Department of Mechanical Engineering, Konkuk University, Seoul, Republic of Korea.
Department of Otorhinolaryngology: Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea.
J Therm Biol. 2019 Jul;83:60-68. doi: 10.1016/j.jtherbio.2019.05.004. Epub 2019 May 13.
The air-conditioning characteristics in nasal cavity models obtained from two subjects exhibiting different degrees of the nasal cycle states in terms of the airflow partition were investigated using computational fluid dynamics. A constant inspiratory flow rate of approximately 250 mL/s was considered, and the air temperature and relative humidity at the inlet were assumed to be 25 °C and 35%, respectively. The air-conditioning capacities of the congested and decongested sides were assessed by the amounts of epithelial heat and water vapor transferred to the inhaled air through the airway from the nostrils to the end of the septum. The results revealed that the air temperature and relative humidity near the end of the septum, respectively, reached approximately 31.4-32.5 °C and 81.4-88.0% in the decongested sides and 34.0-35.9 °C and 95.3-100% in the congested sides. The differences seen in the air temperatures and relative humidity between the congested and decongested sides were found to be larger in the cavity model that showed a larger degree of reciprocal change in the airflow rate. From a fluid mechanics perspective, while the congested side is in a rest period during the nasal cycle such that a lower amount of airflow is transported through it, this side, in effect, works to provide assistive air-conditioning capacity to the nasal cavity and aids when insufficiently conditioned airflow passes through the decongested side so that the inhaled air merging after the septum can approach the alveolar condition favorably through the nasopharynx.
使用计算流体动力学研究了在鼻腔周期状态方面表现出不同程度的气流分配的两个受试者的鼻腔模型中的空调特性。考虑了约 250 毫升/秒的恒定吸气流量，并且入口处的空气温度和相对湿度分别假定为 25°C 和 35%。通过从鼻孔到鼻中隔末端的气道向吸入空气中传递的上皮热量和水蒸气量来评估充血侧和非充血侧的空调能力。结果表明，在鼻中隔末端附近的空气温度和相对湿度分别在非充血侧达到约 31.4-32.5°C 和 81.4-88.0%，在充血侧达到 34.0-35.9°C 和 95.3-100%。在显示气流速率更大的往复变化程度的腔模型中，发现充血侧和非充血侧之间的空气温度和相对湿度差异更大。从流体力学的角度来看，虽然在鼻腔周期中充血侧处于休息状态，从而通过其输送的空气流量较低，但该侧实际上为鼻腔提供辅助空调能力，并在不足的条件下空气流量通过非充血侧时提供帮助，从而使合并后的吸入空气可以通过鼻咽部有利地接近肺泡条件。
