Gas flows through orifices and short tubes have been extensively studied from the 1960s through the 1980s for both fundamental and practical reasons. These flows are a basic and often important element of various modern gas driven instruments. Recent advances in micro- and nanoscale technologies have paved the way for a generation of miniaturized devices in various application areas, from clinical analyses to biochemical detection to aerospace propulsion. The latter ...
Flow through circular orifices with thickness-to-diameter ratios varying from 0.015 to 1.2 is studied experimentally and numerically with kinetic and continuum approaches. Helium and nitrogen gases are used in the range of Reynolds numbers from 0.02 to over 700. Good agreement between experimental and numerical results is observed for mass flow and thrust corrected for the experimental facility background pressure. For thick-to-thin orifice ratios of mass flow and thrust vs ...
Hypersonic chemically reacting flow around a wedge in the near-continuum regime was numerically studied by the DSMC method with the main goal of validation of real gas effect models. The influence of vibration-dissociation coupling on the results of numerical simulations was analyzed. To this end, two models of chemical reactions were used in the computations, the total collisional energy model and a vibrationally favored model. The numerical results were compared ...