Determination of the operating point and the enthalpy per unit surface of a cold battery with icy water and a double heat exchanger

The cold battery is a heat exchanger between two fluids, air (secondary fluid) and iced water (primary fluid).The cold battery is composed of two heat exchangers in series, one of which is made up of flat-plate in galvanized steel serving as a reservoir for the iced water and the other one a copper shelland-tube exchanger with aluminum cooling blades. The two heat exchangers are connected to a pipe of the same diameter. These pipes will permit the transit of the icy water coming from the flat-plate heat exchanger by gravitation towards the tubes of the second exchanger [1]. The good operation of this cold battery depends on the knowledge of its operating point. We are proposing a technique of determination of the operating point by using one of the two fluids (water or air) and the efficiencies [2, 3].The Knowledge of that operating point will enable us, through experimental means, determine the mean surface temperatureand then determine the mean surface enthalpy from the specific heat capacity at saturation obtained from the linearization of the entrance and exit air temperatures on the saturation curves.