extra slides lmtd
DESCRIPTION
Heat Exchangers, LMTDTRANSCRIPT
TT
TC,in dAH,in C,out
H,out C,in H C
1 1ln T T
U AT T mCp mCp
TH TC
TH,inTH,out
TC
H H,in H,out C C,out C,in
H,in H,out C,out C,in
H C
1 1 and
mCp T T Q mCp T T
T T T TmCp Q mCp Q
TC,outQx
H H H C C C dH mCp dT Q mCp dT dH
H,in C,outH,in H
H,out C,in
ln T T A U T TT T Q
,out C,out C,inT T
H CH C
H C
and
QdA Q U T T dAU T T
Q QdT dTmCp mCp
LM
H,in C,out H,out C,in
Q QAU T
T T T TU
H C
H C H CH C
H C
1 1
mCp mCp
U T T dA U T T dAdT dT
mCp mCp
dT dT
H,in C,out
H,out C,in
lnT TT T
H C
H C H C
H C
1 1
1
dT dT U dAT T mCp mCp
d T TU
T T
H,in C,out 1T T A
dAmCp mCp
H,in C,out H,out C,in 1 2LM
H,in C,out 1
2H,out C,in
lnln
T T T T T TTT T T
TT T
H CT TH,out C,in H C0
H CSolved analytically if , , are constant
T T mCp mCp
mCp mCp U
TLM is also referred to as LMTD