Study on evaluation method for cross-ventilation environment taken account of steady ventilation flow rates and thermal comfort

进行了现场实验、风洞实验和图像分析。研究结果表明：(1)在满足一定条件的情况下，局部动力相似模型可以预测流量系数随风向和开口位置的变化。在这项研究中，进行了四种类型的风洞实验，以调查当该模型应用于入流开口时，这些要求必须满足的严格程度。当切向流的方向或剖面发生变化或洞口附近有墙体时，该模型的应用不存在实质性问题。(2)将局部动力相似模型与COMIS网络模型相耦合。对单区和双区建筑模型的风量预测精度进行了验证。与传统的孔板流动模型相比，耦合模型对流量系数和通风量的预测效果更好。(3)…出口气流特性2006年夏天，在一个交叉通风的房间里，用超声波风速计测量了更多的侧面和内部。交叉通风对能量谱的主要贡献出现在小于0.1 Hz的频率范围内，并且交叉通风的能量谱包含k-5/3指数衰减的波数区域。(4)当风速大于0.5m/S时，不同的风速变化和气流在时间和空间上的波动使受试者在交叉通风条件下比在空调系统气流条件下感觉更舒适。(5)在实验室内模拟了交叉通风和空调情况下风速波动对暖体模型表面温度波动的影响。为了弄清地表温度波动的频率，提出了一种将红外图像转换为功率谱图像的图像处理方法。(6)建筑覆盖率对通风性能的影响在屋顶上比在墙面上要小。屋顶窗被发现是一种非常有效的提高通风风量的工具，特别是在人口稠密的地区。较少

The field experiments, wind tunnel experiments and image analysis have been carried out. The findings of the study can be summarized as follows.(1) The local dynamic similarity model can predict discharge coefficients, which vary with wind direction and opening position, if some requirements are met. Four types of wind tunnel experiments were carried out in this study to investigate how strictly these requirements have to be met when the model is applied to inflow openings. There are no substantial problems in applying the model when the direction or profile of the tangential flow is changed or when there is a wall near the opening.(2) The local dynamic similarity model was coupled with a COMIS network model. The prediction accuracy of ventilation flow rates was verified for one-zone and two-zone building models. The coupled model achieved better predictions of discharge coefficients and ventilation flow rates than the conventional orifice flow model.(3) The airflow characteristics out … More side and inside a cross-ventilated room were measured by ultrasonic anemometers in summer 2006. The major contributions to the energy spectra of cross-ventilation are revealed in the frequency range less than 0.1Hz and that the energy spectra of cross-ventilation contain some region of wave numbers with an exponential decay of k-5/3.(4) When the air velocity was more than 0.5m/s, various air velocity changes and airflow fluctuations in time and space made subjects feel more comfortable under cross-ventilation than under airflows from the air-conditioning system.(5) The influence of air velocity fluctuations on surface temperature fluctuations of thermal mannequin was visualized in the experimental room under cross ventilated cases and under air conditioned cases. An image processing method to transfer the infrared animations to power spectrum images was proposed in order to clarify the frequency of surface temperature fluctuations.(6) The influence of building coverage ratio on ventilation performance was small rather on roofs than on walls. A roof window was found to be a very effective tool for increasing ventilation flow rates especially in densely populated area. Less