| 摘要 |
PURPOSE:To prevent the increase of thermal resistance and the lowering of the capacity of the titled heat exchanger due to smudge by a method wherein small air bubbles are generated in a high temperature heat medium by making the heat medium run against a buffer plate or making the medium collapsed and the high temp. heat medium including such small air bubbles is circulated naturally or forcibly so that another heat medium having a low boiling point is boiled sufficiently by the high temperature heat medium even when the temperature of the latter is at moderately low level. CONSTITUTION:The high temperature heat medium A enters a preheater 1a from a high temperature heat medium inlet port 4 and the low boiling point heat medium B is injected from a multiholed nozzle 3b so that the two kinds of heat mediums come into direct contact with each other to exchange heat within the preheater 1a. In this case, the high temperature heat medium A operates as a continuous phase while the low boiling point heat medium B operates as a dispersing phase in the state of liquid drops and a heat exchange operation takes place due to heat conduction between the two heat mediums. In other words, the low boiling point heat medium B is boiled to vaporize within an evaporator 1b with the small air bubbles in the high temperature heat medium A acting as foaming nuclei and moves upward within the evaporator 1b in the form of a slag-like stream. Then the high temperature heat medium A which contains therein the vaporized low boiling point heat medium B runs against the buffle plate 6 arranged at the upper part of the outlet of the evaporator 1b so that the heat medium A is atomized and flows down to the lower part of a gas-liquid separator 2 as it swallows up the resultant small air bubbles and a greater part of the high temperature heat medium A flows out from the separator 2 through a recirculation pipe 7. |
