烧结型多孔表面管外池沸腾传热特性  

Pool boiling heat transfer on sintered porous coating tubes

作　　者：郭兆阳[1] 徐鹏[1] 王元华[1] 徐宏[1] 曾宪泰[1] 杨胜[1] 

机构地区：[1]华东理工大学机械与动力工程学院,化学工程联合国家重点实验室,上海200237

出　　处：《化工学报》2012年第12期3798-3804,共7页CIESC Journal

基　　金：中国博士后基金项目(201104244);上海市自然科学基金项目(10ZR1408100)~~

摘　　要：实验研究了热通量为0.1～160kW.m-2时,去离子水在光管及烧结型多孔表面管管外的池沸腾传热特性,分析了换热管布置方式(垂直与水平)、管径大小(20、25和32mm)与多孔层颗粒尺寸(30～105μm)对池沸腾传热特性的影响规律。结果表明:去离子水在多孔管表面的起始沸腾过热度小于光管,比光管低3K左右;多孔表面管可明显强化核态沸腾传热,其沸腾传热系数可达光管的3～4.5倍;大热通量下,换热管水平布置时的传热效果较垂直布置佳,且布置方式对多孔管换热效果的影响比对光管的影响小;随管径增大,光管与多孔表面管的沸腾传热系数降低;大颗粒尺寸多孔层的强化效果优于小颗粒尺寸多孔层。This paper presents an experimental investigation on nucleate pool boiling of saturated deionized water from uncoated and self-made sintered coated porous tubes with the heat flux from 0.1 to 160 kW·m-2.The influences of the orientation（vertical and horizontal）and diameter（20,25 and 32 mm）of the heating tube and the coating particle size（between 30 and 105 μm）on the nucleate pool boiling were investigated.The results show that the sintered porous coatings can lower the incipient boiling superheat and enhance nucleate boiling heat transfer coefficient compared with smooth surfaces.The incipient boiling superheat of deionized water drops from 4—5 K with the smooth tubes to 1—2.5 K with the porous coated tubes.And the nucleate heat transfer coefficient on porous coating tubes are 3—4.5 times those of smooth tubes.It is found that,at high heat flux,the horizontal tube presents better boiling performance than the vertical tube due to the decrease in bubble slug formation on the tube surface and easy access of liquid to the surface.In addition,the influence of tube orientation on boiling performance is smaller for the porous tube than for smooth tubes.The heat transfer coefficients on smooth tubes and porous tubes decrease as the tube diameter increases.The data for different porous coatings suggest that small particle has slight effect on boiling heat transfer and greater enhancement is found with larger particle size.

关 键 词：烧结多孔表面 核态沸腾 起始沸腾过热度 强化传热 

分 类 号：TK124[动力工程及工程热物理—工程热物理]