Thermoacoustic waves in pulsed Pirani gauge. Frequency analysis

The transient heat transfer process is studied in rarefied gas argon (Ar) confined between two stationary concentric cylinders. The inner cylinder (filament) is subjected to a periodically heating-cooling cycle. The energy transfer is modeled with continuous model based on Navier-Stokes-Fourier equations of motion and energy transfer and with a statistical Direct Simulation Monte Carlo model. Numerically is analyzed the operation of the Micro Mechanical-Electro System (MEMS) pulsating Pirani gauge at the real-time frequencies. The actual read pressure (pressure difference) variation is studied. The results can be used to analyze the pulsating Pirani gauge sensitivity, i.e., the time to reach sustained oscillations as well as to adjust the pressure reading to the actual value.