FALLING FILM EVAPORATOR

摘要

Disclosed is a falling film evaporator, comprising a cylinder body (1), wherein an upper distributor (3) is provided at the upper part inside the cylinder body (1), both sides of the top part of the upper distributor (3) are respectively provided with an air baffle plate (4), an edge of the air baffle plate (4) on at least one side is provided with a sawtooth part (5), the sawtooth part (5) and an inner wall of the cylinder body (1) enclose an air passage which is in communication with a gas refrigerant exit, bottom ends of two side walls of the upper distributor (3) are respectively provided with a spoiler plate (6), an upper heat exchange pipe group (7) is provided below the upper distributor (3), a lower heat exchange pipe group (8) is provided below the upper heat exchange pipe group (7), an oil-rich zone (9) is below the lower heat exchange pipe group (8), a liquid level sensor (10) is provided for the oil-rich zone (9), a signal output end of the liquid level sensor (10) is connected to a signal input end of a throttling device, and an oil return opening (11) is provided in the oil-rich zone (9). The falling film evaporator is switchable between a full falling film heat exchange mode and a mixed falling film heat exchange mode, avoiding the problem of insufficient dripping and leaching of the heat exchanging refrigerant at the bottom or an excessive amount of refrigerant being charged, and at the same time avoiding the phenomenon of liquid entrainment during gas suction so as to increase the heat transfer coefficient and heat exchange efficiency.