| 摘要 |
<p>A simple solar energy trap is assembled using two layers of flexible plastics film between which a heat transfer fluid (air) can circulate, one film being black and the other being transparent to visible light but opaque to infra red radiation. Suitable for covering e.g. freshly laid concrete, to apply extra warmth during the day and conserve local ground warmth at night. The two layers may comprise two plane sheets supported at different levels or a combination of a plane sheet and a corrugated sheet supported from a common level. The lower, dark layer may be of flexible foam instead of solid sheet. The path of the heat transfer fluid between the two layers may be controlled by a pattern of seams welded, stuck or stitched to join the two layers.</p> |
