| 摘要 |
Air in an underground tube railway carriage is cooling with a soft ice slurry of water and glycol which was pumped from a fixed storage tank (8, fig 2) into a heat exchanger 17 that occupies substantially the whole length and width of the carriage roof. Alternatively if the carriage runs in the open air, it may have an on-board cooling system for replenishing the soft ice. The heat exchanger 17 has pipes 50-100mm in diameter that store cold; allow circulation; and transfer heat to the air with fans and fins. The slurry is circulated inside the heat exchanger 17 by pump 19. Controls mix the cooled air with recirculated air; counter passengers in zones of the carriage; and optically measure the refractive index of the soft ice. |
