求各位大佬们帮帮忙，下面是我写的代码：
Kang = (210*10^9)/(1 - 0.09)*1/12*0.2*0.0032^3;
rou = 7800;
zukang = 1668*200;
lamana = 0.1;
Td = 0.004;
P0 = 124234.645;
aef = 0.8;
l = 0.2;
A = 0.2*0.0032;
wn = Sqrt[Kang/(rou*A)]*((n*Pi)/l)^2;
Wn = Sqrt[2/(rou*A*l)]*Sin[(n*Pi*0.1)/l];
kesin = zukang/(rou*A)/(2*wn);
Dn1 = (1 - (-1)^n)*l/(n*Pi)*Sqrt[2/(rou*A*l)]*P0*aef;
Dn2 = (-kesin + Sqrt[kesin^2 - 1])*wn;
Dn3 = (-kesin - Sqrt[kesin^2 - 1])*wn;
Dn4 = Sqrt[1 - kesin^2]*wn;
En1 = -1*(Dn1*(2*kesin*Dn3 + wn))/(wn^4*lamana*Td*Sqrt[kesin^2 - 1]);
Fn1 = (Dn1*(2*kesin*Dn2 + wn))/(wn^4*lamana*Td*Sqrt[kesin^2 - 1]);
qn1[t_] :=
En1*Exp[Dn2*t] +
Fn1*Exp[Dn3*t] + (2*Dn1)/(wn^2*lamana*Td)*(t - (2*kesin)/wn);
En2 = (2*(2*kesin^2 - 1)*Dn1)/(wn^2*lamana*Td*Dn4);
Fn2 = (4*kesin*Dn1)/(wn^3*lamana*Td);
qn2[t_] :=
Exp[-kesin*wn*t]*(En2*Sin[Dn4*t] + Fn2*Cos[Dn4*t]) + (2*Dn1)/(
wn^2*lamana*Td)*(t - (2*kesin)/wn);
Gn1 = qn1[lamana*Td];
Gn2 = qn2[lamana*Td];
Hn1 = qn1'[lamana*Td];
Hn2 = qn2'[lamana*Td];
En3 = 1/(
2*wn*Sqrt[
kesin^2 - 1])*(Hn1 + (2*Dn1)/(wn^2*(1 - lamana)*Td) -
Dn3*(Gn1 - (2*Dn1)/wn^2*(1 + (2*kesin)/(wn*(1 - lamana)*Td))));
Fn3 = -1/(
2*wn*Sqrt[
kesin^2 - 1])*(Hn1 + (2*Dn1)/(wn^2*(1 - lamana)*Td) -
Dn2*(Gn1 - (2*Dn1)/wn^2*(1 + (2*kesin)/(wn*(1 - lamana)*Td))));
qn3[t_] :=
En3*Exp[Dn2*(t - lamana*Td)] +
Fn3*Exp[Dn3*(t - lamana*Td)] + (2*Dn1)/
wn^2*(1 - (t - lamana*Td)/((1 - lamana)*Td) + (2*kesin)/(
wn*(1 - lamana)*Td));
En4 = 1/Dn4*(Hn2 +
kesin*wn*(Gn2 - (2*Dn1)/
wn^2*(1 + (2*kesin)/(wn*(1 - lamana)*Td))) + (2*Dn1)/(
wn^2*(1 - lamana)*Td));
Fn4 = Gn2 - (2*Dn1)/wn^2*(1 + (2*kesin)/(wn*(1 - lamana)*Td));
qn4[t_] :=
Exp[-kesin*wn*(t - lamana*Td)]*(En4*Sin[Dn4*(t - lamana*Td)] +
Fn4*Cos[Dn4*(t - lamana*Td)]) + (2*Dn1)/
wn^2*(1 - (t - lamana*Td)/((1 - lamana)*Td) + (2*kesin)/(
wn*(1 - lamana)*Td));
Plot[Piecewise[{{\!\(
\*UnderoverscriptBox[\(\[Sum]\), \(n = 1\), \(5\)]\((Wn*
qn1[t])\)\) + \!\(
\*UnderoverscriptBox[\(\[Sum]\), \(n = 6\), \(30\)]\((Wn*qn2[t])\)\),
0 < t < 0.0004}, {\!\(
\*UnderoverscriptBox[\(\[Sum]\), \(n = 1\), \(5\)]\((Wn*
qn3[t])\)\) + \!\(
\*UnderoverscriptBox[\(\[Sum]\), \(n = 6\), \(30\)]\((Wn*qn4[t])\)\),
0.0004 < t < 0.004}}], {t, 0, 0.004}]
我画出的图与文献中（虚线）并不相符，求各位大佬指点迷津。

而且改变kang这个参数，在文献中图像有变化，而我写的公式中改变kang这个参数无变化（除了0）。