Hello! I am modeling a cryogenic liquid spill in order to predict evaporation rate, pool mass accumulation, pool temperature, and pool radius. I incorporated a spill time (tspill) in addition to an overall run time to represent the time it takes until some can shut off the spill/leak. However, if this tspill is 10 seconds and I run the program anything more than maybe 40 seconds, it gets stuck calculating imaginary numbers in one of my for loops. I want to be able to stop the ODE integration before it begins calculating imaginary numbers. I have located this instance which is when either the mass term or radius term becomes less than zero.
I tried using these two formats to stop the integration:
function[value,isterminal,direction] = spillmodel1(t,Y)
value = [Y(1)<0; Y(2); Y(3)<0; Y(4)];
isterminal = 1;
direction = 0;
M=Y(1);
Tpool=Y(2);
r=Y(3);
Evap = Y(4);
I think I struggle here to set the value terms to identify imaginary numbers.
And this when I call the function:
opts = odeset('Events',@spillmodel1);
[t,y]=ode45(@spillmodel1, tspan, yo, opts);
When I do this the code runs but it calculates incorrect data for all 4 y terms (they increase expontentially which is wrong). If i take this format out, it calculates correctly but the imaginary numbers are present in the data.
I will attach the code as it runs properly under certain conditions (run time less than 40 seconds, appropriate spill rate) without the ode stop integration formatting. If anyone can identify the error in my ode stop integration format please let me know.
Thank you.
