The invention discloses a nano-coating for an unsaturated evaporation heat transfer surface. An anti-corrosion layer and a hydrophilic layer can be coated on the heat transfer surface in sequence; a heat transfer layer can be coated between the anti-corrosion layer and the hydrophilic layer; the coated heat transfer surface is irradiated with ultraviolet light for one hour, so that a contact angle between a coated surface and a water film is reduced to 0-5 degrees; the coating thickness of the anti-corrosive layer is 2-15 nanometers; the coating thickness of the hydrophilic layer is 8-35 nanometers; and ultraviolet light is used for irradiating intermittently every 2-3 days, so that the hydrophilicity of the coated surface is kept. The material characteristic of a heat exchange surface is improved, so that a spreading area on the heat transfer surface under the unit water amount of the water film is increased, distribution is more uniform, the phenomenon of 'dry spot' is avoided effectively, the scaling phenomenon of the heat transfer surface is delayed, heat and mass transfer coefficients between water and air are increased, and heat exchange performance is enhanced.

Dongsheng Zhu

Papers

Nano-coating for unsaturated evaporation heat transfer surface