**ABSTRACT**

The present study is the three-dimensional simulation of cooling control of electronic component, by natural convection and mixed convection in a cubical enclosure, filled with air. The heating square portion similar to the integrated electronic device and releasing a constant flux is placed on the right vertical wall of the enclosure. The same wall has, in its upper part, an extractor, while the rest of the considered wall is adiabatic. Its opposite wall has an opening maintained at a cold temperature. For low temperatures, the cooling of the component is provided by natural convection, however, in the case of strong temperature gradients, the extractor, operating at variable velocity, allows the evacuation of the dissipated heat. The cooling control of the component, the temperature distribution as well as the flow of fluid in the cavity is studied according to the governing parameters, namely the Rayleigh number, Ra and Reynolds number Re. The obtained results show that the control cooling of the electronic components has a great industrial interest compared to the continuous cooling (ventilation), by an optimal choice of the governing parameters and the material constituting the components.

**KEYWORDS**

PAPER SUBMITTED: 2019-05-08

PAPER REVISED: 2020-05-22

PAPER ACCEPTED: 2020-05-24

PUBLISHED ONLINE: 2020-06-07

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