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The aim of this work is to develop a simple optical method for the visualization of the natural convection flow generated in an electronic system during its normal operation. The presented experimental set-up allows to reveal local refractive index changes in a phase objects. A fringe pattern is acquired, through the cooling fluid under analysis, with a digital camera two times: the first one with the fluid at rest, the second one with the thermal load due to the electronic device normal operation. By the means of the MATLAB processing of the acquired images it’s possible to reveal the shape and the directions of the thermal flow lines for the cooling fluid. In this way we can obtain a deeper understanding of the optimal convection working volume or information for the optimization of the relative spatial positioning of the several electronic components in a complex electronic system, like a printed circuit board (PCB). The proposed technique has been tested on two typical heat extraction situations recurrent in the electronic devices. In this paper are presented the experimental results of the visualization of the convective flow, in air, for an heat sink and a power resistor.
We investigate the bias-induced insulator-metal transition in organic electronics devices, on the basis of the Su-Schrieffer-Heeger model combined with the non-equilibrium Greens function formalism. The insulator-metal transition is explained with th
Light absorption in conducting materials produces heating of their conduction electrons, followed by relaxation into phonons within picoseconds, and subsequent diffusion into the surrounding media over longer timescales. This conventional picture of
We numerically study the Rayleigh-Benard (RB) convection in two-dimensional model emulsions confined between two parallel walls at fixed temperatures. The systems under study are heterogeneous, with finite-size droplets dispersed in a continuous phas
We explore, theoretically and experimentally, a method for cooling a broadband heat reservoir, via its laser-assisted collisions with two-level atoms followed by their fluorescence. This method is shown to be advantageous compared to existing laser-c
Using the finite volume CFD software FLUENT, one fan was studied at a given flow rate (1.5m3/min) for three different operational rotating speeds : 2,000, 2,350 and 2,700 rpm. The turbulent air flow analysis predicts the acoustic behavior of the fan.