Counterflow heat exchanger

Fig. 2. Fluid temperature profiles in (a) a parallel flow heat exchanger and (b) a counterflow heat exchanger. Terms are defined in text.

A similar derivation can be made for a siagle-pass counterflow heat exchanger ia which the hot and cold fluids ate flowing ia the opposite direction (see Fig. 2b). The resultiag heat-transfer equation is still... 

The equations for counterflow ate identical to equations for parallel flow except for the definitions of the terminal temperature differences. Counterflow heat exchangers ate much mote efficient, ie, these requite less area, than the parallel flow heat exchangers. Thus the counterflow heat exchangers ate always preferred ia practice. 

Fig. 3. Extreme cases of counterflow heat exchangers having infinite surface area (a) Cf and (b) Cf C. Terms are defined ia text.

The expressions for S can be obtained usiag basic governing heat-transfer equations, such as equations 14 and 19 with proper substitutions of equation 36. For simple, siagle-pass, parallel- and counterflow heat exchangers, the foUowiag expressions result ... 

Figure 3. Terminal temperatures in a counterflow heat exchanger.

Counterflow Heat Exchanger and the Heat Exchanger Effectiveness... 

In a counterflow or countercurrent heat exchanger, hot and cold fluids enter the exchanger from opposite sides. The counterflow heat exchanger in Fig. 9.5 serves as a reference for all other heat exchanger configurations. A detailed analysis of this type of heat exchanger is therefore necessary. 

This heat exchanger effectiveness is one of the important parameters that describes the performance of a counterflow heat exchanger. 

In Fig. 9.6 the temperature profiles in a counterflow heat exchanger are shown when C/, >. ... 

FIGURE 9.6 Counterflow heat exchanger temperature profiles when... 

Horlock, J.H. (1998), The relationship between effectiveness and exergy loss in counterflow heat exchangers, ASME Paper 1998-GT-32. 

In this section, we will describe the various types of mechanical coolers with reference to their working cycles. We shall start with a brief description of counterflow heat exchangers. This subject will be further dealt in Chapter 6 when treating dilution refrigerators. 

This cycle also uses continuous counterflow heat exchanger and is closely related to the Joule-Thomson and Claude cycles as shown in Fig. 5.15(a) [60], The cryocooling or reverse Brayton cycle derives from a reciprocating gas engine patented by G. B. Brayton in... 

Fig. 6.6. Scheme of a counterflow heat exchanger for dilution refrigerator. 

Process diagram of shell-and-tube counterflow heat exchanger. Key At1 = T1 — t1 cold-end temperature difference At2 = T2 — t2 warm-end temperature difference. 

Countercurrent flow capillary electrophoresis, 4 635 Countercurrent packed tower, 25 810, 811 Countercurrent shaft kilns, 15 47-48 Counterdiffusion, 1 41-42 equimolar, 1 39-40 Counterflow heat exchangers... 

Single-pass counterflow heat exchanger, heat- transfer equation for, 13 251 Single-pass heat exchangers, heat-exchanger effectiveness for, 13 254 Single-photon emission computed... 

Fig. 3. Extreme cases of counterflow heat exchangers having infinite surface area...

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