Thermochimica Acta 448 (2006) 123–129 DSC study and computer modelling of the melting process in ice slurry T. Kousksou ∗ , A. Jamil, Y. Zeraouli, J.-P. Dumas Laboratoire de Thermique ´ Energ´ etique et Proc´ ed´ es, Avenue de l’Universit´ e, BP 1155, 64013 Pau Cedex, France Received 6 March 2006; received in revised form 26 June 2006; accepted 12 July 2006 Available online 18 July 2006 Abstract In order to understand the non-isothermal melting kinetics in the ice slurry, a differential scanning calorimetry (DSC) was used. Experimental results were compared to those obtained by a numerical simulation in which a general enthalpy method was applied. In this work the ice slurry studied consists of ice particles uniformly dispersed within a water–antifreeze liquid mixture. The effects of the heating rate and the initial antifreeze mass fraction are discussed. It has been found that the temperature gradients inside the sample of the solution become important if either heating rate increases or initial antifreeze mass fraction decreases. © 2006 Elsevier B.V. All rights reserved. Keywords: Heat transfer; Ice/water–ethanol; Ice slurry; DSC; Simulation 1. Introduction Nowadays, considerable work for the development on the ice–liquid mixtures (or ice slurries) is under way in many coun- tries [1]. The ice slurry studied consists of ice particles uniformly dispersed within a water–antifreeze liquid mixture. The main benefit of using ice slurry is the latent heat of ice or enthalpy difference at melting [2,3]. Ice slurries have several times higher heat transport capability than single-phase fluids. Due to this and its more complex behaviour, ice slurry is sometimes referred to as advanced secondary fluid. Because of its good thermophysical and technological char- acteristics, ethanol–water solution is one of the most studied mixture. In the literature [4–7] there is a great information on the diphasic properties. For design and performance evaluation of a thermal storage system using ice slurry, it is necessary to understand the behavior of the ice slurry during the phase change process. The issue of heat transfer during melting of ice in ice slurries has been a subject for several papers. Their review is given in Refs. [8,2]. In these works, special attention has been paid to the determination of the values of heat transfer coefficients. The aim of the present contribution is to investigate, exper- imentally and numerically, the kinetics of the melting of ice ∗ Corresponding author. E-mail address: Tarik.kousksou@univ-pau.fr (T. Kousksou). slurry in the small container by using the differential scanning calorimetry (DSC). The influences of both initial antifreeze mass fraction and heating rate were investigated. 2. Binary phase diagram The phase diagram of the aqueous binary solution of ethanol [9] is presented in Fig. 1. In our application, the eutectic point and over-eutectic part are not of interest, because the ice slurry is available in the tem- peratures range from just below 0 to -20 ◦ C. The ice mass fraction is calculated from the melting tem- perature T of the binary mixture solution, which is a func- tion of the ethanol mass fraction W a in the residual liquid solution: T = T (W a ) (1) Once the initial mass fraction of ethanol in the binary mixture solution before freezing W a,i and the temperature are known, the equilibrium ice mass fraction is calculated with: W ic (T ) = 1 - W a,i W a (T ) (2) in which W a (T ) is found from the liquidus curve, the inverse of Eq. (1). 0040-6031/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.tca.2006.07.004