ode45 solve and taking current state as input

Hi

Can anyone help me how to fix this problem?

my questions are blow:

this is my function to be solved:

function dx = CSmacro_derive(x,fluid_params,dQ,dV,h_in,dm_in,dm_out)

dx=zeros(3,1);
v=x(1)/x(2);
h=fluid_params.h;                                               
P=fluid_params.P;                                               

dx(1)=dV;
dx(2)=dm_in-dm_out;
dx(3)=(1/(x(2)*fluid_params.dudT))*...
        (dQ+((h_in-h)*dm_in)+(P+fluid_params.dudv)*(v*dx(2)-dx(1)));
end

This my main script:

t=linspace(0,10,10);
dV =0.1*sin(t);
dm_in=0.5;
dm_out=0;
% Initial condition
V=0.3326;
m=1;
T=15 + Kel;
x0=[V;m;T];

% Upstream refrigerant
v_in = 0.3326;
T_in = 15 + Kel;

fluid_in = refprop(v_in,T_in,r410a);
h_in=fluid_in.h;


[~,~,dQ] = convecCool(theta_a,x(3),convec_params);
fluid_params = CSmacro_props(x,r410a);

%this is my question.
%how can I take the current x value as my input to these two functions.
for i=length(t)
  dx = @(t,x) CSmacro_derive(x,fluid_params,dQ,dV(i),h_in,dm_in,dm_out);
  opts=odeset('RelTol',1e-6);
  [t,x] = ode45(dx,t,x0,opts);
end

Thanks!

[Torsten]

By calling "convecCool" and "CSmacro_props" from "CSmacro_derive"

[WANYI ZHANG]

Can you write a little bit detailed codes?

Thanks a lot

[Torsten]

Put the lines marked in bold after the line

function dx = CSmacro_derive(x,fluid_params,dQ,dV,h_in,dm_in,dm_out)

and remove fluid_params,dQ from the list of passed parameters (because they are recalculated now in "CSmacro_derive" for the actual x-vector):

function dx = CSmacro_derive(x,dV,h_in,dm_in,dm_out)

[WANYI ZHANG]

I fixed it.

but my dV is not passing properly.

Do you know why?

[Torsten]

You changed

dx = @(t,x) CSmacro_derive(x,fluid_params,dQ,dV(i),h_in,dm_in,dm_out);

to

dx = @(t,x) CSmacro_derive(x,dV(i),h_in,dm_in,dm_out);

?

[Jan]

I've formatted the code as code to improve the readability. Please do this by your own in future posts. Thank you.