Abstract: 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 time θm，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.

Key words: disc turbine blades, mixing performance, installation height, inclined angle, CFD

摘要： 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。

关键词: 圆盘涡轮式桨叶, 混合性能, 安装高度, 倾角, 计算流体力学