Coker A.K. Fortran Programs for Chemical Process Design, Analysis, and Simulation
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Heat Transfer 677
(1) The time required to heat the agitated batch using the double pipe
countercurrent exchanger can be determined from Equation 8-170.
In
T~-_tt)_(K
6 -
u M
1)( WbWhCh
)0
K6W hC h
-- WbC
where
( /
- expJUA[ 1
K 6
WbC
')}
WhC h
WbC -- (50,000)(0.48)
= 24,000
WhC h -- (12,000)(0.60)
= 7,200
{ / '
K 6 -
exp (50 x 400) 24,000
7,200
= 0.143
ln(400 - 100) ) - (0" 143 - 13( (50' 000)(12' 000) )400 - 300 59,000
ln(400- 100))- (0.143- 1)( (50,000)(12,000)(0;6_)0/0
400 - 350 59,000 ((Jli~43i(;7, 200) - 24,
0 - 7.87 hr
(2) Equation 8-177 applies for the time to heat the agitated batch using
a 1-2 exchanger.
(T'-t' / /S'Wb /0
In TI i~ - M
(8-177)
and
678
Fortran Programs for Chemical Process Design
S m
2(K 7 - 1)
KT{R + 1+
(i2--~ -- l) 0"5 } -{R --i t- l-(i2--1 - 1) 0.5 }
where
UA
K 7 -- exp
WbC
(R 2 +
1) 0.5 }
and
(8-178)
R m
WbC
WhC h
24,000
7,200
= 3.33
- exp~ (50)(400)
K7
/
24,000
(3.332 + 1) 0.5 }
= 18.127
Substituting the value of
K 7
into Equation 8-178 gives,
S
2(18.127 - 1)
18.127{3.33+1+(3.332 + 1)~
1--(3.332 + 1) 0.5 }
= 0.2435
The value of S in Equation 8-177 gives
in(400-100)) (0.2435x50,000)
400 - 3-~ - 59~b00 0
0 - 8.68 hr
(3) Equations 8-177, 8-179, and 8-180 apply for the time to heat the
agitated batch using a 2-4 exchanger.
2(Ks- 1){1 + [(1- S)(1- RS)] ~ }
S - (8-179)
(K 8 - 1)(R + 1)+ (K 8
+ 1)(R 2 -t-
1) 0.5
Heat Transfer
679
and
K 8 -exP{2wbcUA
(R2+
1)o.5}
(8-180)
Equation 8-179 is an implicit equation involving S on both sides, and
can be solved by trial and error until an equality is reached. Rearranging
Equation 8-179 gives
LHS RHS
S{(K 8 - 1)(R + 1)+ (U 8 + 1)(8 2 + 1) 0.5 }
= 2(K s - 1){1 + [(1- S)(1- RS)] ~
(8-181)
{/ 5ox4oo
K 8-exp 2x5Oi000x0.48
3.332+1)~
= 4.2576
R- 3.33
Substituting S- 0.262 in Equation 8-177 gives
in(400-100))_(0-262x50,000)
400- 350 59. 0-0-0 0
0 - 8.07 hr
Table 8-28
S LHR RHS
0.260 8.418 8.566
0.261 8.45 8.539
0.262 8.588 8.573
0.263 8.515 8.485
680
Fortran Programs for Chemical Process Design
References
1. Cheremisinoff, N. P., Heat Transfer Pocket Handbook, Houston,
Gulf Publishing Company, 1984.
2. Bowan, R. A., A. C. Mueller, and W. M. Nagle, Mean Temperature
Difference in Design, Trans. A.S.M.E., May 1940, pp. 283-293.
3. Kern, D. Q., Process Heat Transfer, McGraw-Hill Co., New York,
1950.
4. Shah, R. K., E C. Subbarao, and R. A. Mashelkar, Heat Transfer
Equipment Design, Hemisphere Publishing Corporation, New York,
1988.
5. Chisholm, D. (Ed.), Developments in Heat Exchanger Technology,
1, Applied Science Publishers Ltd., London, 1980.
6. Donohue, D. A., Heat Exchanger Design, Petroleum Refiner, Vol. 34,
No. 11, Nov., 1955, pp. 175-184.
7. Morton, D. S., Thermal Design of Heat Exchangers, Industrial And
Engineering Chemistry, Vol. 52, No. 6, June, 1960, pp. 474-478.
8. Lord, R. C., P. E. Minton, and R. P. Slusser, "Design of Heat
Exchangers," Chem. Eng., Jan. 26, 1970, pp. 96-118.
9. Gulley, D. L., "Use Computers to Select Exchangers," Petroleum
Refine, Vol. 39; No. 7, July 1960, pp. 149-156.
10. Polley, G. T., M. H. Panjeh-Shahi, and M. Picon Nunez, "Rapid Design
Algorithms For Shell and Tube and Compact Heat Exchangers,"
Trans. IChemE, Vol. 69, Part A, Nov. 1991, pp. 435-445.
11. S ieder, E. N., and G. E. Tate, "Heat Transfer and Pressure Drop of
Liquids in Tubes," Ind., Eng. Chem., Vol. 28, No. 12, Dec. 1936,
pp. 1429-1435.
12. Hedrick, P. E., "Calculate Heat Transfer For Tubes In the Transition
Region," Chem. Eng., June 1990, p. 147.
13. Frank, O., "In Practical Aspects of Heat Transfer," Proc. of 1976
Fall Lecture Series of New Jersey- North Jersey Sections of AIChE.,
A.I. ChE., New York, 1976, pp. 1-25.
14. Sandler, H. H. and E. T., Luckiewicz, "Practical Process Engineer-
ing~A Working Approach To Plant Design," McGraw-Hill Book
Company, New York, 1987.
15. Wilson, R. E., W. H. McAdams, and M. Seltzer, "The Flow of Flu-
ids Through Commercial Pipe Lines," The Journal of Ind. and Eng.
Chem., Vol. 14, No. 2, Feb. 1922, pp. 105-119.
16. Cook, E. M., "Rating Methods for Selection of Air Cooled Heat
Exchangers," Chem. Eng., August 3, 1964, pp. 97-104.
Heat Transfer 681
17. Ganapathy, V., "Process Design Criteria," Chem. Eng., March 27,
1978, pp. 112-119.
18. Smith, E. C., "Air-Cooled Heat Exchangers," Chem. Eng., Nov. 17,
1958, pp. 145-150.
19. Brown, R., "A Procedure for Preliminary Estimates," Chem. Eng.,
March 27, 1978, pp. 108-111.
20. Blackwell, W. W., Chemical Process Design On A Programmable
Calculator, McGraw-Hill Book Company, New York, 1984.
Chopey, N. E and Hicks, T. G., Handbook, of Chemical Engineer-
ing Calculations, McGraw-Hill Book Company, New York, 1984.
22. Lam, V. and Sandberg, C., "Choose the Right Heat Tracing Sys-
tem," Chem. Eng. Prog. March, 1992, pp. 63-67.
23. Kohli, I. E, "Steam Tracing of Pipelines," Chem. Eng., March 26,
1979, p. 163.
24. McAdams, W. H., Heat Transmission, 3rd Ed., McGraw-Hill, New
York, 1954, p. 179.
25. Bondy, F. and S. Lippa, "Heat Transfer in agitated vessels," Chem.
Eng., April, 1983, pp. 62-71.
21.
PROGRAM PROG81
THIS PROGRAM CALCULATES THE CORRECTED L.M.T.D. IN SHELL-AND-TUBE
HEAT EXCHANGERS
THE PROGRAM CALCULATES:
i. THE IDEAL AND TRUE MEAN TEMPERATURE DIFFERENCE FOR ONE
OR MORE EXCHANGER IN SERIES.
2. THE PROGRAM WILL INCREASE THE NUMBER OF EXCHANGER SHELL
UNTIL A 'REASONABLE' F-FACTOR IS OBTAINED THUS ELIMINATING
THE NEED FOR THE CHARTS AND GRAPHS NORMALLY USED TO CALCULATE
F-FACTORS FOR SHELL-AND-TUBE HEAT EXCHANGERS.
THE PROGRAM IS BASED ON THE FOLLOWING ASSUMPTIONS:
i. THE HOT AND COLD FLUIDS FLOW COUNTERCURRENT TO EACH OTHER.
2. THE OVERALL HEAT TRANSFER COEFFICIENT (U) IS CONSTANT
THROUGHOUT THE HEAT EXCHANGER.
3. THE FLOW RATE OF EACH FLUID IS CONSTANT.
4. THE SPECIFIC HEAT OF EACH FLUID IS CONSTANT.
5. THERE IS NO CONDENSATION OF VAPOR OR BOILING OF LIQUID
IN ANY PART OF THE EXCHANGER.
6. HEAT LOSSES ARE NEGLIGIBLE.
7. THERE IS EQUAL HEAT TRANSFER SURFACE IN EACH PASS.
8.
THE TEMPERATURE OF THE SHELL-SIDE FLUID IN ANY SHELL-SIDE
PASS IS UNIFORM OVER ANY CROSS-SECTION.
THI = HOT FLUID INLET TEMPERATURE, oF.
TH2 = HOT FLUID OUTLET TEMPERATURE, oF.
TCI = COLD FLUID INLET TEMPERATURE, oF.
TC2 = COLD FLUID OUTLET TEMPERATURE, oF.
N = NUMBER OF SERIES EXCHANGER SHELLS REQUIRED.
LMTD = LOG MEAN TEMPERATURE DIFFERENCE.
F = CORRECTION FACTOR.
DELTI = TH2-TCI, oF.
DELT2 = THI-TC2, oF.
DELT = LMTD.
REAL LMTD, N
OPEN (UNIT=3, FILE='DATA81.DAT', STATUS='OLD', ERR=I8)
OPEN (UNIT=l, FILE='PRN')
READ THE HOT FLUID INLET TEMPERATURE, oF: THI
READ THE HOT FLUID OUTLET TEMPERATURE, oF: TH2
READ THE COLD FLUID INLET TEMPERATURE, oF: TCI
READ THE COLD FLUID OUTLET TEMPERATURE, oF: TC2
READ THE INITIAL NUMBER OF SERIES EXCHANGER SHELLS REQUIRED: N
READ (3, *, ERR=I9) THI, TH2
READ (3, *, ERR=I9) TCl, TC2
READ (3, *, ERR=I9) N
GO TO i0
682
18
i00
19
ii0
i0
120
130
140
150
160
15
30
25
WRITE (*, i00)
FORMAT (6X, 'DATA FILE DOES NOT EXIST')
GO TO 999
WRITE (*, ii0)
FORMAT (6X, 'ERROR MESSAGE IN THE DATA VALUE')
GO TO 999
WRITE (i, 120)
FORMAT (///,10X,'THE CORRECTED LMTD IN A SHELL AND TUBE HEAT',\)
WRITE (i, 130)
FORMAT ( ' EXCHANGER',/IH , 78(IH*) )
WRITE (I, 140) TH1, TH2
FORMAT(6X,'HOT FLUID INLET TEMPERATURE, oF:', T60, F9.3,/,6X,
'HOT FLUID OUTLET TEMPERATURE, oF:',T60, F9.3)
WRITE (I, 150) TCl, TC2
FORMAT(6X,'COLD FLUID INLET TEMPERATURE, oF:',T60, F9.3,/,6X,
'COLD FLUID OUTLET TEMPERATURE, oF:', T60, F9.3)
WRITE (i, 160) N
FORMAT(6X,'NUMBER OF SERIES EXCHANGER SHELLS:',T60,F4.0)
P = (TC2-TCI)/(THI-TCI)
R = (THI-TH2)/(TC2-TCI)
RSQRT = (R*'2+I.)**0.5
IF (R .EQ. 1.0) THEN
GO TO 25
ELSE
VALI = 1.0-((P*R-I.0)/(P-I.0))**(I./N)
VAL2 = R-((P*R-I.0)/(P-I.0))**(I./N)
P1 = VALI/VAL2
ENDIF
VAL3 = (2.0/PI)-I.0-R+RSQRT
VAL4 = (2.0/PI)-I.0-R-RSQRT
A = VAL3/VAL4
IF
( A .LT.
0.0) THEN
GO TO 30
ELSE
VAL5 = (RSQRT/(R-I.0))*ALOG((I.0-PI)/(I.0-PI*R))
F = VAL5/ALOG(A)
ENDIF
GO TO 40
N = N+I
GO TO 15
P2 = P/(N-P*(N-I.))
VAL6 = (2.0/P2)-2.0+RSQRT
683
40
45
50
C
55
170
180
999
VAL7 = (2.0/P2)-2.0-RSQRT
B = VAL6/VAL7
IF
(B .LT.
0.0) THEN
GO TO 30
ELSE
VAL8 = (RSQRT*P2)/(I.0-P2)
F = VAL8/ALOG(B)
ENDIF
IF ( F .GT. 0.75) THEN
GO TO 45
ELSE
N =
N+I
GO TO 15
ENDIF
DELTI = THI-TC2
DELT2 = TH2-TCI
IF (DELTI .EQ. DELT2) THEN
GO TO 50
ELSE
CALCULATE THE LOG MEAN TEMPERATURE DIFFERENCE
LMTD = (DELTI-DELT2)/ALOG(DELTI/DELT2)
ENDIF
GO TO 55
DELT = LMTD
CALCULATE THE CORRECTED LOG MEAN TEMPERATURE DIFFERENCE
CLMTD = F*LMTD
WRITE (I, 170) N, F, LMTD, CLMTD
FORMAT (6X,'THE NUMBER OF SHELLS REQUIRED:',T60, F4.0,/,6X,
'THE F- FACTOR:',T60, F8.4,/,6X,
'THE LOG MEAN TEMPERATURE DIFFERENCE,oF:',T60,F8.4,/,6X,
'THE CORRECTED LMTD, oF:',T60, F8.4)
WRITE (i, 180)
FORMAT (IH ,78(IH-))
FORM FEED THE PRINTING PAPER TO TOP OF THE NEXT PAGE.
WRITE (i, *) CHAR(12)
CLOSE (3,STATUS='KEEP')
CLOSE (i)
STOP
END
684
PROGRAM PROG82
*************************************************************
THIS PROGRAM RATES A SHELL AND TUBE HEAT EXCHANGER WITH
EITHER A SINGLE SHELL PASS AND ANY MULTIPLE OF TWO TUBE
PASSES OR TWO OR MORE SHELL PASSES.
THE PROGRAM ASSUMES THAT THERE IS NO CHANGE OF PHASE.
THE PROGRAM USES DEVELOPED CORRELATIONS FOR FRICTION FACTORS
IN BOTH THE SHELL AND TUBE SIDES. HEDRICK'S CORRELATION
(Chem. Eng. June, 1990) FOR ESTIMATING THE HEAT TRANSFER
COEFFICIENT FOR TUBES IN THE TRANSITION REGION IS EMPLOYED
IN THE PROGRAH.
************************************************************
NOMENCLATURE: TUBE SIDE
i. FLUID TYPE = FTS
2. NUMBER OF TUBES = NT
3. TUBE INSIDE DIA., inch = TID
4. TUBE OUTSIDE DIA., inch = TOD
5. TUBE PITCH, inch = TP
6. PITCH TYPE (TRIANGLE/SQUARE) = T/S
7. TUBE LENGTH, ft. = TL
8. NUMBER OF PASSES = TNP
9. FOULING FACTOR = TFF
I0. INLET TEMPERATURE, oF = TTI
ii. OUTLET TEMPERATURE, oF = TT2
12. SPECIFIC HEAT CAPACITY (Btu/iboF) = TSHC
13. VISCOSITY, cP = TVIS
14. DENSITY, ib/ft^3. = TDEN
15. FLUID THERMAL CONDUCTIVITY, (Btu/ft.h.oF)= TFK
16. MASS FLOWRATE, ib/hr. = TW
NOMENCLATURE: SHELL SIDE
i. FLUID TYPE = FSS
2. NUMBER OF SHELL PASSES = NS
3. SHELL INSIDE DIA., inch = SID
4. NUMBER OF BAFFLES = NB
5. BAFFLE SPACING, inch = BSP
6. FOULING FACTOR = SFF
7. INLET TEMPERATURE, oF = TSI
8. OUTLET TEMPERATURE, oF = TS2
9. SPECIFIC HEAT CAPACITY, (Btu/ib.oF) = SSHC
I0. VISCOSITY, cP = SVIS
ii. DENSITY, ib/ft.^3 = SDEN
12. FLUID THERMAL CONDUCTIVITY, (Btu/ft.h.oF)= SFK
13. MASS FLOWRATE, ib/hr. = SW
PARAMETER (PI = 3.1415927, G=32.174)
CHARACTER*30 FTS,FSS
CHARACTER TYPE
COMMON/TUBE1/ FTS, TYPE
COMMON/TUBE2/ NT, TID, TOD, TP, TL, TNP
685
ii
12
COMMON/TUBE3/ TFF, TTI, TT2, TSHC, TVIS, TDEN
COMMON/TUBE4/ TFK, TW
COMMON/TUBE5/ RET, PRT, TFRF, HT, TV
COMMON/TUBE6/ TDELP, TRDELP, TOTDP
COMMON/SHELL1/ FSS
COMMON/SHELL2/ NS, SID, NB, BSP, SFF
COMMON/SHELL3/ TSI, TS2, SSHC, SVIS, SDEN
COMMON/SHELL4/ SFK, SW
COMMON~SHELL5~
RES, PRS, SFRF, HS, SV
COMMON/SHELL6/ SDELP
COMMON/OUT/ Q, AREA, F, LMTD, U, QI, CMTD
REAL NT, NS, NB, LMTD
OPEN (UNIT = 3, FILE='DATA82.DAT', STATUS='OLD', ERR= 18)
OPEN (UNIT = i, FILE='PRN ' )
READ THE TUBE SIDE HEAT EXCHANGER PA/tAMETERS
READ THE FLUID TYPE: FTS
READ (3, ii, ERR=I9) FTS
FORMAT (A)
READ THE NUMBER OF TUBES: NT
READ THE TUBE INSIDE DIAMETER, inch: TID
READ THE TUBE OUTSIDE DIAMETER, inch: TOD
READ THE TUBE PITCH, inch: TP
READ THE TYPE OF PITCH (TRIANGULAR: T) or (SQUARE: S): TYPE
READ (3, *, ERR=Ig) NT, TID, TOD, TP
READ ( 3, 12, ERR=I9) TYPE
FORMAT (A)
READ THE TUBE LENGTH, ft.: TL
READ THE NUMBER OF PASSES: TNP
READ THE TUBE SIDE FOULING FACTOR: TFF
READ THE INLET TEMPERATURE, oF: TTI
READ THE OUTLET TEMPERATURE, oF: TT2
READ THE SPECIFIC HEAT CAPACITY OF FLUID, (Btu/ib.oF): TSHC
READ THE FLUID VISCOSITY, cP: TVIS
READ THE FLUID DENSITY, ib/ft^3: TDEN
READ THE FLUID THERMAL CONDUCTIVITY, Btu/hr.ft.oF.: TFK
READ THE FLUID FLOWP~TE, ib/hr.: TW
READ (3, *
READ (3, *
READ (3, *
, ERR=I9) TL, TNP, TFF, TTI
, ERR=I9) TT2, TSHC, TVIS, TDEN
, ERR=I9) TFK, TW
READ THE SHELL SIDE HEAT EXCHANGER PARAMETERS
READ THE FLUID TYPE: FSS
686