Experimental Study On The Performance Of Wetting Pad Of Direct Evaporation Cooling Air Conditioner

This paper in the light of problems of wetted pads in direct evaporating coolingair-conditioners，such as microbial producing, moldy smell Issuing, use modifiedTiO₂photocatalysis material compound powders to improve DEC air conditioner’swetted pads’ surface performance, in order to broaden the operation place of this typeair-conditioner.This paper utilizes the characteristics of rare earth elements, natural electricpolarity and radiation infrared performance of tourmaline and the photocatalyticperformance of TiO₂. First, the TiO₂/Ce（NO3）3composite powders including mineraltourmaline powders were prepared,and their preparation technology and structurewere studied, we also discussed how tourmaline enhanced TiO’2photocatalysis. Thenwe discussed the bacteria-killing performance of the composite powders throughexperience. Finally, the composite powders were made as film on the special paper,witch worked as the DEC air-conditioner’wetted pad, and tested the film’sbacteria-killing performance through experience. The main research conclusions areas follows:（1）The TiO₂/Ce（NO3）3composite powders including mineral tourmalinepowders were prepared, the powders were characterized by X-ray diffraction （XRD）and scanning electron microscopy （SEM）, and their UV-Vis spectroscopy weremeasured by Uv spectrophotometer. The results showed that the clusters of TiO₂particles with lots of nano-sized TiO₂particles on the surface and ladder layerstructures, were grown on the surface of fine tourmaline powders; the absorbancy ofthe sample deferred with different additive amount of tourmaline powders, theappropriate tourmaline powders can enrich the absorbancy and enlarge the spectralresponse range.（2）Discussed the bacteria-killing performance of the composite powdersthrough experience（took aspergillus and golden staphylococcus for example）. Theresults showed that composite powders’ bacteria-killing capacity was much betterthan pure TiO₂,their bacteria-killing capacity enhanced with the dosage and the contact time with the bacteria.（3）The composite powders were made as film on the special paper, witchworked as the DEC air-conditioner’wetted pad, the films were characterized by AFM.Then we tested the film’s bacteria-killing performance and hydrophilic throughexperience, the result showed that the film had certain bactericidal.