摘要 |
A method for thermally pumping volatile liquids and a pump for use therewith. The pump has an inlet liquid cooled pump chamber having therein a porous inlet membrane and a porous exit membrane defining between them a pump volume. The membranes are permeable to the liquid phase of the fluid being pumped but, when saturated with liquid, are not permeable to the vapor phase of the fluid. A passive check valve system permitting the passage of liquid but preventing the passage of vapor therethrough is thus formed by the membranes. A baffle plate with a heater located in a concavity therein is positioned in the pump volume adjacent the inlet membrane. The pump output is connected to the inlet of a suitable heat transfer system preferably of the heat-pipe type. With the pump filled with liquid, pumping is initiated by turning on the heater, forming a vapor bubble in the liquid in the pump volume. A heat input is continued until the vapor bubble has grown to a size sufficient to expel most of the liquid in the pump volume. The heating pulse is then terminated. Condensation of the vapor bubble then occurs and the resulting drop in pressure causes liquid to be drawn into the pump volume, setting the stage for the entire cycle to repeat.
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