Page 357 - Defrosting for Air Source Heat Pump

Appendices 353

swatertray=zeros(45,3); % the total mass of water flowing away from
the water collecting tray in the 5 seconds, kg
s_qr2=zeros(45,3); % the energy taken in the refrigerant, J
hro=zeros(45,3); % the enthalpy value of output refrigerant, kJ/kg
% list the unknown parameters, and initialize these parameters with
zeroes

for i=1:3 % three circuits in this study based on the experiment
results
for j=1:18 % about 18*5 seconds in the first two stages, obtained
from the experimental results
if j==1
khri=hri(j,i); % , kJ/kg
kMr=Mr(j,i); % kg / s
kTri=Tri(j,1); % °C
2
kRr=Rr(j,i); %(K˙m )/W
ksmrw=0.0001; % the total retained water at the beginning is
0 kg, choose 0.0001 as the value for debugging, kg
kTw1=0.01; % the temperature of the melted frost at the begin-
ning is 0 °C, choose 0 °C as the value for debugging
% all the input parameters in the function listed here
x0=[0.0001 0.0001 0.01 1200 0.001]; % mf=x(1), mrw=x(2),
Tw=x(3); qr=x(4); Tro=x(5) the values of debugging
options=optimset(’display’,’off’,’MaxIter’,100000,
’MaxFunEvals’,20000); % number
[A,fval,exit]=fsolve(@(x)mystage1(x,ksmrw,kTw1,i,kRr,kTri,
khri,kMr),x0,options); % x, ksmrw, kTw1, i, kTri, kRr, kqr
mf(j,i)=A(1); % the mass of melted frost, kg/s
mrw(j,i)=A(2); % the mass of retained water, kg/s
Tw(j,i)=A(3); % the temperature of retained water, °C
qr(j,i)=A(4); % the energy used in defrosting from refrigerant, W
Tro(j,i)=A(5); % the temperature of tube surface at exit of each
circuit, °C
A;
x00=real(A);
fval
exit
qm(j,i)=334000*mf(j,i); % W
sfrost(j,i)=5*sum(mf(:,i)); % kg
mvaw(j,i)=0; % kg/s
smvaw(j,i)=5*sum(mvaw(:,i)); % kg
qvap(j,i)=mvaw(j,i)*2443*1000; % J
s_qvap(j,i)=sum(qvap(:,i))*5; % J
watertray(j,i)=0; % kg/s
swatertray(j,i)=sum(watertray(:,i)); % kg