Measuring the air infiltration rate in buildings is essential for reducing energy use and improving indoor air quality. This rate has traditionally been determined by means of the blower door method, which is disruptive to building occupants, cannot identify the location of infiltration, cannot provide the infiltration rate for a section of the envelope, and requires considerable effort for setup and tear-down. Therefore, this study has developed a novel technique to measure air infiltration in buildings using an infrared camera. A thermographic image of a building envelope produced by an infrared camera and the measured indoor/outdoor air parameters (velocity, temperature, and pressure) were used to identify the effective crack size and air infiltration rate by means of theoretical heat transfer and fluid mechanics analyses. The proposed method was validated by experimental measurements in an environmental chamber and an office. The experiment in the environmental chamber constructed a small-scale room with known crack size. The experimental setup was comparable to actual conditions. The proposed method was able to predict the crack size within a relative error of 20%. For the experiment in the office, this study used the tracer-gas decay method to measure the air infiltration rate, and the relative error of the calculated air infiltration rate was only 3%.

测量建筑物中的空气渗透率对于减少能耗和改善室内空气质量至关重要。传统上，该速率是通过鼓风门方法确定的，该方法会破坏建筑物的居住者，无法确定渗透的位置，无法提供一部分信封的渗透率，并且需要花费大量的精力进行设置和拆除。因此，这项研究开发了一种新颖的技术，可以使用红外热像仪来测量建筑物中的空气渗透情况。通过理论传热和流体力学分析，使用红外热像仪生成的建筑物围护结构的热像图和测得的室内/室外空气参数（速度，温度和压力）来确定有效的裂缝尺寸和空气渗透率。通过在环境室和办公室进行的实验测量验证了所提出的方法。在环境室中进行的实验建造了一个具有已知裂缝尺寸的小房间。实验设置与实际条件相当。所提出的方法能够在20％的相对误差内预测裂纹尺寸。对于办公室中的实验，本研究使用示踪气体衰减法测量空气渗透率，计算出的空气渗透率的相对误差仅为3％。所提出的方法能够在20％的相对误差内预测裂纹尺寸。对于办公室中的实验，本研究使用示踪气体衰减法测量空气渗透率，计算出的空气渗透率的相对误差仅为3％。所提出的方法能够在20％的相对误差内预测裂纹尺寸。对于办公室中的实验，本研究使用示踪气体衰减法测量空气渗透率，计算出的空气渗透率的相对误差仅为3％。