pimx2.m

内燃机转子仿真

%f1=0 f2=10*cos(wt)  w=60rad/s
clear all;
%function []=pimx2(w)
clc;
close all;
format short;
n=2;
we=[0.2369269 0.4786287 0.5688889 0.4786287 0.2369269];
xi=[-0.9061798 -0.538469 0 0.538469 0.9061798];
%m=[1 1 0;1 2 0;0 0 3];
%c=[1 0 0;0 0 1;0 1 0];
%k1=[2 1 0;1 3 0;0 0 4];
%F=[2;4;6];
M=[2 1];
K=[4 2 2];
dk=[0 0 0];
C=[0 0 1];
F=[0;10];

%[m k1 c]=arryf(M,K,C,n);
kt=zeros(n-1);
t=0;
a=pi/6;
bb=pi/6;
%w=2^0.5+(5^0.5-2^0.5)/2;%w(rad/s)
%w=0;
w=3^0.5;
tf=60;
h=0.028;
%h=Tin/10;
N=20;
N1=20;
dt=h/2^N;
v=zeros(2*n+1,1);
v(1,1)=t;
vk=diag(eye(2*n))*0;
%vk(1:2,1)=10/2;
o1=zeros(n,1);

F0=[o1;F];
%[Hx Hn]=eig(H);
kn=0;
for i=1:tf/h
t(:,i)=(i-1)*h;
v(1,i)=t(:,i);
%door=(1+cos(w*t(:,i)))/2;
oo=w*t(:,i);
if w>0

   
    if oo<=2*kn*pi+0.5*pi-a&oo>=2*kn*pi

        door=1;
    elseif oo<=2*kn*pi+0.5*pi+a&oo>2*kn*pi+0.5*pi-a

        door=0.5*(1+cos((0.5*(oo-0.5*pi+a)/a)*pi));
    elseif oo<=2*kn*pi+3*pi/2-a&oo>2*kn*pi+0.5*pi+a

        door=0;
    elseif oo<=2*kn*pi+3*pi/2+a&oo>2*kn*pi+3*pi/2-a

        door=0.5*(1-cos((0.5*(oo-3*pi/2+a)/a)*pi));
    %elseif oo>2*k*pi+3*pi/2+a&oo<=2*pi+2*k*pi
    elseif 2*kn*pi+3*pi/2+a<oo<=2*pi+2*kn*pi
         door=1;
    end
door1(:,i)=door;
else 
    door=0;
end
kt=K-door*dk;
[m c k]=arryf(M,C,kt,n);
H=[-inv(m)*c/2 inv(m);0.25*c*inv(m)*c-k -0.5*c*inv(m)];
[Hx Hn]=eig(H);
    I=eye(size(H));
 Ta=H*dt+(H*dt)^2*(I+(H*dt)/3+(H*dt)^2/12+(H*dt)^3/60)/2;%泰勒展开高阶项
  for j=1:N%求总Ta
    Ta=2*Ta+Ta*Ta;
  end
  T=I+Ta;
v(2:2*n+1,i)=vk(:);%给定初值
vf=0;
    for ii=1:5
        h1=h*(1-xi(ii))/2;
        dt1=h1/2^N1;
       Ta1=H*dt1+(H*dt1)^2*(I+(H*dt1)/3+(H*dt1)^2/12+(H*dt1)^3/60)/2;
       for j=1:N1%求总Ta1
    Ta1=2*Ta1+Ta1*Ta1;
  end
  T1=I+Ta1;
  %vf=vf+we(ii)*T1*F0;
vf=vf+we(ii)*T1*F0*cos(w*(t(:,i)+0.5*h+0.5*h*xi(ii)));
end
vk=T*vk+0.5*h*vf;    
if oo>2*(kn+1)*pi&w>0
    kn=kn+1;
end
end
 % PIM end
%v21=v;
 save('sjjl','v','t','h','tf');
 figure(1);
plot(t,v(2,:));
title('一质量振动时域波形图');
xlabel('时间(s)');
ylabel('振幅');
 figure(2);
plot(t,v(3,:));
title('一质量振动时域波形图');
xlabel('时间(s)');
ylabel('振幅');
if w>0
figure(4);
plot(t,door1);
end
%figure(2);
%plot(t,v(3,:));
%figure(3);
%plot(t,v(4,:));