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。研究结果可以总结如下。(1)局部动力相似模型在满足一定要求的情况下，可以预测随风向和开口位置变化的流量系数。本研究中进行了四种类型的风洞实验，以研究当模型应用于入流开口时，这些要求必须严格到何种程度。当切向流动的方向或剖面发生改变或开口附近有壁面时，应用该模型没有实质性问题。(2)将局部动态相似度模型与COMIS网络模型相结合。对单分区和双分区建筑模型的通风流量预测精度进行了验证。与传统的孔板流动模型相比，该耦合模型对流量系数和通气流量的预测效果更好。(3) 2006年夏季，用超声波风速仪测量了交叉通风室内内外的气流特性。在小于0.1Hz的频率范围内对流能谱的贡献最大，且对流能谱中存在k-5/3指数衰减的波数区域。(4)当风速大于0.5m/s时，各种风速变化和气流的时空波动使受试者在交叉通风下比在空调系统气流下感觉更舒适。(5)在交叉通风情况下和空调情况下，可视化了空气流速波动对热人体模型表面温度波动的影响。为了明确地表温度波动的频率，提出了一种将红外动画转换为功率谱图像的图像处理方法。(6)建筑覆盖比对通风性能的影响较小，屋面影响较小，墙体影响较小。研究发现，屋顶窗户是增加通风率的有效工具，特别是在人口稠密的地区。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