化工进展
化工進展
화공진전
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS
2014年
5期
1118-1122,1169
,共6页
圆盘涡轮式桨叶%混合性能%安装高度%倾角%计算流体力学
圓盤渦輪式槳葉%混閤性能%安裝高度%傾角%計算流體力學
원반와륜식장협%혼합성능%안장고도%경각%계산류체역학
disc turbine blades%mixing performance%installation height%inclined angle%CFD
利用 CFD 技术对圆盘涡轮式搅拌槽内的浓度场进行数值模拟研究,主要考察了常见的平直桨叶(90°)、斜桨叶(60°和45°)的安装位置对混合时间θm、单位体积混合能Wr和浓度标准差σ的影响。在标准安装高度的平直桨叶下,对槽内速度进行分析,得到的数据与实验值非常吻合。研究表明:圆盘涡轮式桨叶由标准安装高度降低时,搅拌槽内的流型由径向流转变为轴向流,并且90°、60°和45°的转变为轴向流的相对安装高度(C/H)分别为0.20、0.233和0.267;混合时间是由槽内顶部和底部检测位置决定的;桨叶的标准相对安装高度(C/H=1/3)并不是混合性能最优的位置,针对90°、60°和45°三种倾角的桨叶,在相对安装高度分别为0.213、0.267和0.320时的搅拌混合性能最佳;综合考虑省时、节能和混合均匀性的因素,倾角为45°的桨叶最佳,60°的桨叶次之。
利用 CFD 技術對圓盤渦輪式攪拌槽內的濃度場進行數值模擬研究,主要攷察瞭常見的平直槳葉(90°)、斜槳葉(60°和45°)的安裝位置對混閤時間θm、單位體積混閤能Wr和濃度標準差σ的影響。在標準安裝高度的平直槳葉下,對槽內速度進行分析,得到的數據與實驗值非常吻閤。研究錶明:圓盤渦輪式槳葉由標準安裝高度降低時,攪拌槽內的流型由徑嚮流轉變為軸嚮流,併且90°、60°和45°的轉變為軸嚮流的相對安裝高度(C/H)分彆為0.20、0.233和0.267;混閤時間是由槽內頂部和底部檢測位置決定的;槳葉的標準相對安裝高度(C/H=1/3)併不是混閤性能最優的位置,針對90°、60°和45°三種傾角的槳葉,在相對安裝高度分彆為0.213、0.267和0.320時的攪拌混閤性能最佳;綜閤攷慮省時、節能和混閤均勻性的因素,傾角為45°的槳葉最佳,60°的槳葉次之。
이용 CFD 기술대원반와륜식교반조내적농도장진행수치모의연구,주요고찰료상견적평직장협(90°)、사장협(60°화45°)적안장위치대혼합시간θm、단위체적혼합능Wr화농도표준차σ적영향。재표준안장고도적평직장협하,대조내속도진행분석,득도적수거여실험치비상문합。연구표명:원반와륜식장협유표준안장고도강저시,교반조내적류형유경향류전변위축향류,병차90°、60°화45°적전변위축향류적상대안장고도(C/H)분별위0.20、0.233화0.267;혼합시간시유조내정부화저부검측위치결정적;장협적표준상대안장고도(C/H=1/3)병불시혼합성능최우적위치,침대90°、60°화45°삼충경각적장협,재상대안장고도분별위0.213、0.267화0.320시적교반혼합성능최가;종합고필성시、절능화혼합균균성적인소,경각위45°적장협최가,60°적장협차지。
Concentration field in the stirred tank with disc turbine paddle was studied by numerical simulation method CFD. This paper mainly investigated the effects of the location of the common straight blade (90° ) and inclined blades (60° and 45°) on mixed timeθm,mixing energy per unit volume Wr and the concentration standard deviation of mixing σ. The data of simulation speed agreed well with experimental data under the standard installation height of straight blade. The research showed that flow pattern within the mixing tank turns from radial flow into axial flow when the installation height of disc turbine blade is decreased from the standard height. The relative installation height (C/H ) of 90°,60° and 45° paddle was 0.20,0.233 and 0.267 respectively when flow pattern turned into axial flow. Mixing time was decided by the top and bottom detection positions of tank. The standard relative installation height (C/H=1/3 ) was not the optimal location of the mixing performance. The mixing performance of 90°,60° and 45° blades was optimal when the relative installation height was at 0.313,0.267 and 0.320 respectively. Combing the advantages of saving time, energy and mixing uniformity,blade of 45° was the best and 60o took the second place.