耦合了潮涌相变换热的多孔介质土体与地铁空气间能量互动演化机理及应用研究

The scientific laws governing the effects of soil heat storage and release around subway stations and tunnels on the air thermal environment are still not clear and urgent to be revealed, because it is the fundamental reason leading to the long-term and widespread problems, such as the high energy consumption in station air-conditioning systems, excessive temperature rise in subway tunnels, and the simple designing process in subway thermal environment control system. Taking the soil around the station and tunnels as a whole, this project abstracts the scientific study topic of “the interactive evolution of the energy between the soil and the surrounding air with the action of the three cycle air waves from the outdoors, the interval, and the station”. Meanwhile, based on the long-term observation and prudent scientific reasoning, the scientific proposition, " the tide transformation heat phenomena in the porous medium soil near the subway wall surface", is put forward for the first time as an essential supplement for the theoretical gap. On the basis of the coupling model of the revealed continuous interactive heat exchange and discrete tide heat transfer between soil and air, a long-term prediction model of the subway air temperature, wall temperature, and soil mass storage capacity is to be established under typical climatic zones, geological conditions, and subway structure sizes. Based on this, a dynamic strategy is to be proposed to regulate the interval air temperature in summer and to stabilize the station air temperature during non-air-conditioning seasons. Furthermore, a four-parameter strong-coupling model with air temperature, wall temperature, background wind velocity, and equipment capacity is to be put forward innovatively, providing the theoretical support for energy-saving and comfortable, refined design and operation is subway. The study work in this project has important scientific significance, as well as the long-term application value.

地铁车站、区间周围土体蓄放热对空气热环境随年限影响的科学规律尚不明确是导致目前车站空调系统能耗大、区间温升过高和设计方式简单粗放等问题长期广泛存在的本质所在，亟待解决。此项目将区间车站周围土体抽象为统一整体，凝练出“室外、区间、车站三个空气波作用下土体与所围空气之间能量周期互动演化机理”的科学问题，同时基于长期观察和审慎科学推理首次提出“近壁面多孔介质土体潮涌相变换热”的科学命题，填补部分理论空白。在揭示上述土体与空气间耦合连续互动换热和离散潮涌换热科学规律基础上，拟建立典型气候区、地质条件和地铁结构尺寸下，区间车站空气温度、壁面温度、土体蓄放热量随运营年限的预测模型。并依此为抓手，给出区间温升调控、非空调季节车站气温维稳的动态策略，创新性的提出地铁“空气温度、壁面温度、背景风速、设备容量”四参数强耦合组合模型，为地铁环控节能舒适、精细化设计运营提供理论支撑，具有重要的科学意义和应用价值。

本项目基于交通强国和双碳减排国策背景，聚焦“室外、区间、车站三个空气波作用下土体与所围空气之间能量周期互动演化机理”和“近壁面多孔介质土体潮涌相变换热”两个科学问题，开展如下科研工作。第一部分，一方面，通过缩尺模型试验、Champs_Bes数值模拟，现场实测，研究了地铁区间隧道半无限大土体随运营年限的蓄放热特性，并创新性的建立了区间气温随运营年限演化特性的迭代求解数学模型，由研究结果可知区间土体温度场在第10年左右趋于稳定，上海夏季轨行区的最高气温会超过40℃，1，2，3月份区间隧道夜间通风有利于缓解夏季区间气温超标的问题。另一方面，通过缩尺模型试验、anasys三维数值模拟和现场实测，研究了在室外、室内和区间隧道三个以年为周期的空气温度波作用下，车站土体蓄放热随运营年限的演化特性，进而通过车站空气热平衡模型机理，创新性地建立了车站气温随运营年限演化特性的迭代求解数学模型。上述两部分成果为长期利用地铁区间隧道和车站土体中蕴藏的自然冷源提供了重要的技术参考。第二部分，本项目基于长期的车站实测，创新性的提出了车站近壁面围岩土体潮涌相变换热的科学假想，并进一步通过模型试验、数值模拟和理论建模，探讨了多孔介质土体发生潮涌相变换热的机理、临界条件和特性，极具理论上的创新性、填补了部分学术研究的理论空白。如当秋冬季节室外大幅降温时，实测中站厅壁面热流密度可由87W/m2激增到400W/m2，站厅气温可上升4.4℃。第三部分，进一步将理论研究成果服务工程实际，探讨了充分发挥地下车站壁面冷辐射作用、室外高温天下乘客在车站过渡区域热舒适性需求等要素，从而优化夏季空调季车站的运行气温和风速，可实现车站环控系统运营节能达24%左右。课题上述研究成果部分填补了地铁热环境相关领域的理论空白，具有创新性，为不同运营年限地铁区间隧道的温度调控和车站热环境的舒适节能运行提供了重要的理论依据和技术参考，具有重要的社会价值和工程意义。