Solving non linear 2nd order differential equation

4 vues (au cours des 30 derniers jours)
Reuben Salisbury
Reuben Salisbury le 7 Avr 2020
I am trying to solve the differential equation:
mx''+cx'+kx=ky+cy''
y is the input and x is the output.
y=Y0sin(wt)
where m=100, c=1300, k= 17000, Y0=input value, w=input value
initially I need to solve this, and then i need to plot displacement and velocity profiles.
clear
t=0:0.1:15; %time peroid
Y0= input('wave amplitude ') ; %Wave amplitude
l= input('length of wave ') ; %length of the wave
u=input('speed of boat'); %Boat Velocity
w=u/l; %frequency of wave
y=Y0*sin(w*t); %wave height model
Dr=0.5; %Required Damping Ratio
k=17000; %Spring Constant of suspension
m=100;
wn=(k/m)^0.5; %Natural Frequency
wd=wn*(1-Dr^2)^0.5; %Damped Natural Frequency
c=2*Dr*(k*m)^(0.5); %Damping coefficient
syms x(t)
ode=m*diff(x,t,2)+c*diff(x,t)+k*x==y+(2*Dr/wn)*diff(y,t);
xSol(t)=dsolve(ode);

Réponse acceptée

Birdman
Birdman le 7 Avr 2020
Try this:
clear
syms t
Y0= input('wave amplitude ') ; %Wave amplitude
l= input('length of wave ') ; %length of the wave
u=input('speed of boat'); %Boat Velocity
w=u/l; %frequency of wave
y=Y0*sin(w*t); %wave height model
Dr=0.5; %Required Damping Ratio
k=17000; %Spring Constant of suspension
m=100;
wn=(k/m)^0.5; %Natural Frequency
wd=wn*(1-Dr^2)^0.5; %Damped Natural Frequency
c=2*Dr*(k*m)^(0.5); %Damping coefficient
syms x(t)
Dx(t)=diff(x,t);
ode=m*diff(x,t,2)+c*diff(x,t)+k*x==y+(2*Dr/wn)*diff(y,t);
xSol(t)=dsolve(ode,[x(0)==0 Dx(0)==0]);%displacement
DxSol(t)=diff(xSol,t);%velocity
t=0:0.05:15;
plot(t,xSol(t),t,DxSol(t))

Plus de réponses (0)

Catégories

En savoir plus sur Numerical Integration and Differential Equations dans Help Center et File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by