THERMOACOUSTIC WAVES IN PULSED PIRANI SENSOR MEMS. NUMERICAL INVESTIGATION

The transient heat transfer process and generated thermoacoustic waves are studied in rarefied gas confined between two stationary concentric cylinders. The inner cylinder (filament) is subjected to a periodically heating-cooling cycle. The heat transfer is modeled with continuous model based on Navier-Sockes Fourier equations of motion and energy transfer and with a statistical DSMC model. The temperature, thermodynamic pressure and pressure difference between thermodynamic pressure and radial stress tensor component are investigated for different forced circular frequencies of heating cooling cycle of filament and for different filament radii. The numerical results  for pressure variation at the end of any local heating stage of heating-cooling cycle are close to the value of equilibrium thermodynamic pressure. The results are applicable in designing the pulsed Pirani sensors.