课程设计（论文）基于VB编程的水泵拟合实现

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comsl.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