城市地下综合管廊通风传热模型

为了优化地下管廊的通风设计，降低运行费用，建立苏州某地下管廊（UUT）一典型段的通风传热的解析模型. 考虑舱间传热、空气和廊壁的耦合传热以及土壤边界厚度的影响. 通过与计算流体动力学（CFD）模型的比较，验证解析模型的可靠性. 结果表明，廊内热源、通风换热和向土壤传热是影响舱内温度的主要因素，舱间传热的影响相对较小. 考虑降温需求的各舱室最低通风量受热源强度、进风温度（大气温度）和土壤温度影响较大，实际管廊最低通风量的计算须结合当地气象条件和管廊热源强度. 对于苏州地区地下综合管廊试验段，满负荷运行的电力舱和热力舱的最低通风换气次数分别为10、5次/h，而无热源的水信舱和燃气舱均可以按现行规范要求的最低换气次数设计通风量. 对于其他布置形式的管廊，可以采用类似的解析模型进行分析.

Ventilation and heat transfer modeling in urban utility tunnel

An analytical model for ventilation and heat transfer in one typical urban utility tunnel (UUT) section in Suzhou was developed in order to aid the design and optimization of the ventilation system of the UUT for reduction in ventilation energy. The model includes the heat transfer among neighboring cabins, the conjugate heat transfer at the tunnel walls, and the thickness of the overlaying soil layer. The analytical model was validated by comparing it with the computational fluid dynamics (CFD) model. Results show that the internal heat source, ventilation, and soil temperature are the most important factors on cabin temperature, with the inter-cabin heat transfer a minor factor. The minimum ventilation rate to prevent over-heating of cabins is strongly dependent on the heat source strength, the inlet temperature (atmospheric temperature), and the soil temperature. Therefore, the minimum ventilation rate of UUT in other areas should be calculated according to the local meteorological conditions and the actual heat source intensity of the tunnel. The minimum ventilation rates, in air change rate, of the fully loaded cable cabin and the steam pipe cabin were 10 h^?1 and 5 h^?1, respectively, in the test section of UUT in Suzhou area. The minimum ventilation rate specified in the current code for UUT can meet the temperature control requirement for cabins without any heat sources. A similar analytical modelling approach can be used to analyze the ventilation requirement for UUT with other layouts of cabins.