Heat transfer in paraffin oil/water emulsion involving supercooling phenomenon

An emulsion of a mixture of alkane in water has been elaborated for thermal energy storage and transport. Investigations on heat transfer inside a sample of the emulsion in an agitated tank during a cooling phase are presented. The variation of the temperature as a function of time shows a stabilisation of temperature below the melting temperature which is interpreted as a supercooling phenomenon. The results are found in good agreement with experimental data obtained by using a calorimetric method. A theoretical expression is proposed to simulate the thermal behaviour which permits predicting the duration of the plateau of crystallisation. The results compare very well with experimental data, thus giving a new impulse to the design of new complex fluids for both storage and heat transport. (C) 2001 Elsevier Science Ltd. All rights reserved.