹吸系统的计算模型和热流程图,通过试算初步确定了热虹吸管的直径、冷凝段翅片面积和间距。计算结果显示,寒季热虹吸系统可使融土全部回冻,同时还可降低多年冻土温度,且当蒸发段长度超过20 m后,热虹吸制冷量将不再显著增长。研究表明,多年冻土地区储罐地基热虹吸系统可满足储罐安全运行的地基承载力和变形要求。若在热虹吸系统上布置正交方格网状的均温热虹吸,可使罐底地基土温度均匀,在环墙底部增设隔热板则可减小夏季罐底融化深度。

According to sloping-thermal-siphon groups that buried in foundation, the calculation model and heat flow chart of the therosyphon system for storage tank foundation in permafrost regions are established.Then the diameter,fin areas of condenser section and spacing of thermal siphons are preliminarily determined by trial. The calculation results show that thawing soil can be totally re-frozen by therosyphon system in cold seasons, and the temperature of permafrost can be decreased at the same time.Meanwhile,the therosyphon refrigerating capacity will not increase remarkably if the length of evaporation section is more than 20 m.The study shows that thermosyphon system for storage tank foundation in permafrost regions can meet the foundation bearing capacity and deformation requirements for the safety running of storage tanks.If uniform temperature therosyphon with orthogonal square nets can be put on the top of thermosyphon system,the temperature of foundation soil under tanks will be uniform,and heat shields under the ring wall can decrease melting depth under tanks in summer.