function 
 
 
   qrloss = regsim(var) 
 
 
   % Evaluate the effectiveness and performance of the regenerator 
 
 
   % Israel Urieli, 7/23/2002 - Modified 2/15/2010 
 
 
   % modified 11/27/2010 to include 'no regenerator matrix' 
 
 
   % Arguments: 
 
 
   %   var(22,37) array of variable values every 10 degrees (0 - 360) 
 
 
   % Returned value: 
 
 
   %   qrloss - regenerator net enthalpy loss [J] 
 
 
   % Row indices of the var, array 
 
 
   TC = 1; 
 
 
   % Compression space temperature (K) 
 
 
   TE = 2; 
 
 
   % Expansion space temperature (K) 
 
 
   QK = 3; 
 
 
   % Heat transferred to the cooler (J) 
 
 
   QR = 4; 
 
 
   % Heat transferred to the regenerator (J) 
 
 
   QH = 5; 
 
 
   % Heat transferred to the heater (J) 
 
 
   WC = 6; 
 
 
   % Work done by the compression space (J) 
 
 
   WE = 7; 
 
 
   % Work done by the expansion space (J) 
 
 
   W  = 8; 
 
 
   % Total work done (WC + WE) (J) 
 
 
   P  = 9; 
 
 
   % Pressure (Pa) 
 
 
   VC = 10; 
 
 
   % Compression space volume (m^3) 
 
 
   VE = 11; 
 
 
   % Expansion space volume (m^3) 
 
 
   MC = 12; 
 
 
   % Mass of gas in the compression space (kg) 
 
 
   MK = 13; 
 
 
   % Mass of gas in the cooler (kg) 
 
 
   MR = 14; 
 
 
   % Mass of gas in the regenerator (kg) 
 
 
   MH = 15; 
 
 
   % Mass of gas in the heater (kg) 
 
 
   ME = 16; 
 
 
   % Mass of gas in the expansion space (kg) 
 
 
   TCK = 17; 
 
 
   % Conditional temperature compression space / cooler (K) 
 
 
   THE = 18; 
 
 
   % Conditional temeprature heater / expansion space (K) 
 
 
   GACK = 19; 
 
 
   % Conditional mass flow compression space / cooler (kg/rad) 
 
 
   GAKR = 20; 
 
 
   % Conditional mass flow cooler / regenerator (kg/rad) 
 
 
   GARH = 21; 
 
 
   % Conditional mass flow regenerator / heater (kg/rad) 
 
 
   GAHE = 22; 
 
 
   % Conditional mass flow heater / expansion space (kg/rad) 
 
 
   global 
 
 
   matrix_type 
 
 
   % m)esh or f)oil 
 
 
   global 
 
 
   ar 
 
 
   % regen internal free flow area [m^2] 
 
 
   global 
 
 
   awgr 
 
 
   % regen internal wetted area [m^2] 
 
 
   global 
 
 
   dr 
 
 
   % regen hydraulic diameter [m] 
 
 
   global 
 
 
   tr 
 
 
   % regen temperature [K] 
 
 
   global 
 
 
   freq omega 
 
 
   % cycle frequency [herz], [rads/s] 
 
 
   % Reynolds number over the cycle 
 
 
   for 
 
 
   (i = 1:1:37) 
 
 
   gar(i) = (var(GAKR,i) + var(GARH,i))*omega/2; 
 
 
   gr = gar(i)/ar; 
 
 
   [mu,kgas,re(i)] = reynum(tr,gr,dr); 
 
 
   end 
 
 
   % average and maximum Reynolds number 
 
 
   sumre = 0; 
 
 
   remax = re(1); 
 
 
   for 
 
 
   (i = 1:1:36) 
 
 
   sumre = sumre + re(i); 
 
 
   if 
 
 
   (re(i) > remax) 
 
 
   remax = re(i); 
 
 
   end 
 
 
   end 
 
 
   reavg = sumre/36; 
 
 
   % Stanton number, number of transfer units, regenerator effectiveness 
 
 
   if 
 
 
   (strncmp(matrix_type, 
 
 
   'm' 
 
 
   ,1)) 
 
 
   [st,fr] = matrixfr(reavg); 
 
 
   elseif 
 
 
   (strncmp(matrix_type, 
 
 
   'f' 
 
 
   ,1)) 
 
 
   [st,ht,fr] = foilfr(dr,mu,reavg); 
 
 
   elseif 
 
 
   (strncmp(matrix_type, 
 
 
   'n' 
 
 
   ,1)) 
 
 
   [st,ht,fr] = foilfr(dr,mu,reavg); 
 
 
   end 
 
 
   ntu = st*awgr/(2*ar); 
 
 
   effect = ntu/(ntu + 1); 
 
 
   % Calculate qrloss 
 
 
   for 
 
 
   (i=1:1:37) 
 
 
   qreg(i) = var(QR,i); 
 
 
   end 
 
 
   qrmin = min(qreg); 
 
 
   qrmax = max(qreg); 
 
 
   qrloss = (1 - effect)*(qrmax - qrmin); 
 
 
   % Regenerator simple analysis results: 
 
 
   fprintf( 
 
 
   '============ Regenerator Simple analysis =============\n' 
 
 
   ) 
 
 
   fprintf( 
 
 
   'Average Reynolds number: %.1f\n' 
 
 
   , reavg); 
 
 
   fprintf( 
 
 
   'Maximum Reynolds number: %.1f\n' 
 
 
   , remax); 
 
 
   fprintf( 
 
 
   'Stanton number(Average Re): %.3f\n' 
 
 
   ,st); 
 
 
   fprintf( 
 
 
   'Number of transfer units: %.1f\n' 
 
 
   ,ntu); 
 
 
   fprintf( 
 
 
   'Regenerator effectiveness : %.3f\n' 
 
 
   ,effect); 
 
 
   fprintf( 
 
 
   'Regenerator net enthalpy loss: %.1f[W]\n' 
 
 
   , qrloss*freq);