PROGRAM H3SS2 C... C... H3 - HEAT CONDUCTION IN A CIRCULAR FIN, STEADY STATE C... SOLUTION, VERSION 2 C... C... DOUBLE PRECISION CODING IS USED IMPLICIT DOUBLE PRECISION(A-H,O-Z) C... C... COMMON AREA WITH PROBLEM PARAMETERS PARAMETER(NR=6) COMMON/P/ ALPHA, BETA, UA, U0, U(NR), + DR, R0, R1, R(NR), B, + RHOCP C... C... OPEN AN OUTPUT FILE NO=6 OPEN(NO,FILE='OUTPUT', STATUS='UNKNOWN') C... C... PROBLEM PARAMETERS C... C... FIN INSIDE RADIUS R0=0.5D0 C... C... FIN OUTSIDE RADIUS R1=2.0D0 C... C... FIN THICKNESS B=0.2D0 C... C... HEAT TRANSFER COEFFICIENT H=0.01D0 C... C... RHO*CP RHOCP=2.0D0 C... C... THERMAL DIFFUSIVITY ALPHA=0.01D0 C... C... AMBIENT TEMPERATURE UA=25.0D0 C... C... INSIDE TEMPERATURE U0=150.0D0 C... C... RECIPROCAL TIME FOR HEAT TRANSFER BETA=(2.0D0*H)/(B*RHOCP) C... C... INCREMENT FOR RADIAL GRID DR=(R1-R0)/DFLOAT(NR-1) C... C... RADIAL GRID DO 1 I=1,NR R(I)=R0+DFLOAT(I-1)*DR 1 CONTINUE C... C... STEADY STATE SOLUTION WITH DIRICHLET BOUNDARY CONDITION C... C... CONSTANT X0 X0=DSQRT(BETA/ALPHA)*R0 X1=DSQRT(BETA/ALPHA)*R1 C... C... EVALUATE THE SOLUTION AT A SERIES OF RADIAL POSITIONS DO 2 I=1,NR X=DSQRT(BETA/ALPHA)*R(I) C... C... ANALYTICAL SOLUTION U(I)=DSQRT(X0/X)*DSINH(X1-X)/DSINH(X1-X0) C... C... CONVERSION FROM DIMENSIONLESS TO DIMENSIONAL TEMPERATURE U(I)=UA+(U0-UA)*U(I) 2 CONTINUE C... C... PRINT THE SOLUTION WRITE(NO,3)(R(I),I=1,NR),(U(I),I=1,NR) 3 FORMAT(/,' Dirichlet boundary conditions',/, + ' r ',6F9.2,/,' u(r) ',6F9.3,/) STOP END DOUBLE PRECISION FUNCTION DFLOAT(I) C... C... FUNCTION DFLOAT CONVERTS A SINGLE PRECISION INTEGER INTO A C... DOUBLE PRECISION FLOATING POINT. THIS FUNCTION IS PROVIDED C... IN CASE THE USER'S FORTRAN COMPILER DOES NOT INCLUDE DFLOAT. C... DFLOAT=DBLE(FLOAT(I)) RETURN END