In order to make the run without a hitch , the Computational Fluid Dynamic ( CFD ) and the Orthogonal Experiment Design were utilized to model the effect of three parameters .The range analysis and the variance analysis were also used to discover the objective laws about velocity uniformity .The impact factors ranking was orifice diameter , orifice location and the combination of total and dynamic pressure .Orifice diameter was the main influence factor showed in the further study . The smaller orifice diameter was , the more uniformly inlet flowed .Orifice location was the secondary influence factor . When the location was above the vertical plane of the center , inlet flowed uniformly .For the parameters of the inlet fan , it had little impact to uniformity .By the actual production situation analysis , the optimal combination was obtained , that is, orifice diameter was 40 mm, location was 2/5, and the inlet total pressure and dynamic pressure of the fan were 690 and 90 Pa, respectively.For this case, the orifice flow velocity asymmetry coefficient was 0.035, the maximum speed deviation was 9%, and average speed was 15.7 m/s.%利用计算流体力学数值模拟、正交试验极差和方差分析等方法,仿真模拟木材干燥室进气道孔口位置、孔口直径、进气风机全压与动压组合3个因素对进气孔口气流均匀性的影响规律.结果表明:3个因素对进气孔口气流速度、风压均匀性的影响程度从大到小依次为孔口直径、孔口位置、进气风机风压.在35~50 mm范围内,孔口直径越小,气流均匀性越好;孔口位置在靠近竖直平面中心偏上时,气流均匀性更好;进气风机全压与动压组合对气流均匀性的影响程度较低.根据分析结果和实际生产现状,综合得出气流均匀性最优时孔口直径40 mm,孔口位置距竖直平面上端2/5处,进气风机全压690 Pa、动压90 Pa.按照这些参数设计的进气孔口气流速度不均匀性系数0.035,最大速度偏差9%,平均气流速度15.7 m/s,孔口气流均匀性可满足生产实际要求.
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