program htcoef c c John Mahaffy, Penn State University, CmpSc 201 Example c 1/26/96 c implicit none real k,D,Pr,h,Nulam,Nuturb real Re1,Re2,Re3,Re4 c c Calculate an approximation for heat transfer coefficients c in a 1 inch pipe for several different Reynolds numbers c c An example of why you should learn to use subprograms c c h - heat transfer coefficient ( w/m**2/K)' c Nulam - laminar Nusselt number c Nuturb - Turbulent Nusselt number (Dittus-Boelter correlation) c k - conductivity ( w/m/K)' c D - hydraulic diameter (m) c Re - Reynolds number c Pr - Prandl number c data k,D,Pr/0.617,0.0254,1.0/, Nulam/4.0/ c c Each of the following blocks assigns a Reynolds number, calculates c an associated Turbulent Nusselt number and calculates the heat c transfer coefficient based on the maximum of Turbulent and Laminar c Nusselt Numbers c Re1=10. Nuturb=0.023*Re1**0.8*Pr**0.4 h=k/D*max(Nulam,Nuturb) print *, 'For Reynolds Number = ',Re1 print *, 'Heat Transfer Coefficient is ',h,' w/m**2/K' c Re2=100. Nuturb=0.023*Re2**0.8*Pr**0.4 h=k/D*max(Nulam,Nuturb) print *, 'For Reynolds Number = ',Re2 print *, 'Heat Transfer Coefficient is ',h,' w/m**2/K' c Re3=1000. Nuturb=0.023*Re3**0.8*Pr**0.4 h=k/D*max(Nulam,Nuturb) print *, 'For Reynolds Number = ',Re3 print *, 'Heat Transfer Coefficient is ',h,' w/m**2/K' c Re4=10000. Nuturb=0.023*Re4**0.8*Pr**0.4 h=k/D*max(Nulam,Nuturb) print *, 'For Reynolds Number = ',Re4 print *, 'Heat Transfer Coefficient is ',h,' w/m**2/K' c stop end