Flexible Polymeric Hollow Fiber Heat Exchangers

Abstract

Polymeric hollow fiber heat exchangers were proposed about a decade ago as an alternative to metal exchangers for low temperature application. Flexible polymeric hollow fiber heat exchangers were prepared and tested for liquid / air and liquid / liquid conditions. These heat exchangers use a plastic capillary with an outer diameter of 0.5 -1.3 mm and a wall thickness of about 10% of the outer diameter. These heat exchangers are flexible and can be used in narrow slots and shaped channels. In experiments we obtained overall heat-transfer coefficients in water/air applications of up to 900 W/m 2 K. These heat exchangers are effective even in natural convection application where the advantage of high heat transfer coefficient on micro surfaces is utilized. The use of plastic and non-corrosive materials is advantageous in applications where the weight of the heat exchanger is important (about 50% reduction in weight in comparison to classical metal products) and in difficult chemical environments. The paper presents the results of laboratory tests of the developed prototypes of polymeric hollow fiber heat transfer surfaces for various applications.