低温热水地板辐射采暖室内颗粒物运动特性的模拟研究

发布时间：2019-06-04 21:00

【摘要】：低温热水地板辐射供暖系统作为一种逐渐得到广泛应用的采暖方式,具有节约能源的优势。但关于低温热水地板辐射采暖室内颗粒物运动特性方面的研究相对较少。影响室内颗粒物运动和扩散的主要因素有室内流场、颗粒物释放源位置和颗粒物的粒径等。因此本文将采用数值模拟方法,对低温热水地板辐射采暖室内流场和颗粒物运动特性进行研究和分析。本文建立了低温热水地板辐射采暖房间的物理模型。并选取了湍流模型、利用流体控制方程以及k-e方程,对低温热水地板辐射采暖室内的流场进行数值模拟,得到了室内温度场和速度场分布规律。结果表明:地面附近温度明显高于其他区域,而且地面附近温度分层现象明显。但室内整体温度分布均匀。基于Lagrangian方法建立颗粒相随机轨道模型,以1μm、2.5μm、5μm、10μm和20μm 5种粒径的颗粒物为例,对低温热水地板辐射采暖室内不同位置颗粒物释放源以及不同粒径颗粒物的运动特性进行数值模拟,得到了颗粒物浓度随时间和空间变化的分布规律。结果表明:(1)低温热水地板辐射采暖室内,颗粒物释放源位置对颗粒物浓度分布的影响比较明显。颗粒物释放源位于人员日常活动平面(Z=0.3 m)时,在呼吸平面颗粒物浓度相对较低,而颗粒污染物释放源位于发烟器平面(Z=1.5 m)和位于窗户平面处时,在成人呼吸高度上的颗粒物平均浓度都较高,会对人的呼吸作用产生影响。1(2)不同粒径颗粒物随时间和空间变化的差别很大。小粒径(d_p5μm)颗粒物对室内气流跟随性强,其运动是由热浮升力和室内气流的共同作用产生的。而大粒径(d_p10μm)颗粒物受重力作用的影响,大部分散布于房间下部区域或沉积到地面。本文对低温热水地板辐射采暖室内不同颗粒物释放源进行了较为全面的研究。分析了室内颗粒物在时间和空间上的变化特点。为后续低温热水地板辐射采暖室内颗粒物研究方面提供了参考。
[Abstract]:The low-temperature hot-water floor radiant heating system is a kind of heating mode which is widely used, and has the advantage of saving energy. However, that research on the characteristic of the particle motion in the radiant heating chamber of the low-temperature hot-water floor is relatively low. The main factors that affect the movement and diffusion of the particles in the room include the indoor flow field, the position of the particle release source and the particle size of the particulate matter. In this paper, the numerical simulation method is used to study and analyze the indoor flow field and the particle motion characteristics of the low-temperature hot-water floor radiant heating chamber. In this paper, the physical model of the radiant heating room of the low temperature hot water floor is established. The flow field in the low-temperature hot-water floor radiant heating chamber is numerically simulated by using the fluid control equation and the k-e equation, and the distribution law of the temperature field and velocity field in the room is obtained. The results show that the temperature in the vicinity of the ground is obviously higher than that of other areas, and the temperature stratification near the ground is obvious. But the indoor whole temperature distribution is uniform. The particle-phase random track model was established based on the Lagrangian method, and the particles of the particle size of 1. m u.m, 2.5. mu.m,5. mu.m,10. mu.m and 20. m The distribution of particulate matter concentration over time and space was obtained by numerical simulation of the particle release source and the movement characteristics of different particle size particles in the low-temperature hot-water floor radiant heating room. The results show that: (1) The influence of the position of the particle release source on the concentration distribution of the particulate matter is obvious in the low-temperature hot-water floor radiant heating room. When the particulate release source is located in the person's daily active plane (Z = 0.3m), the particulate matter concentration at the respiratory plane is relatively low and the particulate contaminant release source is located at the smoker's plane (Z = 1.5 m) and at the window plane, the average concentration of particulate matter on the adult respiratory height is high, The effect of different particle size particles on the change of time and space is very large. The small particle size (d _ p5. mu.m) particulate matter is strong in the indoor air flow, and its motion is produced by the co-action of the heat floating force and the indoor air flow. While the large particle size (d _ p10. mu.m) particles are affected by the effect of gravity, most of which are dispersed in the lower part of the room or deposited on the ground. In this paper, the release of different particulate matter in the radiant heating room of the low-temperature hot-water floor is studied in a more comprehensive way. The characteristics of indoor particulate matter in time and space were analyzed. And provides a reference for subsequent low-temperature hot-water floor radiation heating indoor particle research.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU832.16

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