The earthwork grill buries is buried may have the virtual impedance function 土工格栅埋入土中可产生有效阻抗作用。
2.
The theoretic calculating method of the maximum and the minimum water level in the differential surge tank has been derived firstly . also the explicit method of calculating surges in the differential surge tank has been deduced firstly by use of thaler series expansion . the calculating method of section of the well and the effective impedance hole in the surge tank has been gived 根据差动式调压室的基本微分方程，首次推导出了差动式调压室涌浪幅值的理论计算公式；并同样利用泰勒级数展开方法推导出了差动式调压室水位波动的显式计算式；导出了差动式调压室大井面积和有效阻抗孔面积的计算方法。
