| 摘要 |
<p>The heat-pump installation operates all the year round, extracting heat from freezing water in water as efficiently as from warm water in summer. It copes with the period when ice crystals are beginning to form in liquid waters by discouraging their formation close to the evaporator: (a) by covering it in a suitable sheathing material, (b) by keeping the temp. at the evaporator surface high enough for the ice crystals to form elsewhere and (c) by pulsed pumping of the refrigerant to produce temp. fluctuations at the evaporator. To cope with such ice as does form, the evaporator's smooth surface is divided into small areas by a criss-cross of heat-insulating ribs, so that ice comes off easily in small flakes. The warmth contained in the refrigerant is used for the de-icing.</p> |
