文档介绍：摘要摘要随着国家能源结构的调整和能源环保政策的不断加大,冷凝式燃气热水器作为高效低污染设备具有广阔的应用前景。冷凝换热设备的关键技术是热交换器的腐蚀防护和烟气对流凝结传热传质的强化。本课题针对冷凝式燃气热水器的高低温热交换器的腐蚀,研究了腐蚀发生的机理、影响因素及常用的防腐措施。根据热交换器的复杂结构、冷凝式热交换器的冷凝换热特点,以及铜的优良传热与加工性能,本课题采用在换热器表面涂防腐蚀涂料的方法来降低腐蚀危害,并通过酸性盐雾试验、酸溶液浸泡试验、附着力、硬度试验等对常用的几十种涂料进行初期筛选。然后对冷凝式燃气热水器的热交换器进行耐久性试验,对比5种涂料的防腐性能、耐久性能、传热性能、燃烧性能等在耐久性试验前后的变化,选取最佳的涂层材料。通过分析耐久性试验结果,本课题采用有机硅铝粉作高温段热交换器涂料,环氧酚醛作低温热交换器涂料。燃气壁挂炉是燃气热水器的功能推广,本课题分析了其优缺点,对其在市场前景及所遇到的问题进行了初期评价,并指出冷凝式燃气壁挂炉是其发展方向。最后,本课题用CFD专业软件对肋片式换热器的换热、流动特性进行数值模拟,研究肋片间距、烟气流速、排烟温度、排列方式等因素对流动、换热的影响。关键词:冷凝式燃气热水器,防腐蚀,涂层,数值模拟 ABSTRACT ABSTRACT With theadjustment on energy structure and theenhancement on environment protection,the condensing gas heat water,which ishi曲efficient and low contaminative,has a prospect ofwide key technologies ofthe equipments forfluegas condensing are anticorrosion ofheatexchanger and heat transferenhancement inconvection andcondensation offluegas. Focusing on thesensible-latent heatexchanger of thecondensing gas water heater,this dissertation COVerS themechanism and influence factorsofthecorrosion, common anticorrosion measures,and plicated structure of heatexchanger,the characteristicofcondensation,as wellas theexcellent capabilities ofheat exchanger and easilyprocessing ofcopperfinned-tube,anticorrosioncoating isselected to reduce the hartn the saltspray test,acidic immersion test,adhesive attraction testand hardness test,fivecoating materialsare picked up from dozens mon anticorrosioncoating the durabilitytest,the bestcoating materials forcondensing gaswater heaterisselected bycontracting thechanges ofanticorrosion,durability,heat-transfer bustion test resultsshow thataluminum silicone heat-resistantcoating and the epoxy phenolphthalein coating ale suitable forthesensible heatexchanger and the latent heatexchanger respectively. Astheprevalence ofthe gas heatwater,thewall—mounted boiler isalsostudied. ne ing,as well asthemarket prospect ofgas wall—moun