In the present work, the purpose is to study heat exchange which is directly related to factors such as Reynolds number, thermal properties of materials, geometric shapes and dimensions. A numerical study of the heat exchanges between crosssections selected of a mini-channel cooler of dimensions (40 × 52 × 6 mm3) is carried out. Three different forms have been considered for cooling an electronic component using a nanofluid (CuO-water) as a cooling liquid with 4% volume concentration of nanoparticles. The simulation is carried out using the ANSYS Fluent software. The Reynolds number (Re) is taken between 100 and 700 and the stream regime is assumed to be stationary. The results obtained for the three forms of mini-channels proposed show that the raise in the exchange surface between the CuO-water nanofluid and walls of the mini-channels leads to the increase in the heat exchange coefficient and to the amelioration of the maximum temperature of electronic components by increasing the value of the flow velocity. This is confirmed by the results of the third case. In contrast to the first case that does not contain ribs, and the second case, which contains two ribs inside the channel, these two cases provide insufficient heat exchange, and the maximum temperature of the electronic component remains high compared to the third case, which contains four ribs, the latter contribute to the increase in heat exchange inside the channel.