This work presents a full three dimensional finite element multi-physics simulation of the conjugate heat transfer for a gas sensing device composed by a two-element array of Ultra Low Power (ULP) Metal Oxide Semiconductor (MOX) sensors operated in a miniaturized sampling chamber. The heat equation in a solid, the Poisson equation for the electric potential and the incompressible Navier-Stokes and energy equations for a fluid have been solved in a coupled manner. Validation of the simulation results has been performed comparing the power dissipated by the array with a set of experimental data under different operating conditions. Good agreement between the simulations and the experiments has been obtained. A small effect on the power dissipated by the sensor, in presence of volumetric fluxes in the sampling chamber, has been observed both numerically and experimentally.
28 Oct 2007
SENSORS, 2007 IEEE