化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
12期
4709-4715
,共7页
祝杰%吴振元%叶世超%刘振华%杨云峰%白洁
祝傑%吳振元%葉世超%劉振華%楊雲峰%白潔
축걸%오진원%협세초%류진화%양운봉%백길
喷淋塔%碰撞%液滴%Sauter平均直径%分布
噴淋塔%踫撞%液滴%Sauter平均直徑%分佈
분림탑%팽당%액적%Sauter평균직경%분포
spray tower%collision%droplet%Sauter mean diameter%distributions
以水和空气为实验介质,通过拍照法获得喷淋塔内液滴粒径分布,考察了不同喷淋量及空塔气速对塔内不同高度处液滴Sauter平均直径(SMD)的影响,并对液滴粒径分布进行了理论分析。结果表明,喷淋塔顶部液滴分布密集,底部稀疏,液滴群在下落过程中,平均粒径减小且趋于均匀化;塔顶处液滴 SMD 随喷淋量的增加而增大,处在塔中下部的液滴 SMD 则随喷淋量增大而减小,提高空塔气速,可减小平均粒径;理论分析认为,液滴粒径减小主要是由于发生了碰撞破碎的缘故,而塔内液滴大小不一是碰撞的主要原因;通过量纲1化拟合得到喷淋塔内液滴 SMD 经验关联式,其计算结果与实验值吻合较好;考虑液滴破碎的喷淋塔比表面积比不考虑破碎的比表面积大70%左右。
以水和空氣為實驗介質,通過拍照法穫得噴淋塔內液滴粒徑分佈,攷察瞭不同噴淋量及空塔氣速對塔內不同高度處液滴Sauter平均直徑(SMD)的影響,併對液滴粒徑分佈進行瞭理論分析。結果錶明,噴淋塔頂部液滴分佈密集,底部稀疏,液滴群在下落過程中,平均粒徑減小且趨于均勻化;塔頂處液滴 SMD 隨噴淋量的增加而增大,處在塔中下部的液滴 SMD 則隨噴淋量增大而減小,提高空塔氣速,可減小平均粒徑;理論分析認為,液滴粒徑減小主要是由于髮生瞭踫撞破碎的緣故,而塔內液滴大小不一是踫撞的主要原因;通過量綱1化擬閤得到噴淋塔內液滴 SMD 經驗關聯式,其計算結果與實驗值吻閤較好;攷慮液滴破碎的噴淋塔比錶麵積比不攷慮破碎的比錶麵積大70%左右。
이수화공기위실험개질,통과박조법획득분림탑내액적립경분포,고찰료불동분림량급공탑기속대탑내불동고도처액적Sauter평균직경(SMD)적영향,병대액적립경분포진행료이론분석。결과표명,분림탑정부액적분포밀집,저부희소,액적군재하락과정중,평균립경감소차추우균균화;탑정처액적 SMD 수분림량적증가이증대,처재탑중하부적액적 SMD 칙수분림량증대이감소,제고공탑기속,가감소평균립경;이론분석인위,액적립경감소주요시유우발생료팽당파쇄적연고,이탑내액적대소불일시팽당적주요원인;통과량강1화의합득도분림탑내액적 SMD 경험관련식,기계산결과여실험치문합교호;고필액적파쇄적분림탑비표면적비불고필파쇄적비표면적대70%좌우。
The drop size distribution in a spray tower was obtained by means of the photographic technique with air and water as the experimental media. The effects of spray flux and superficial gas velocity on Sauter mean diameter (SMD) of droplets at different heights of the absorption zone were investigated. The drop size distribution was analyzed theoretically. Dense droplets assembled at the top of the tower; on the contrary, droplets became sparse at the bottom. Small and uniform droplets could be formed in the falling process. With increasing spray flux, the SMD of droplets increased at the top of the tower, while decreased at the middle and lower zones. Average droplet diameter decreased with increasing superficial gas velocity. Theoretically, the decrease of droplet size was mainly accounted for by collision and breakup among droplets, which was primarily caused by diversity of droplet diameters. Dimensionless correlation of SMD was proposed, and the calculation results were in good agreement with the actual data. The specific surface area of spray tower with collision and breakup among droplets was about 70% larger than that without collision and breakup.