undefined function of variable

changsu namgung

2019 3 16

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8 次查看（30 天）

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"a person is considered "alive" if the mean temperature along the profile is greater than 22 degrees Celsius."

i gotta be able to show above line into my function. AND my output of function is only T (a vector of the temperature along the entire profile of the head), and aliveFlag (a flag either equal to 1 or 0 depending on whether the person is alive or dead, respectively).

How can i find mean temperature as mentioned in the above line?

if you have any questions regard to my problem, feel free to comment! thanks

% Spatial (r) parameters
L      = 0.12;                      % Size of the domain
rstart = 0;                         % Start of computational domain (m)
rend   = L;                         % End of computational domain (m)
nr     = 101;                       % Number of grid points along the radius vector
dr     = (rend-rstart)/(nr-1);      % Spatial step size, delta r (m)
r      = rstart:dr:rend;            % Vector of grid points in r
% Temporal (t) parameters 
timestart = 0;                      % Starting time (0 seconds)
dt        = (timeend-timestart)/(nr-1);  % Temporal step size, delta t (s)
time      = timestart:dt:timeend;        % Vector of times
% Phyiscal parameters
T1    = -41;                        % Temperature at r=0
T2    = 37;                         % Temperature at r=L
A     = T2-T1;                      % Amplitude of the saw tooth wave
k     = 0.527;                      % Thermal conductivity (W/m-K)
rho   = 1000;                       % Density (kg/m^3)
gamma = 3600;                       % Heat capacity (J/kg-K)
c     = sqrt(k/(rho*gamma));        % Heat equation constant                
% Calculate B coefficients using a for loop
nfs = 1000;               % Number of fourier terms               
B = zeros(1,nfs);         % Initialise B vector   
lambda=zeros(1,nfs);      % Initialise lambda vector
for n = 1:nfs;           
    B(n)=(2*A)/(n*pi);                   % Calculate B coefficients
    lambda(n)=(n*pi*c)/L;
end
%% Solve for T using three for loops in time, space, and Fourier series
% Loop through time
for i = 1:nt               % For each time
    
    t = time(i);           % time in seconds
    
    % Vector of zeros to initialise the Fourier series solution.
    % This should be re-initialised at each new time step.
    T = zeros(1,nr); 
    
    % Loop through space
    for j = 1:nr;          % For each grid point        
        T(j) = (78*r(j))/L-41;         % Add the steady state solution
        
        % Loop through the Fourier series
        for n = 1:nfs;
            % Calculate series sum for T at r(j) and t
            p=(n*pi)/L;
            T(j)    = T(j)+(156/(n*pi))*sin(n*pi*r(j)/L)*exp(-1*p^2*c^2*t);              
        end
    end
end