相变储能地板辐射供暖系统蓄热性能数值模拟

摘要

Taking the problem of thermal environment control inside building with phase change material (PCM)floorboards as the background of the research,simulates the two-dimensional square cavity model with low-temperature radiation floor heating system using Fluent software,considers the variable property calculation and the coupled heat transfer process consists of solid-liquid phase change,heat conduction,natural convection and radiation in this physical model.Investigates the influence of phase change temperature and thermal conductivity of PCM on the air temperature in the cavity respectively.The results show that improving the thermal conductivity of PCM can reduce thermal inertia of the heating system,and accelerate the temperature rising in the cavity per hour.Obtains the relationship expression between phase change temperature and the air temperature in the cavity.Presents a new floor heat storage structure to increase the air temperature in the cavity, which provides a diverse energy utilization.%以加装相变储热地板的建筑热环境控制为背景，采用 Fluent 软件对底部加装相变材料的低温热水辐射供暖二维方腔模型进行了数值模拟，该模型考虑变物性计算，并包含相变区及导热、固体壁面间辐射与自然对流的耦合换热。研究了相变材料的相变温度和导热系数对方腔内空气温度的影响。研究结果表明，提高相变材料的导热系数可使供暖系统的热惰性减弱，即加快单位时间方腔内空气的温升。拟合出了相变温度与方腔内空气温度的关系式。提出了一种新型地板蓄热结构，可加快方腔内空气温升，还可实现能源利用多元化。