工程热物理学报
工程熱物理學報
공정열물이학보
JOURNAL OF ENGINEERING THERMOPHYSICS
2009年
9期
1578-1580
,共3页
李蔚%张巍%李冠球%张政江%秦新安%王铁坤%徐志明
李蔚%張巍%李冠毬%張政江%秦新安%王鐵坤%徐誌明
리위%장외%리관구%장정강%진신안%왕철곤%서지명
污垢热阻%普朗特类比%强化传热
汙垢熱阻%普朗特類比%彊化傳熱
오구열조%보랑특류비%강화전열
fouling resistance%Prandtle analogy%enhanced heat transfer
本文对一冷却塔中的7根螺纹管进行了长时间污垢实验研究.螺纹管几何参数范围:螺纹数18~45,螺纹角25°~45°,螺纹高0.33~0.55 mm.污垢是颗粒污垢和析晶污垢的混合物.本文基于普朗特类比,引入修正因子β(β=(A_w/A_(wp))/(A_c/A_(cp)),A_w为润湿面积,A_c为截面积,下标p表示光管),对半经验污垢预测模型进行修正,证明了螺纹管内参数对污垢热阻的形成影响很大,并建立了不同结构参数的螺纹管的统一结垢模型,对工程实际有一定指导意义.
本文對一冷卻塔中的7根螺紋管進行瞭長時間汙垢實驗研究.螺紋管幾何參數範圍:螺紋數18~45,螺紋角25°~45°,螺紋高0.33~0.55 mm.汙垢是顆粒汙垢和析晶汙垢的混閤物.本文基于普朗特類比,引入脩正因子β(β=(A_w/A_(wp))/(A_c/A_(cp)),A_w為潤濕麵積,A_c為截麵積,下標p錶示光管),對半經驗汙垢預測模型進行脩正,證明瞭螺紋管內參數對汙垢熱阻的形成影響很大,併建立瞭不同結構參數的螺紋管的統一結垢模型,對工程實際有一定指導意義.
본문대일냉각탑중적7근라문관진행료장시간오구실험연구.라문관궤하삼수범위:라문수18~45,라문각25°~45°,라문고0.33~0.55 mm.오구시과립오구화석정오구적혼합물.본문기우보랑특류비,인입수정인자β(β=(A_w/A_(wp))/(A_c/A_(cp)),A_w위윤습면적,A_c위절면적,하표p표시광관),대반경험오구예측모형진행수정,증명료라문관내삼수대오구열조적형성영향흔대,병건립료불동결구삼수적라문관적통일결구모형,대공정실제유일정지도의의.
The experiments on fouling resistant of the seven different helical-rib tubes in cooling tower have been carried by US for a long time.The ranges of geometric parameters were number of rib starts(18~45),helix angle(25~45 deg.),and height(0.33~0.55 mm).The fouling mechanism is a combination of precipitation fouling and particulate fouling.Based on the Prandtle analogy,β factor (β=(A_w/A_(wp))/(A_c/A_(cp)),A_w is the wetted area,A_c is the cross section area,and the subscript p means the plain tube) was introduced to revise the semi-theoretical fouling model.The geometric parameters were proved to affect the fouling growing strongly.A new unified theoretical fouling correlation has been developed for all the tubes.The new correlation can be directly used to assess the fouling potential of enhanced tubes in actual cooling water situations.