请高手用MATLAB帮忙解下微分方程组教下：Dy(1)=y(2);Dy(2)=y(3)^2*u*A*N^2/(2*m*(L-y(1))^2)-C/m*y(2)-k*(l+y(1))/m-(f+F)/m;Dy(3)=(L-y(1))/(u*A*N^2)*(V-y(3)*y(2)*u*A*N^2/(L-y(1))^2-R*y(3));初步带入数据如下：m=0.6;N=500;V=24;C=0.5

Question

请高手用MATLAB帮忙解下微分方程组教下：
Dy(1)=y(2);
Dy(2)=y(3)^2*u*A*N^2/(2*m*(L-y(1))^2)-C/m*y(2)-k*(l+y(1))/m-(f+F)/m;
Dy(3)=(L-y(1))/(u*A*N^2)*(V-y(3)*y(2)*u*A*N^2/(L-y(1))^2-R*y(3));
初步带入数据如下：
m=0.6;
N=500;
V=24;
C=0.5;
k=500;
l=0.0095;
f=16;
F=7;
L=0.0149;
r=0.034;
u=1.256e-6;
R=1;
A=pi*r^2;
时间t=10s，初始值y=【0 0 0】

Answer 1

clear;clc
[T,Y]=ode45('nobk',[0 5],[0;0;0]) %微分方程有问题,求出来的都是0
plot(T,Y(:,1))
---------------------
function dy=nobk(t,y)
m=0.6;
N=500;
V=24;
C=0.5;
k=500;
l=0.0095;
f=16;
F=7;
L=0.0149;
r=0.034;
u=1.256e-6;
R=1;
A=pi*r^2;
dy=[0;0;0];
Dy(1)=y(2);
Dy(2)=y(3)^2*u*A*N^2/(2*m*(L-y(1))^2)-C/m*y(2)-k*(l+y(1))/m-(f+F)/m;
Dy(3)=(L-y(1))/(u*A*N^2)*(V-y(3)*y(2)*u*A*N^2/(L-y(1))^2-R*y(3));