NOVELTY - A hydrophilic evaporation groove comprises at least two-stage water holding groove, at least one-stage sleeve, a light collector, a heating pipe, a high reflecting coating, a tubular shell, a connecting pipe, a fresh water output pipe and a periphery device which is a vacuum pump. The hydrophilic evaporation groove further comprises groove (1), hydrophilic ceramic film (3), water wing (4), and water distributor (5). The water channel along the axial direction is distributed with water permeable holes (2).    USE - Hydrophilic evaporation groove for tubular solar sea water desalting device.    ADVANTAGE - The hydrophilic evaporation groove can improve solar seawater desalination and salt generation device using rate of the heat energy to improve the water production rate and the water outlet time of the system.    DETAILED DESCRIPTION - A hydrophilic evaporation groove comprises at least two stage water holding groove, at least one stage sleeve, light collector, heating pipe, high reflecting coating, tubular shell, connecting pipe, fresh water output pipe and periphery device which is a vacuum pump. The tubular shell is a tubular cylindrical vacuum shell. The tubular shell of the outer circle part is plated with a high reflection coating layer. In the tubular shell, the sink is gradually sleeved with a sleeve. The water sleeve or tubular shell which is not filled with seawater forms an evaporation condensation cavity, then sleeved with a containing groove in the most inner sleeve of the first level, in the first level holding water tank is sleeved with a heating pipe and the most of the first level of the water tank wall is provided with a light collector. Connecting pipe of each water level is connected with the tubular shell and inner wall of the sleeve is connected with the bottom and water output pipe. Water output pipe is connected with water tank. The channel containing water, sleeve and tubular shell are made of transparent plastic material. The hydrophilic evaporation groove comprises groove (1), hydrophilic ceramic film (3), water wing (4), and water distributor (5). In the first terminal containing water channel, two sides of the top edge of the upper step of the shell is cylindrical shell axial opening. The water channel along the axial direction is distributed with water permeable holes (2). The water channel is uniformly distributed at the outer surface provided with honeycomb holes. The outer surface containing groove is adhered with a layer of hydrophilic ceramic film. In the water tank, the outer surface of the side lower part symmetrical with the groove outer edge is welded with the arc-shaped water collecting wing tank. One end of the water wing is semi-sealed. The water tank is provided with a water collecting device. The water collecting device is provided with drain hole. The water wing is connected with the inner cavity of the water collecting device.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic sectional diagram of the hydrophilic evaporation groove.    Groove (1)    Water permeable holes (2)    Hydrophilic ceramic film (3)    Water wing (4)    Water distributor (5)