透明混凝土围护结构光热耦合传递机理与气候响应特性研究

Translucent concrete has been widely receiving attentions and applications because of its good lighting transmission and architectural expressiveness, but its internal complex optical-thermal transfer characteristics have not been well understood. In addition, no research has been done on the systematic theoretical and experimental studies to explore the climate response characteristics of translucent concrete. In this project, the mechanism of optical-thermal coupling transmission and the climate response characteristics of the translucent concrete are studied. A theoretical model, numerical analysis and experimental method for the analysis of translucent concrete are proposed. Based on the Fermat's shortest optical path principle and the Boltzmann transport equation, an optical fiber radiation transfer model is established. The embedded optical fibers are abstracted into finite line heat sources. The Green's function method, the virtual heat source method and the Duhamel theorem are used to describe the heat transfer of the concrete. Taking the interaction between radiation field in optical fiber and temperature field in concrete into consideration, the optical fiber radiation transfer process, self-heating process in fiber and heat transfer process in concrete are coupled together to establish the coupled optical-thermal transfer model of translucent concrete. The model is further simplified to reduce the computational cost. The experimental platform of translucent concrete is to be built for the model and numerical algorithm verification. The energy consumption characteristics and lighting characteristics of translucent concrete in different climates are simulated and analyzed, and the structural parameters of translucent concrete are optimized, laying a scientific foundation and theoretical basis for the engineering application of translucent concrete.

透明混凝土因其良好的透光性和建筑表现力受到广泛关注和应用，但其内部复杂的光热传递特性并未被很好的理解，更未有完整的理论和实验研究来探索其气候响应特性。本项目开展透明混凝土光热耦合传递机理与气候响应特性研究，建立一套分析透明混凝土的理论模型、数值分析和实验方法。基于费马最短光程原理以及玻尔兹曼输运方程，建立光纤辐射传递模型；将内嵌光纤抽象成有限长线热源，采用格林函数法、虚拟热源法以及杜哈梅尔定理描述混凝土传热过程，综合考虑光纤辐射场与混凝土温度场的相互作用机理，将光纤辐射传递过程、光纤自发热过程和混凝土传热过程耦合起来，建立透明混凝土光热耦合传递模型，简化模型，减少计算量；搭建透明混凝土实验平台，验证模型和数值方法。模拟分析不同气候下透明混凝土的能耗特征和采光特性，优化透明混凝土的结构参数，为透明混凝土的工程应用奠定科学基础和理论依据。

透明混凝土凭借其良好的透光性以及独特的装饰效果，被认为别具魅力且应用前景光明，为建筑围护结构兼顾自然采光与建筑节能提供了新思路，但其内部复杂的光热传递特性并未被很好地理解，更未有完整的理论和实验研究来探索其气候响应特性。.本项目遵循申请书所设计的建立模型-实验验证-应用分析的技术路线，结合理论分析、数值模拟与实验研究方法，对透明混凝土建筑围护结构在不同气候条件下的自然采光性能和节能潜力进行优化，分析了透明混凝土建筑围护结构的气候适应性。.首先，采用射线追踪法建立透明混凝土建筑围护结构的辐射传递模型，分析了光纤数值孔径、光纤体积比以及光纤长度等参数对透明混凝土自然采光性能的影响，通过研究代表城市的应用情况总结了透明混凝土自然采光最佳壁面倾角与当地纬度关系的经验公式。.其次，分析了透明混凝土的非稳态传热特性，建立并实验验证了透明混凝土建筑围护结构光热耦合模型，研究得到了透明混凝土建筑围护结构太阳得热能力随太阳入射角变化的变化规律，并提出了优化透明混凝土节能潜力的方法。.最后，提出了一种将光纤以一定倾角嵌入到混凝土的新型光纤倾斜式透明混凝土建筑围护结构，为提高透明混凝土的自然采光性能以及节能潜力提供了一种新思路，发展了相对应的透明混凝土光热耦合传递模型，优化了光纤倾角和光纤数值孔径等参数以改善其气候适应性。.本项目发展了一套能够正确描述透明混凝土建筑围护结构光热特性的理论模型和数值分析方法，总结了透明混凝土围护结构的气候适应性，圆满地完成了既定研究目标，相关成果为透明混凝土建筑围护结构的设计与应用提供了理论基础与指导。