检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:李冠球[1] 李蔚[1] 张政江[1] 张巍[1] 徐志明[2]
机构地区:[1]浙江大学机械与能源工程学院,浙江杭州310027 [2]东北电力大学研究生部,吉林吉林132012
出 处:《浙江大学学报(工学版)》2010年第3期494-498,600,共6页Journal of Zhejiang University:Engineering Science
基 金:国家"973"重点研究发展计划资助项目2007CB206904);国家自然科学基金资助项目(50976096);国家"863"高技术研究发展计划资助项目(2007AA05Z226);浙江省钱江技术研究资助项目(2008R10026)
摘 要:研究了5根内径为15.54mm的铜质内置螺纹管的污垢数据,并给出了在雷诺数为16000,污垢质量浓度为1300g/m3下的加速颗粒结垢实验数据.螺纹的几何参数采用目前应用于冷凝器的商用强化管中较为典型的一组几何参数:螺纹数为10~45、螺纹角为25°~45°、螺纹高为0.33~0.55mm;实验用的氧化铝颗粒平均直径为3μm.通过冯-卡门类比计算质量传递系数,壁面剪切应力则由压降数据来获得.据此,建立了一个半理论化的模型,讨论并得到了污垢热阻比与螺纹管几何参数、效率指数的一系列关系式,这些关系式以及对污垢的理论分析方法可应用于预测冷却水系统中螺纹管的污垢形成.The accelerated particulate fouling data were provided in five 15.54 mm I.D. copper,helically ribbed tubes taken at the condition of Re=16 000 and 1 300 g/m3 concentration. The geometries of the helical-rib tubes provide a class of internal enhancement that is typical of commercially enhanced tubes presently used in water chillers,and the ranges of geometric parameters are number of rib starts (10 to 45),helix angle (25° to 45°),and helix height (0.33 to 0.55 mm). Aluminum oxide particles with 3.0 μm average particle diameter were used as foulant in the experiment. The mass transfer coefficient was obtained by using the Von-Karman analogy and the wall shear stress was obtained from pressure drop data. Based on the above two approaches,a semi-theoretical model was developed to investigate the effects of geometric parameters and efficient indexes on the fouling characteristics in the enhanced heat transfer tubes. The correlations and the analyses can be used directly to assess the fouling potential of helically-rib in cooling water systems.
分 类 号:TK124[动力工程及工程热物理—工程热物理]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.74