Page 379 - Design and Operation of Heat Exchangers and their Networks

362 Design and operation of heat exchangers and their networks

0.5
= 4.0 1.0
0.4
0.3 NTU 0.5

0.2 0.3
0.1
0.1
q 0.0
2
-0.1

-0.2
-0.3
-0.4
-0.5
0 1 2 3 4 5 6 7 8 9 10 11 12
(A) τ
1.0

0.8 0.3
0.6 NTU = 0.1 0.5
0.4 1.0
4.0
0.2

q 0.0
1
-0.2
-0.4
-0.6
-0.8

-1.0
0 1 2 3 4 5 6 7 8 9 10 11 12
(B) τ
Fig. 7.5 Exit responses to a shell-side sinusoidal inlet temperature change of a 1–3 heat
exchanger with stream entrances at opposite ends. (A) Shell-side fluid and (B) tube-
side fluid.