实验1-配线法求参

1、地下水动力学实验实验一：配线法求参一、实验名称配线法求参。二、实验性质必做。三、实验类型验证、研究。四、实验目的掌握配线法求参的原理，并利用EXCEL或者Visual Basic等编程工具进行配线法的编程分，根据抽水试验资料进行水文地质参数计算。五、实验内容5.1. 原理配线法是地下水动力学中介绍的求取水文地质参数的一大类方法。5.1.1 越流含水层完整井稳定流定流量抽水Hantush-Jacob公式：， 为Bessel函数，可用Excel工程函数库计算，也可利用附录程序BessK0(x)计算。配线法公式：5.1.2 无补给无限承压含水层完整井非稳定流定流量抽水Theis公式：，Theis井函

2、数计算方法很多，其中以多项式逼近最为常用。Allen (1954) and Hastings (1955):式中系数如下：i0-0.577220.267773.9585010.999998.6347621.099652-0.2499118.0590225.6329630.055198.573339.573324-0.0097650.00108程序见附录Exp1(x)函数。配线法：5.1.3 越流含水层完整井非稳定流定流量抽水Hantush-Jacob公式：，可利用附录程序w(x, y)函数计算。配线法：5.2 配线法的Excel表本实验以Theis与Hantush-Jacob井函数为例，介绍用

3、Excel表实现配线法的方法。5.2.1 Theis井函数求参文件名：Theis_test.xlsTheis表中包含双对数坐标的配线法图形，A、B列为抽水实验观测数据(单位：min、m)。Q、R、S列分别为标准曲线的1/u、u、W(u)，图中的标准曲线即是用Q、S列生成的。滚动条ScrollBar1、ScrollBar2控制坐标偏移量。属性如下：Min = 0，Max = 100，LargeChange = 10，SmallChange = 1滚动条ScrollBar1、ScrollBar2的事件过程为：Sub main() ScrollBar1_Change ScrollBar2_Chang

4、eEnd SubPrivate Sub ScrollBar1_Change() With ScrollBar1 delta = Range(H24).Value - Range(G24).Value Range(I24).Value = Range(G24).Value + delta * .Value / 100 End WithEnd SubPrivate Sub ScrollBar1_Scroll() ScrollBar1_ChangeEnd SubPrivate Sub ScrollBar2_Change() With ScrollBar2 delta = Range(H26).Val

5、ue - Range(G26).Value Range(I26).Value = Range(G26).Value + delta * .Value / 100 End WithEnd SubPrivate Sub ScrollBar2_Scroll() ScrollBar2_ChangeEnd Sub横轴、纵轴的偏移量Min、Max分别为双对数坐标的偏移量，向左取负值。Offset为偏移量的对数值，单元格为I24与I26（记为）。单元L23抽水量（）,单元L24为观测孔距抽水井径向距离，L25为计算的T值（），L26为计算的值。$L$23为取单元L23的绝对引用。C、D列为A、B列偏移后的数

6、值，E列为计算误差，公式如下：，参数计算公式：曲线：，曲线：，曲线：，Question表为抽水实验观测数据。Excel图形如下：5.2.2 Hantush-Jacob井函数求参文件名：Hantush-Jacob_test.xlsData表含有不同值的Hantush-Jacob井函数数值表。Hantush-Jacob表中包含双对数坐标的配线法图形，A、B列为抽水实验观测数据，单位为min、m。标准曲线的绘图数据在Data表中。滚动条ScrollBar1、ScrollBar2控制坐标偏移量。属性如下：Min = 0，Max = 100，LargeChange = 10，SmallChange =

7、1滚动条ScrollBar1、ScrollBar2的事件过程为：Sub main() ScrollBar1_Change ScrollBar2_ChangeEnd SubPrivate Sub ScrollBar1_Change() With ScrollBar1 Delta = Range(H27).Value - Range(G27).Value Range(I27).Value = Range(G27).Value + Delta * .Value / 100 End WithEnd SubPrivate Sub ScrollBar1_Scroll() ScrollBar1_Change

8、End SubPrivate Sub ScrollBar2_Change() With ScrollBar2 Delta = Range(H29).Value - Range(G29).Value Range(I29).Value = Range(G29).Value + Delta * .Value / 100 End WithEnd SubPrivate Sub ScrollBar2_Scroll() ScrollBar2_ChangeEnd Sub横轴、纵轴的偏移量Min、Max分别为双对数坐标的偏移量，向左取负值。Offset为偏移量的对数值，单元格为I27与I29（记为）。先移动图形

9、，选择合适的，填入单元L25。单元L26抽水量（）,单元L27为观测孔距抽水井径向距离，L28为计算的T值（），L29为计算的值。$L$25为取单元L25的绝对引用。C、D列为A、B列偏移后的数值，E列为计算误差，公式如下：，参数计算公式：曲线：，曲线：，曲线：，Question表为抽水实验观测数据。Excel图形如下：附录：井函数计算程序 This calculates drawdowns for flow to a well from the Theis solution.Function Exp1(x)A0 = -0.a1 = 0.a2 = -0.A3 = 0.A4 = -0.A5 =

10、0.B0 = 0.B1 = 8.B2 = 18.B3 = 8.B4 = 1c0 = 3.c1 = 21.c2 = 25.c3 = 9.C4 = 1If x = 1 Then Exp1 = -Log(x) + A0 + x * (a1 + x * (a2 + x * (A3 + x * (A4 + x * A5)Else p1 = B0 + x * (B1 + x * (B2 + x * (B3 + x * B4) P2 = c0 + x * (c1 + x * (c2 + x * (c3 + x * C4) Exp1 = (p1 / P2) * Exp(-x) / xEnd IfEnd Fun

11、ction To compute the Hantush leaky-aquifer function W(x,y). Append routines to compute Exp1(x),ExpInt(n,x),BessK0(x),BessI0(x)and BessI1(x).Function w(x, y)If x = 0 Then w = 2 * BessK0(y)Else r = 1 t = y 2 / (4 * x) b = 2 * x If y = b Then w = 0 n = 0 Do term = r * ExpInt(n + 1, x) w = w + term n =

12、n + 1 r = r * (-t) / n Loop Until Abs(term) 0. Else w = 2 * BessK0(y) n = 0 Do term = r * ExpInt(n + 1, t) w = w - term n = n + 1 r = r * (-x) / n Loop Until Abs(term) =0.Function ExpInt(n, x)If n = 0 Then ExpInt = Exp(-x) / xElseIf n = 1 Then ExpInt = Exp1(x)ElseIf (n 1) And (x 1) And (x 5) Then N1

13、 = Int(x) t = x + N1 a = 1 + N1 / t 2 + N1 * (N1 - 2 * x) / t 4 + N1 * (6 * x 2 - 8 * N1 * x + N1 2) / t 6 a = a * Exp(-x) / t If n n i = i - 1 a = (Exp(-x) - i * a) / x Loop ExpInt = a Else i = N1 Do While i n i = i + 1 a = (Exp(-x) - x * a) / (i - 1) Loop ExpInt = a End IfEnd IfEnd Function To cal

14、culate the modified Bessel function K0(x) for 0xinfinity.Function BessK0(x)A0 = -0.a1 = 0.a2 = 0.A3 = 0.A4 = 0.A5 = 0.A6 = 0.B0 = 1.B1 = -0.B2 = 0.B3 = -0.B4 = 0.B5 = -0.B6 = 0.If x = 2 Then t = (x / 2) 2 BessK0 = A0 + t * (a1 + t * (a2 + t * (A3 + t * (A4 + t * (A5 + t * A6) BessK0 = BessK0 - Appli

15、cation.Ln(x / 2) * BessI0(x)Else t = 2 / x BessK0 = B0 + t * (B1 + t * (B2 + t * (B3 + t * (B4 + t * (B5 + t * B6) BessK0 = BessK0 * Exp(-x) / Sqr(x)End IfEnd Function To compute the modified Bessel function I0(x) for 0xinfinity.Function BessI0(x)A0 = 1a1 = 3.a2 = 3.A3 = 1.A4 = 0.A5 = 0.A6 = 0.B0 = 0.B1 = 0.B2 = 0.B3 = -0.B4 = 0.B5 = -0.B6 = 0.B7 = -0.B8 = 0.If x = 3.75 Then t = (x /