Hi @aziz
I suggest that you run the simulation of the compressor equation in MATLAB. If it works in MATLAB, it is generally easier to migrate the MATLAB code to the Simulink environment. With MATLAB code, you have almost complete control over the solution.
In Simulink, if you are not using the code migration approach, you will need to construct multiple blocks to perform the necessary mathematical operations described in the compressor equation. Without a basis for verifying the results, you may feel compelled to "trust" that the Simulink blocks are 100% accurate. However, if you have the MATLAB simulation results, you can always make a comparison.
Here is a sample code:
%% equations of the system
function dx = DifferentialEquation(t, x)
dx = zeros(2, 1);
dx(1) = (- 3.5 - 1.5*sin(x(1)))*x(1) - 4*x(2);
dx(2) = ( 9.5 - 10.5*sin(x(1)))*x(1) - 2*x(2);
end
%% run the simulation
tspan = [0, 3];
x0 = [1; 0];
[t, x] = ode45(@DifferentialEquation, tspan, x0);
%% plot results
plot(t, x), grid on
xlabel('t'), ylabel('\bf{x}(t)')
