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Geankoplis 4th ed. 4.5‐4. Water flowing at a rate of 13.85 kg/s is to be heated from 54.5 to 87.8oC in a double‐pipe heat exchanger by 54,430 kg/h of hot gas flowing counterflow and entering at 427oC ( 1.005 / ).
Algebraic expressions for the correction factor Fhave been developed for vari- ous shell-and-tube and cross-flow heat exchanger configurations [1–3], and the results may be represented graphically. Selected results are shown in Figures 11S.1 through 11S.4 for common heat exchanger configurations.
A heat exchanger is a component that allows the transfer of heat from one fluid (liquid or gas) to another fluid. Reasons for heat transfer include the following:
Heat • The temperature difference determines the direction of heat transfer. • Bodies don’t “contain” heat; heat always refers to energy in transit from one body to another. • We can change the temperature of a body by adding heat to it.
The natural laws of physics always allow the driving energy in a system to flow until equilibrium is reached. Heat leaves the warmer body or the hottest fluid, as long as there is a temperature difference, and will be transferred to the cold medium. A heat exchanger follows this principle in its endeavour to reach equalisation.
The basic thermal design theory for recuperators is presented in Chapter 3, advanced design theory for recuperators in Chapter 4, and thermal design theory for regenerators in Chapter 5. Pressure drop analysis is presented in Chapter 6.
Abstract. This chapter provides an overview of how different heat exchanger types, prob-lems, and networks are analyzed. Heat exchangers are categorized by shape, flow arrangement, area to volume ratio, and channel size. The problem type depends on what information is available and what is sought.
