摘要
由于载人航天器这一密闭狭小空间及其微重力这一特殊环境,舱内通风空调问题和热舒适环境与地面的HVAC问题不同,微重力效应特别是自然对流大为减弱影响着通风换热效果。本文首先分析了舱内通风空调问题的特殊性,通过无量纲分析和计算微重力的流体力学效应,然后利用FLUENT软件对两种集中通风方式进行数值模拟。模拟结果表明:微重力下几乎不存在“冷风下坠”或者“热羽”现象;集中斜进风在一定的进风角度和Re数下出现分岔解现象;与常重力相同通风条件下,微重力下自然对流的减弱使得舱内温度降低,换热减少,因此满足常重力热舒适要求的通风条件不一定满足微重力下热舒适性的要求。
Ventilation, air conditioning and thermal comfort environment of manned spacecraft＇s cabin is different to normal HVAC design due to its enclosed and limited space at microgravity. Microgravity effects especially weaken of natural convection affect the ventilation heat exchange. In this paper, the characteristics of cabin ventilation and air conditioning are analyzed and microgravity effects are calculated with dimensionless analysis. Then numerical simulation of two central ventilation styles is simulated by FLUENT software. It＇s concluded that the cold air drop and heat feather flow phenomena almost disappear. Bifurcation phenomenon of airflow is also found in oblique inlets of central ventilation at certain angle and Re number, and cabin temperature and heat exchange decrease due to weaken of natural convection at microgravity so that thermal comfort may be unsatisfied.
出处
《建筑热能通风空调》
2005年第4期86-90,共5页
Building Energy & Environment
