Sd. Kolev et al., Thermal modelling of a porous silicon-based pellistor-type catalytic flammable gas sensor with two supporting beams, MICROELEC J, 31(5), 2000, pp. 339-342
A three-dimensional transient thermal mathematical model of a porous silico
n based pellistor with two supporting beams was developed. The model was nu
merically solved using the implicit alternating-direction finite difference
method. A computer program written in ANSI C and run on a VAX/VMS computer
was utilised to study the influence of the power consumption and the main
geometrical dimensions (membrane, beam and heater size) of the pellistor me
ntioned above on its transient and steady-state thermal behaviour. It was f
ound that considerable improvement in the thermal behaviour of the pellisto
r could be achieved by reducing the membrane size (length and width). The o
ptimal beam length was determined as 100 mu m. By comparing the main source
s of energy dissipation it was found that energy was lost predominantly thr
ough the heat conduction into the supporting beams. (C) 2000 Elsevier Scien
ce Ltd. All rights reserved.