The left to right shunt rate (f) and the transverse sectional area of ductus arteriosus (a) were calculated by color Doppler flow convergence method in 20 patients with patent ductus arteriosus.
用彩色多普勒血流会聚法对20例动脉导管未闭患者的左向右分流率F进行测定，并根据F值计算出动脉导管的横截面积A。
Time dependent calculation for a suddenly imposed pressure gradient has shown that variation of the cross sectional area reduces inertial effect in the contraction flow region.
压力差为阶跃变化的情况下数值计算结果说明了收缩部的断面积的时间变化减少了收缩部的惯性效果。
In a steady internal flow the Mach number can only reach 1 at a minimum in the cross-sectional area.
在一个稳定的内部流动马赫数只能达到一在最低限度，在截面积。
In a steady internal flow the Mach number can only reach 1 at a minimum in the cross-sectional area.
在一个稳定的内部流动马赫数只能达到一在最低限度，在截面积。
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