Research On Heat Exchanger Anti-fouling Characteristics Of Heat Exchanger Tube With Helical Spring Insert

Heat exchanger was a pivotal equipment in the thermal process,and a necessaryequipment for using and saving energy.As the oil crisis was becoming more and moreserious,energy shortage had become the main factors which restrict the development of theeconomy,so heat transfer enhancement technology had got rapid development.But as theuniversal existence of fouling in heat exchanger,it would extreme affect the heat transferefficiency,and cause extreme energy waste and economic losses,even sometimes make heatexchanger lose its heat exchange function.Therefore,it was important practical significanceto research on anti-fouling of heat exchanger.Helical spring,as an usual interpolation content,it can increase the exchangecoefficient and has an online cleaning fouling ability,but the increase of fluid flowresistance is not big through the elastic vibration and the fluid disturbance of interpolationcontent.An experimental research on the fouling characteristics of heat exchange tube withhelical spring insert was carried out in this paper.The main contents are generalized asfollows:The fouling experimental platform was established.the fouling experiment of plaintube and tube with helical spring insert were done.Through artificial CaCO3solution as thecommon fouling of heat exchanger.Fouling resistance method was used to deal with theexperimental data.The relationship of induction period and fouling resistance changes withtime were got,and the anti-fouling characteristics and resistance performance of plain tubeand tube with helical spring insert were compared.Then,the effects of water hardness,bathtemperature,flow rate and helical spring’s pitch,wire diameter,outer diameter in foulingprocess were researched.The results show that the fouling rate and the fouling thermalresistance increase,and the fouling induction period decrease with increased waterhardness,but when water hardness get to a limitation,the fouling thermal resistance begin todecrease.As the temperature rise,the induction period tend to disappear,the fouling rate will increase and the fouling thermal resistance will relevantly increase.When speeding upof water flow,the induction period increase,the fouling thermal resistance and fouling ratereduce at the same time.With the comparison between plain tube and tube with helicalspring insert,it indicates that the tube with helical spring insert has a good anti-foulingperformance.With the decreasing of helical spring’pitch,the increasing of helical springwire diameter,the increasing of helical spring outer diameter,the heat exchanger tube withhelical spring insert has showed a better anti-fouling characteristics,but because of the useof helical spring,the fluid flow resistance would increase.