Central circulation tube evaporator This evaporator is also called a standard evaporator. Its heating chamber is composed of vertical tube bundles, with a central circulation tube with a large diameter in the middle, and other heating tubes with smaller diameters are called boiling tubes.
Because the central circulation tube is larger, the heat transfer surface occupied by the unit volume of the solution is smaller than the unit solution in the boiling tube, that is, the solution in the central circulation tube and other heating tubes are heated to different degrees, so the density of the vapor-liquid mixture in the boiling tube The density of the solution in the central circulation pipe is lower than that in the central circulation pipe, and the upward suction effect of the rising steam will cause the solution in the evaporator to form a circulating flow that descends from the central circulation pipe and rises from the boiling pipe.
This kind of circulation is mainly caused by the density difference of the solution, so it is called natural circulation. This effect is beneficial to the improvement of the heat transfer effect in the evaporator.
