Introduction

Abstract

Any apparatus which facilitates the exchange of heat between two fluids may be classified as a heat exchanger. The diversity of the applications in which heat exchanging apparatus are utilised covers an extensive range of equipment/ varying in technological sophistication and size from domestic radiators and refrigerators, through aircraft and motor vehicle engines, to chemical processing plant. As a consequence, many different forms of heat exchangers have been developed. These are usually categorised as either recuperators or regenerators depending upon the process by which the heat exchange between the two heat transfer fluids is achieved. In recuperators the two heat transfer fluids simultaneously flow across the opposing surfaces of a solid interface, and the heat exchange occurs through this interface. A typical example is the radiator used in water cooled internal combustion engines? this device effects the transfer of heat from water circulating within its interior to air streaming across its exterior. Thus, recuperative heat exchangers facilitate a continuous exchange of heat. In contrast, in regenerators the heat transfer process is of a periodic nature.