一种求解S形进气道三维粘性流场的多重网格算法

A MULTIGRID ALGORITHM OF 3 D VISCOUS INTERNAL FLOW FIELD FOR S SHAPED INLET

关键词:  进气道  流场仿真  格网法  三维流  纳维尔－斯托克斯方程

Key words:  Inlet  Flow field simulation  Grids method  Three dimensional flow  Navier Stokes equation

摘要:

提出了一种基于多重网格技术，可快速求解Ｓ形进气道粘性内流场的实用工程算法：从Ｂｒａｎｄｔ的多重网格理论出发，采用隐式Ｂｅａｍ－Ｗａｒｍｉｎｇ时间推进格式，结合“锯齿式”迭代技术交替在粗、细两种网格上对雷诺平均三维非定常Ｎ－Ｓ方程进行求解。用此算法数值模拟了某型号Ｓ形进气道的内流场，与试验结果对比显示：计算得到的流场符合一般Ｓ形管道流动特性，所捕获的二次流图谱清晰合理，进气道出口截面处总压恢复系数与试验值较为接近。与普通单层网格计算方法相比，计算结果精度高，收敛速度快。

Abstract:

A practical engineering oriented algorithm based on multi grid technique is presented for computing full viscous internal flow in a S shaped inlet.The algorithm originates from Brandt′s multi grid theory and sloves 3 D Reynolds average N S equation with time marching implicit scheme of Beam Warming from fine grid levels through coarse ones in conjunction with“saw”shape iteration.The technique developed is employed to simulate the internal flow in a S shaped inlets and compared with experimental data.The comparative analysis demonstrates that the convergence results obtained by the algorithm is in agreement with general flow characteristics in S shaped duct,the secondary flow graphs captured are rational and clear and the total pressure recovery at exit cross section agrees with experimental data.Both convergence speed and computational accuracy are higher than ordinary single level′s.It is a reliable practical algorithm.