Re>1×105:
4.阻力压降
3、驱动压头
4、迭代方式
5、程序代码
Publicm(0To50),e(0To50),n(0To50)AsSingle‘子块公用变量定义
PrivateSubCommand2_Click()
Text1.Text=""
Text2.Text=""
Picture1.Cls
EndSub
PrivateSubCommand3_Click()
End
EndSub
PrivateSubCommand1_Click()
Picture1.Cls
a1=2.01061929829747E-04'大管截面积m2
a2=5.02654824574367E-05'小管截面积m2
q=Val(Text1)
tin=Val(Text2)
hi=ttoh(tin)
pi=ttom(tin)
qm=q/(ttoh(100)-hi)
l=qm/10000
pd=2
pz=1
i=1
re:
If(pd>pz)Then
qm=qm+l
ho=hi+q/qm
tout=htot(ho)
po=ttom(tout)
p1=0.5*qm^2/a1^2*(2.4/pi+0.8/po)
p2=0.5*qm^2/a2^2*(9/(16*pi)+1/(2*po))
p3=0.5*qm^2/a1^2*(1.5/(pi+po))
re=qm*0.016/(pi*a1*ttou(tin))
p4=0.5*qm^2*500*f(re)/(pi*a1^2)
re=qm*0.016/(po*a1*ttou(tout))
p5=0.5*qm^2*250*f(re)/(po*a1^2)
re=qm*0.008/((pi+po)*a2*ttou((tin+tout)/2)/2)
p6=0.5*qm^2*250*f(re)/((pi+po)*a2^2/2)
pz=p1+p2+p3+p4+p5+p6
pd=(pi-po)*49.05/2
i=i+1
GoTore
ElseIf(i=2)Then
Picture1.PrintvbCrLf
Picture1.Print"不能建立单相自然循环"
EndIf
If(Abs(pd-pz)*100/pd>=5Andi>2)Then
Picture1.PrintvbCrLf
Picture1.Print"压力误差:
";Spc
(1);Format((pd-pz)*100/pd,"0.000");"%"
Picture1.Print"循环次数:
";Spc
(1);Format(i,"0");"次"
Picture1.Print"出口温度:
";Spc
(1);Format(tout,"0.00");"℃"
Picture1.Print"出口焓值:
";Spc
(1);Format(ho,"0.00");"kJ/kg"
Picture1.Print"出口密度:
";Spc
(1);Format(po,"0.000");"kg/m^3"
Picture1.Print"循环流量:
";Spc
(1);Format(qm*1000,"0.00");"g/s"
Picture1.Print"入口焓值:
";Spc
(1);Format(hi,"0.00");"kJ/kg"
Picture1.Print"阻力压降:
";Spc
(1);Format(pz,"0.00");"Pa"
Picture1.Print"驱动压力:
";Spc
(1);Format(pd,"0.00");"Pa"
Picture1.Print"误差过大,请修正参数"
Else
Picture1.PrintvbCrLf
Picture1.Print"出口温度:
";Spc
(1);Format(tout,"0.00");"℃"
Picture1.Print"出口焓值:
";Spc
(1);Format(ho,"0.00");"kJ/kg"
Picture1.Print"出口密度:
";Spc
(1);Format(po,"0.000");"kg/m^3"
Picture1.Print"循环流量:
";Spc
(1);Format(qm*1000,"0.00");"g/s"
Picture1.Print"入口焓值:
";Spc
(1);Format(hi,"0.00");"kJ/kg"
Picture1.Print"阻力压降:
";Spc
(1);Format(pz,"0.00");"Pa"
Picture1.Print"驱动压力:
";Spc
(1);Format(pd,"0.00");"Pa"
Picture1.Print"压力误差:
";Spc
(1);Format((pd-pz)*1000/pd,"0.00");"‰"
Picture1.Print"循环次数:
";Spc
(1);Format(i,"0");"次"
EndIf
EndSub
PrivateSubForm_Load()
Dimtin,tout,pi,po,hi,ho,re,q,qmAsSingle'入口温度,出口温度,入口密度,出口密度,入口焓值,出口焓值,雷诺数,功率,流量
Dimp1,p2,p3,p4,p5,p6,pz,pdAsSingle'各项阻力
Dimi,j,k,l,teAsSingle
Dima1,a2AsSingle
Open"f:
\密度值.txt"ForInputAs#1'密度数值表输入,2度一值,共51
Forj=0To50
LineInput#1,inputdata
m(j)=Val(inputdata)
Nextj
Close#1
Open"f:
\比焓值.txt"ForInputAs#2'比焓值值表输入,2度一值,共51
Forj=0To50
LineInput#2,inputdata
e(j)=Val(inputdata)
Nextj
Close#2
Open"f:
\粘性系数.txt"ForInputAs#3'粘性系数表输入,2度一值,共51
Forj=0To50
LineInput#3,inputdata
n(j)=Val(inputdata)
Nextj
Close#3
EndSub
Functionhtot(h)
j=0'由焓值求温度
re:
If(h>=e(j)Andh<=e(j+1))Then
htot=2*j+2*(h-e(j))/(e(j+1)-e(j))
Else:
j=j+1
GoTore
EndIf
EndFunction
Functionttoh(t)
k=Int(t/2)
If(t=2*k)Then
ttoh=e(k)
Else
ttoh=e(k)+(t/2-k)*(e(k+1)-e(k))/2'由温度求焓值
EndIf
EndFunction
Functionmtot(p)
j=0
re:
If(p<=m(j)Andp>=m(j+1))Then
mtot=2*j+2*(p-m(j))/(m(j+1)-m(j))
Else:
j=j+1
GoTore
EndIf
EndFunction
Functionttom(t)
k=Int(t/2)
If(t=2*k)Then
ttom=m(k)
Else
ttom=m(k)+(t/2-k)*(m(k+1)-m(k))/2'由温度求密度
EndIf
EndFunction
Functionttou(t)
k=Int(t/2)
If(t=2*k)Then
ttou=n(k)
Else
ttou=n(k)+(t/2-k)*(n(k+1)-n(k))/2'由温度求粘性系数
EndIf
EndFunction
Functionf(re)
'沿程阻力系数计算
If