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1、基于VB编程的水泵拟合实现1条件综述1.1 拟合条件已知水泵的四个工况点流量、扬程、功率以及空调水系统管网的阻力系数，拟合水泵（并联）的特性曲线以及管网的特性曲线。1.2 样本条件本次编程选用南方泵业TD100及TD150系列四种型号的水泵。模拟的供热系统各参数分别为：供热面积：200000平方米；面积热指标：45W/m2；供回水温度：95/70；系统阻力：37米水柱。2 编程要求循环水泵特性曲线拟合：多台同型号水泵并联，根据水泵并联特性通过计算机编程计算，求水泵工作点。考虑单台或多台循环水泵运行时，比较其流量、扬程、效率、轴功率如何变化，画出水泵和管网特性曲线。3 水泵拟合求解思路从水泵性能
2、曲线图可看出水泵的扬程、功率和效率是流量的多项式。因此可以表示为：H=H0+A1G+A2G2+A3G3 N=N0+B1G+B2G2+B3G3 =(G*H*1000)/N*100*3600式中 G水泵流量，m3/h； H水泵扬程，mH2O； 水泵效率，%； N水泵轴功率，kW上面方程组的系数A1、A2、A3和H0可由最小二乘法得到：为了编程语言的方便,其中上列方程组中的系数A1、A2、A3和H0分别由X1、X2、X3、X4代替，即：具体方程组的求解是利用高斯赛德尔迭代法迭代公式为：解出X(1)等各个系数，同理解出B1、B2、B3、N0。再利用公式=(G*H*1000)/N*100*3600求出。
3、从而确定GH、G、GN回归曲线方程。根据回归曲线方程则可以画出水泵的性能曲线。4 程序代码及注释水泵参考工作点数据库的建立程序代码为：（1） 主界面和开始界面的转换：Private Sub cmdJr_Click()Frm1.Hide 隐藏开始界面Frm2.Show 显示程序主界面End SubPrivate Sub cmdTc_Click()EndEnd Sub（2） 赋值和管网阻力系数的计算：Option ExplicitDim G As Single, N As Single, H As Single, S As Single, z As Single, Zl As Single, Tg
4、 As Single, Th As Single, Dt As Single, M As Single 定义变量Dim X(1 To 4) As Double, Y(1 To 4) As Double, A(1 To 4, 1 To 4) As Double, B(1 To 4, 1 To 4) As DoublePrivate Sub cmdM1_Click()txtMj.Text = 200000 面积赋值txtZb.Text = 45 采暖热指标赋值txtGs.Text = 95 供水温度txtHs.Text = 70 回水温度txtZl.Text = 37 系统阻力End SubPri
5、vate Sub cmdJs_Click()If txtMj.Text = ThenMsgBox 请输入数据ElseM = Val(txtMj.Text)z = Val(txtZb.Text)Zl = Val(txtZl.Text)Tg = Val(txtGs.Text)Th = Val(txtHs.Text)Dt = Tg Th 供回水温差G = M * z * 3.6 / (4187 * Dt)txtLl.Text = GS = Zl / (G * G) 阻力系数计算txtXs.Text = SEnd IfEnd Sub（3） 水泵选型及赋值：Private Sub cmdSb_Click
6、()If comSb.Text = comSb.List(0) ThentxtQ(0).Text = 40txtQ(1).Text = 80txtQ(2).Text = 120txtQ(3).Text = 160txtH(0).Text = 16.8txtH(1).Text = 17.1txtH(2).Text = 16.3txtH(3).Text = 15txtN(0).Text = 5txtN(1).Text = 6txtN(2).Text = 7.7txtN(3).Text = 8.9End IfIf comSb.Text = comSb.List(1) ThentxtQ(0).Text
7、 = 40txtQ(1).Text = 100txtQ(2).Text = 140txtQ(3).Text = 200txtH(0).Text = 34.6txtH(1).Text = 34.7txtH(2).Text = 34.4txtH(3).Text = 33txtN(0).Text = 12txtN(1).Text = 17txtN(2).Text = 20.1txtN(3).Text = 25End IfIf comSb.Text = comSb.List(2) ThentxtQ(0).Text = 40txtQ(1).Text = 100txtQ(2).Text = 140txtQ
8、(3).Text = 200txtH(0).Text = 42.5txtH(1).Text = 42.6txtH(2).Text = 42txtH(3).Text = 40txtN(0).Text = 15txtN(1).Text = 21txtN(2).Text = 27txtN(3).Text = 30.8End IfIf comSb.Text = comSb.List(3) ThentxtQ(0).Text = 20txtQ(1).Text = 40txtQ(2).Text = 60txtQ(3).Text = 80txtH(0).Text = 29txtH(1).Text = 28.5
9、txtH(2).Text = 27.5txtH(3).Text = 26.5txtN(0).Text = 4.2txtN(1).Text = 5txtN(2).Text = 5.6txtN(3).Text = 6.5End IfIf comSb.Text = 请选择 Then 提示选择水泵MsgBox 请选择水泵End IfIf comSb.Text = ThenMsgBox 请选择水泵End IfEnd SubPrivate Sub cmdOne_Click(Index As Integer)If comSb.Text = 请选择 Then MsgBox 请选择水泵End IfIf comS
10、b.Text = ThenMsgBox 请选择水泵End If（4） 方程求解及单台水泵曲线绘制：Dim c As Single, d As Single, ef As Single 定义变量Dim i As Integer, j As Integer, xk As Single, yk As SingleDim B1(1 To 4) As Single, B2(1 To 4) As SingleA(1, 1) = 4 最小二乘法A(1, 2) = 0For i = 1 To 4 A(1, 2) = A(1, 2) + Val(txtQ(i - 1).Text)Next iA(1, 3) =
11、0For i = 1 To 4 A(1, 3) = A(1, 3) + Val(txtQ(i - 1).Text) 2Next iA(1, 4) = 0For i = 1 To 4 A(1, 4) = A(1, 4) + Val(txtQ(i - 1).Text) 3Next iA(2, 4) = 0For i = 1 To 4 A(2, 4) = A(2, 4) + Val(txtQ(i - 1).Text) 4Next iA(3, 4) = 0For i = 1 To 4 A(3, 4) = A(3, 4) + Val(txtQ(i - 1).Text) 5Next iA(4, 4) =
12、0For i = 1 To 4 A(4, 4) = A(4, 4) + Val(txtQ(i - 1).Text) 6Next iA(2, 1) = A(1, 2): A(2, 2) = A(1, 3): A(2, 3) = A(1, 4)A(3, 1) = A(1, 3): A(3, 2) = A(1, 4): A(3, 3) = A(2, 4)A(4, 1) = A(1, 4): A(4, 2) = A(2, 4): A(4, 3) = A(3, 4)B1(1) = 0For i = 1 To 4 B1(1) = B1(1) + Val(txtH(i - 1).Text)Next iB1(
13、2) = 0For i = 1 To 4 B1(2) = B1(2) + Val(txtH(i - 1).Text) * Val(txtQ(i - 1).Text)Next iB1(3) = 0For i = 1 To 4 B1(3) = B1(3) + Val(txtH(i - 1).Text) * Val(txtQ(i - 1).Text) 2Next iB1(4) = 0For i = 1 To 4 B1(4) = B1(4) + Val(txtH(i - 1).Text) * Val(txtQ(i - 1).Text) 3Next iB2(1) = 0For i = 1 To 4 B2
14、(1) = B2(1) + Val(txtN(i - 1).Text)Next iB2(2) = 0For i = 1 To 4 B2(2) = B2(2) + Val(txtN(i - 1).Text) * Val(txtQ(i - 1).Text)Next iB2(3) = 0For i = 1 To 4 B2(3) = B2(3) + Val(txtN(i - 1).Text) * Val(txtQ(i - 1).Text) 2Next iB2(4) = 0For i = 1 To 4 B2(4) = B2(4) + Val(txtN(i - 1).Text) * Val(txtQ(i
15、- 1).Text) 3Next i For i = 1 To 4 用高斯-赛德尔迭代法计算 X(i) = 0Next i Do For i = 1 To 4 xk = B1(i) For j = 1 To 4 If i j Then xk = xk - A(i, j) * X(j) Next j xk = xk / A(i, i) c = Abs(xk - X(i) X(i) = xk Next i Loop Until c 0.0001For i = 1 To 4 Y(i) = 0Next i Do For i = 1 To 4 yk = B2(i) For j = 1 To 4 If i
16、 j Then yk = yk - A(i, j) * Y(j) Next j yk = yk / A(i, i) d = Abs(yk - Y(i) Y(i) = yk Next i Loop Until d 0 Then picT.PSet (G, (G * H / N / 3.6) * 0.1 + 45), vbGreen End IfNext GpicT.Scale (0, 60)-(750, 0)DrawWidth = 1 模拟管网性能曲线For G = 0 To 750 H = S * G 2 picT.PSet (G, H), vbBlueNext G求单台水泵实际工作点参数Di
17、m h1 As SingleFor G = 0 To 750 H = X(1) + X(2) * G + X(3) * G 2 + X(4) * G 3 N = Y(1) + Y(2) * G + Y(3) * G 2 + Y(4) * G 3 h1 = S * G 2If Abs(H - h1) 1 Then ef = G * H / (N * 3.6) If ef 30 Then MsgBox 效率太低，请选择其它型号水泵 Else txtOneg.Text = Format(G, 0.000) txtOneh.Text = Format(H, 0.000) txtOnee.Text =
18、Format(G * H / (N * 3.6) * 0.1 + 45, 0.000) txtOnen.Text = Format(Y(1) + Y(2) * G + Y(3) * G 2 + Y(4) * G 3) * 0.4, 0.000) End If Exit For End IfNext GEnd Sub（5） 模拟多台水泵并联及水泵工作点的确定：Private Sub cmdDuo_Click(Index As Integer) If comSl.Text = 请选择 Then MsgBox 请选择并联水泵数量End IfIf comSl.Text = ThenMsgBox 请选择
19、并联水泵数量End IfDim i As Integer, k As Integer, h1 As Single, ef As Single For i = 0 To 3 If comSl.Text = comSl.List(i) Then picT.Scale (0, 60)-(750, 0) For G = 0 To 750 H = X(1) + X(2) * (G / (i + 2) + X(3) * (G / (i + 2) 2 + X(4) * (G / (i + 2) 3 N = Y(1) + Y(2) * (G / (i + 2) + Y(3) * (G / (i + 2) 2
20、+ Y(4) * (G / (i + 2) 3 DrawWidth = 2 picT.PSet (G, H), vbRed h1 = S * G 2 If Abs(H - h1) 1 Then ef = G * H / (N * 3.6) If ef 30 Then MsgBox 效率太低，请选择其它型号水泵! Else txtDuog.Text = Format(G, 0.000) 实际工作点 txtDuoh.Text = Format(H, 0.000) txtDuoe.Text = Format(G * H / (N * 3.6 * (i + 2) * 0.1 + 45, 0.000)t
21、xtDuon.Text = Format(Y(1) + Y(2) * (G / (i + 2) + Y(3) * (G / (i + 2) 2 + Y(4) * (G / (i + 2) 3) * 0.4, 0.000) End If End If Next G End IfNext iEnd Sub（6） 窗口清空及退出：Private Sub cmdClear_Click() txtMj.Text = txtZb.Text = txtGs.Text = txtHs.Text = txtZl.Text = txtXs.Text = txtLl.Text = txtQ(0).Text = tx
22、tQ(1).Text = txtQ(2).Text = txtQ(3).Text = txtH(0).Text = txtH(1).Text = txtH(2).Text = txtH(3).Text = txtN(0).Text = txtN(1).Text = txtN(2).Text = txtN(3).Text = txtOneg.Text = txtOneh.Text = txtOnee.Text = txtOnen.Text = txtDuog.Text = txtDuoh.Text = txtDuon.Text = txtDuoe.Text = comSb.Text = 请选择c
23、omSl.Text = 请选择picT.Picture = LoadPicture()End SubPrivate Sub cmdQuit_Click()EndEnd Sub5结果分析5.1 分步模拟 (1)当水泵型号选择南方TD100-25/2时，水泵台数为1台，管网阻力系数为0.0000386 h2/m5曲线拟合后单台水泵工作点为：流量221 m3/h、扬程19.831 mh2o、功率4.809kwh、效率55.126%。拟合后的曲线为：(2)当水泵型号选择南方TD100-25/2时，水泵台数为2台，曲线拟合后单台水泵工作点为：流量260m3/h、扬程25.263mh2o、功率3.013k
24、wh、效率57.112%。拟合后的曲线为： (3)当水泵型号选择TD100-25/2时，水泵台数为3台，曲线拟合后单台水泵工作点为：流量267m3/h、扬程26.568mh2o、功率2.576kwh、效率58.198%。拟合后的曲线为：(4) 当水泵型号选择TD100-25/2时，水泵台数为4台，曲线拟合后单台水泵工作点为：流量269m3/h、扬程27.048mh2o、功率2.414kwh、效率59.371%。拟合后的曲线为：5.1 结果分析综合上述，得到下表：水泵并联台数流量 m3/h扬程 mh2o功率 kw效率122119.8314.80955.126%226025.2633.01357.
25、112%326726.562.57658.198%426927.0482.41459.371%分析结论：从上面的曲线拟合结果可以得出结论，随着并联水泵台数的增加单台水泵的流量增加，扬程增加、功率减少、效率提高。6 程序使用说明6.1 开始界面打开程序进入开始界面，如下图。点击“进入程序”，进入计算主界面；点击“退出程序”，退出。6.2 计算主界面及操作过程操作过程：1 点击“模拟赋值”，进行对供热系统的赋值，或者自行输入参数；2 点击“计算流量与阻力”，计算阻力系数；3 选择水泵并赋值；4 点击“单台水泵拟合”，计算和画出单台水泵曲线及管网曲线；5 选择并联台数，点击“多台水泵拟合”，绘制多台水泵拟合曲线。
