Uncovering eco-friendly design in the ancient bronze goose-and-fish lamp: an unnoticeable gap boosts ventilation.
Jie XiaoQian ShenXiao Dong ChenPublished in: Proceedings of the National Academy of Sciences of the United States of America (2022)
The bronze goose-and-fish lamp exhibited in the national museum of China is a 2,000-y-old artifact once used for indoor lighting by nobility in the Western Han dynasty (206 BCE TO 25 CE). The beauty of this national treasure arises from its elegant shape vividly showing a goose catching fish with beautiful colors painted over the whole body. Beyond the artistic and historical value, what enchants people most is the eco-design concept of this oil-burning lamp. It is widely believed that the smoke generated by burning animal oil can flow into the goose belly through its long neck, then be absorbed by prefilled water in the belly, hence mitigating indoor air pollution. Although different mechanistic hypotheses such as natural convection and even the siphon effect have been proposed to qualitatively rationalize the above-claimed pollution mitigation function, due to the absence of a true scientific analysis, the definitive mechanism remains a mystery. By rigorous modeling of the nonisothermal fluid flow coupled with convection-diffusion of pollutant within and out of the lamp, we discover that it is the unnoticeable gap between goose body and lamp tray (i.e., an intrinsic feature of the multicompartmental design) that can offer definitive ventilation in the lamp. The ventilation is facilitated by natural convection due to oil burning. Adequate ventilation plays a key role in enabling pollution mitigation, as it allows pollutant to reach the goose belly, travel over and be absorbed by the water.
Keyphrases
- loop mediated isothermal amplification
- air pollution
- particulate matter
- respiratory failure
- heavy metals
- sensitive detection
- climate change
- mechanical ventilation
- fatty acid
- risk assessment
- health risk
- machine learning
- health risk assessment
- radiation therapy
- human health
- lung function
- magnetic resonance imaging
- computed tomography
- south africa
- locally advanced
- extracorporeal membrane oxygenation
- cystic fibrosis
- rectal cancer
- drinking water
- image quality