git.gag.com Git - debian/openrocket/blob - core/doc/techdoc/figures/drag/skinfriction.m

   1 Rlam = 10.^(4:0.05:7);
   2 Rturb = 10.^(4:0.05:8);
   3
   4 Rcrit = 539154;
   5 Rtrans = 10.^(5:0.05:8);
   6 Rtrans = [Rcrit Rtrans(find(Rtrans > Rcrit))];
   7
   8 Rs=3e-6;
   9 Lr=1.0;
  10 Rcrit=[51*(Rs/Lr)^(-1.039) 1e8];
  11 critical = 0.032*(Rs/Lr)^(0.2) * [1 1];
  12 Rcrit
  13
  14 laminar = 1.328./sqrt(Rlam);
  15 turbulent = 1./(1.50*log(Rturb)-5.6).^2;
  16 transitional = 1./((1.50*log(Rtrans)-5.6).^2) - 1700./Rtrans;
  17
  18 figure;
  19
  20 loglog(Rlam,laminar,'k-.',Rturb,turbulent,'k--',Rtrans,transitional,'k:',Rcrit,critical,'k-');
  21 axis([1e4 1e8 0.0005 0.02]);
  22 xlabel('Reynolds number');
  23 ylabel('Skin friction coefficient');
  24 legend('Laminar','Turbulent','Transitional','Roughness-limited');
  25
  26 set(gcf, 'PaperPositionMode', 'manual');
  27 set(gcf, 'PaperUnits', 'centimeters');
  28 set(gcf, 'PaperPosition', [2 2 15 7.5]);
  29
  30 print('skinfriction.eps');