Economically optimal dimensioning of a counterflow and crossflow heat exchanger for free cooling

During the cold seasons, it is possible to use ambient air to cool down the coolants in air-conditioning or other refrigeration applications. Applying this free cooling reduces the energy costs of a refrigeration machine. This paper presents a general method for the economically optimal dimensioning of a free cooling system in which a heat exchanger of the counterflow or crossflow type is applied to the heat transfer between the ambient air and the coolant.