Heat transfer enhancement

Heat transfer enhancement is the process of increasing the effectiveness of heat exchangers. This can be achieved when the heat transfer power of a given device is increased or when the pressure losses generated by the device are reduced. A variety of techniques can be applied to this effect, including generating strong secondary flows or increasing boundary layer turbulence. Heat transfer enhancement is the process of increasing the effectiveness of heat exchangers. This can be achieved when the heat transfer power of a given device is increased or when the pressure losses generated by the device are reduced. A variety of techniques can be applied to this effect, including generating strong secondary flows or increasing boundary layer turbulence. During the earliest attempts to enhance heat transfer, plain (or smooth) surfaced were used. This surface requires a special surface geometry able to provide higher h A {displaystyle {hA}} values per unit surface area in comparison with a plain surface. The ratio of h A {displaystyle {hA}} of an enhanced heat transfer surface to the plain surface is called Enhancement Ratio ' E h {displaystyle E_{h}} '. Thus,