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TRADITIONAL PLATE EXCHANGER CALCULATION

Number of plates 100 (101) [-]

Plate Length 8.000 [m]Plate Width 0.00 [m]

Plate !hi"#ness 0.00$ [m]

%ot and &old gap 0.008 [m]

%ot 'ater temperature .1 []

&old 'ater temperature $*.1 []

%ot and &old fluid mass flo' +00.0 [#g,s]

%ot and &old fouling resistan"e 0.0000 [m$W,]

Plate metal "ondu"tiit 0 [W,m,]

Water properties are ta#en at aerage temperatures. /s the hot and "old inlet temperatures are 80

and $0 degrees &entigrade respe"tiel the aerage temperature is 0 degree &. !he film"orre"tion for the heat transfer "oeffi"ient is negle"ted for the hand "al"ulation. t is small and of

opposite influen"e at ea"h pro"ess side.

%eat e2"hanging /rea /3h2 4 8.000 5 0.00 5 100 4 +00 [m$]

Nr of hot and "old "hannels N3"h 4 0 [-]

/3flo',"hannel /3f"h 4 0.008 5 0. 4 0.00+ [m$]

&hannel &ir"umferen"e &3f"h 4 $ 5 (0.008 6 0.) 4 1.017 [m]

%drauli" iameter 3hd 4 + 5 /3f"h , &3f"h 4 0.019+8 [m]:lo' /rea per fluid /3flo' 4 N3"h 5 /3f"h 4 0.$ [m$]

:luid ;ass 0 deg.& u3' 4 0.000$ [Pa.s]

Water "ondu"tiit > 0 deg & #3' 4 0.7+ [W,m,]

?enolds ?e 4 = 5 , u3' 4 *** [-]

Prandtl 'ater > 0 deg & Pr 4 . [-]

%ot @ &old heat transfer "oeffi"ient A3' 4 0.0$ 5 #3',3hdr 5 ?eB0.8 5 PrB0.+

4109$ [W,m$,]

Plate resistan"e , m$ ?3pl 4 thi"#ness,"ond 4 0.00$ , 0 4 0.0000+ [m$W,]

!otal heat transfer resistan"e ,

m$

?3t 4 $,A3' 6 $ 5 ?3foul 6 ?3pl 4

?3t 4 $,109$ 6 $50.0000 6 0.0000+ 40.000$8

[m$W,]

Cerall %eat transfer &oeffi"ient A3oa 4 1 , ?3t 4 00+.7 [W,m$,]

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No' the oerall heat transfer "oeffi"ient is "al"ulated. We hae the follo'ing eDuationsE

F3transferred 4 delta3!3mean 5 A3oa 5 /3h2 (eD.1)

F3fluid 4 delta3!3fluid 5 ;3flo' 5 &p3fluid (eD.$)

Ge"ause the fluid and the fluid mass flo' are identi"al on both sides delta3!3mean eDuals theinitial temperature differen"e (!4!3hotin-!3"oldin) minus the delta3!3fluid orE

delta3!3mean 4 ! - delta3!3fluid (eD.)

nserting this into (eD.1) eDuating (eD.1) and (eD.$) 'e getE

(! - delta3!3fluid) 5 A3oa 5 /3h2 4 delta3!3fluid 5 ;3flo' 5 &p3fluid (eD.+)

Holing for delta3!3fluid E

delta3!3fluid 4 ! 5 A3oa5/3h2 , (A3oa5/3h2 6 ;3flo'5&p3fluid) (eD.)

delta3!3fluid 4 70.0 5 00+.75+00.0 , (00+.75+00.0 6 +00.05+0) 4 $.71 []

Q_fluid = M_flow * Cp * delta_T_fluid = 400.0 * 4035 * 25.61 = 41334540 [W], o 41.33

[MW]

!his results inE

outlet temperature of 80 - $.71 4 +.* degree &entigrade (hot side)

outlet temperature of $0 - $.71 4 +.71 degree &entigrade ("old side)

!he results of /%!L are

.+1 degree & (hot side)++.7+ degree & ("old side)

%eat transferredE +1.17 [;W]

The hand calculation is 0.4 in e!!o!. It is inte!estin" to ins#ect the out#ut o$ AHTL.

The e%ect o$ &a!'in" (uid #!o#e!ties on heat t!ans$e! is si"ni)cant. O&e!all e%ects

on heat t!ans$e! cancel out to "!eat e*tent. Ho+e&e!, the e%ect on -etal

te-#e!atu!es is -uch "!eate!. The hot inlet side #late te-#e!atu!es should ' at

a!ound the a&e!a"e o$ hot (o+ inlet/ and cold (o+ outlet te-#e!atu!es, i.e. 0. 1

230.0 44.546 7 58.98 de"!ee C. A&e!a"e #late te-#e!atu!e calculated ' AHTL atthis location is 59.:;< de"!ee C.

This e*a-#le is e*ceedin"l' si-#le, ut in -o!e co-#le* cases, +ith #hase

t!ansitions and $o! technicall' di=cult #!ole-s it #a's to ha&e a solution that is as

accu!ate as #ossile.

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