| 摘要 |
A heating and cooling system for a railway carriage 12 comprises a ceiling panel 10 made of extruded aluminium, running longitudinally of the carriage 12, and having it's exposed surface coated or treated to increase it's emissivity, with an array of ribs 14 on the upper side; an air conduit 18 conducting ambient or cooled air over the ribs 14; a ram air-intake (fig 2, 20) at one end of the roof (12) and an identically shaped air outlet (fig 2,22) at the other, so that the cooling air flow through the conduit is reversed on reversal of the carriage motion; control means to either permit or block the cooling air flow; and heating means in the form of an electric heating cable 16, passing through a passage formed in the ceiling panel 10 and being operated when the air flow is blocked, for the panel 10 to act as a heater. |
