CAJ | 학술논문

采用Ni-P-PTFE化学复合镀对铜管进行表面处理能有效减少污垢在换热表面上形成.然而,在实际应用上,复合镀层对铜管导热性能的影响是必须考虑的问题.实验利用热阻法对铜基Ni-P-PTFE复合镀层的导热系数进行测量,并利用Wilson plot方法处理数据最终得到Ni-P-PTFE复合镀层的导热系数.分析了镀层各组分镍(Ni),聚四氟乙烯(PTFE),碳(C),磷(P)的质量分数对其导热性能的影响规律.结果表明,Ni-P-PTFE复合镀层的导热系数随PTFE和P的质量分数增大而降低,随C的质量分数增加而增大.当PTFE,C以及P的质量分数w(PTFE)=1.76%,w(C)=3.82%和w(P)=10.81%时,最大值为23.12 W/(m.K).尽管复合镀层的导热系数不高,但由于其厚度很小,镀层产生的热阻仅为9.91×10-5~1.6×10-4(m2.K)/W,所以复合镀层铜管仍保持很高的导热系数值314.88~357.55W/(m.K).
채용Ni-P-PTFE화학복합도대동관진행표면처리능유효감소오구재환열표면상형성.연이,재실제응용상,복합도층대동관도열성능적영향시필수고필적문제.실험이용열조법대동기Ni-P-PTFE복합도층적도열계수진행측량,병이용Wilson plot방법처리수거최종득도Ni-P-PTFE복합도층적도열계수.분석료도층각조분얼(Ni),취사불을희(PTFE),탄(C),린(P)적질량분수대기도열성능적영향규률.결과표명,Ni-P-PTFE복합도층적도열계수수PTFE화P적질량분수증대이강저,수C적질량분수증가이증대.당PTFE,C이급P적질량분수w(PTFE)=1.76%,w(C)=3.82%화w(P)=10.81%시,최대치위23.12 W/(m.K).진관복합도층적도열계수불고,단유우기후도흔소,도층산생적열조부위9.91×10-5~1.6×10-4(m2.K)/W,소이복합도층동관잉보지흔고적도열계수치314.88~357.55W/(m.K).
Copper tubes covered by Ni-P-PTFE composite coating can mitigate fouling adhesion on the heat exchange surface. However, the impact of composite coating on the thermal conduction of copper tubes should be considered. A thermal resistance method was utilized to measure the heat transfer coefficient of copper tubes with Ni-P-PTFE composite coatings. The thermal conductivities of these Ni-P-PTFE composite coatings were gained by means of Wilson plot in the end. The effects of Ni, PTFE, C and P contents were discussed on the thermal conductivity of Ni-P-PTFE composite coating. The results showed the thermal conductivity of these Ni-P-PTFE composite coatings were weakened by the increases of PTFE and P contents, but enhanced when the C content increased. It reached a peak value 23.12 W/(m.K) when w(PTFE)=1.76%, w(C)=3.82% and w(P)=10.81%, respectively. Although the thermal conductivities of the composite coatings were lower, their thermal resistances in the total heat transfer process were from 9.91×10-5 to 1.6×10-4(m2.K)/W due to their small thickness. Therefore, the tubes with Ni-P-PTFE composite coatings still kept high thermal conductivities 314.88~357.55W/(m.K).