Page 358 - Defrosting for Air Source Heat Pump
P. 358

354                                                          Appendices

               hro(j,i)=44518+1170.36*Tro(j,i)+1.68674*Tro(j,i)^2+5.2703/
            1000*Tro(j,i)^3;
               qr2(j,i)=kMr*(khri-hro(j,i)); % W
               s_qr2(j,i)=sum(qr2(:,i))*5; % W
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

             else if j<8
                 khri=hri(j,i); % , kJ/kg
                 kMr=Mr(j,i); % kg/s
                 kTri=Tri(j,i); %, °C
                                    2
                 kRr=Rr(j,i); % (K˙m )/W
                 ksmrw=sfrost(j-1,i); % the total retained water on 5*j
            seconds is the summate value of 0-5*(j-1)seconds
                 kTw1=Tw(j-1,i); % the temperature of the melted frost on 5*j
            seconds
                 % 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 for 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
                                    2
                  hair(j,i)=0; % W/(m °C)
                 qair(j,i)=0; % W
                 s_qair(j,i)=sum(qair(:,i))*5; % W
                                  2
                  hd(j,i)=0; % W/(m °C)
                 qvap(j,i)=mvaw(j,i)*2443*1000; % W
                 s_qvap(j,i)=sum(qvap(:,i))*5; % W
                 watertray(j,i)=0; % kg/s
                 swatertray(j,i)=sum(watertray(:,i)); % kg
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