Enhancement of heat transfer in chaotic heat exchangers

Some experimental devices may offer the possibility to enhance both heat transfer and flow mixing. In many applications, flows are in laminar regime which disadvantages transport phenomena. To enhancetransport properties it is usual to distinguish two types of techniques,passive or active. We present two heat exchangers based on a passive technique. Two different coil heat exchangers utilizing chaotic advection to enhance heat and mass transfer were experimentally studied. The coils were plunged inside a container filled with water. A water flow in laminar regime with Reynolds numbers varying between150 and 2300 was circulating inside the coil. Heat transfer coefficientsbetween the coil and the tank water were measured and the Nusselt numbers were deduced. Pressure drops also were measured. Anenergetic criterion was used allowing us to choose the best geometry

Keywords:

Heat transfer , Chaotic advection , Enhancement techniques , Energy efficiency