Structure of Flow Fields in Low Pressure Impactor
In order to clarify the detailed flow fields of impinging jets in a low pressure impactor, nitrogen and argon flow fields are investigated experimentally and numerically at a relatively small range of P<SUB>down</SUB>/P<SUB>up</SUB>, where P<SUB>down</SUB> is the downstream stagnation pressure and P<SUB>up</SUB> the upstream stagnation pressure. The pressure at the center of collection plate, P<SUB>c</SUB> is measured in addition to the flow visualization by Laser Induced Fluorescence (LIF) technique, which is used in previous study. Furthermore, the flow fields in a low pressure impactor have been simulated by solving the axisymmetric Euler equation through Harten-Yee TVD method. The effects of P<SUB>down</SUB>/P<SUB>up</SUB> and H/D on flow fields are examined in detail, where H is the jet-to-plate distance and D the nozzle diameter. The calculated shock wave position on jet axis and the pressure at the center of collection plate are in reasonable agreement with the experimental results. It is found that the structure of flow fields changes drastically at a certain value of P<SUB>down</SUB>/P<SUB>up</SUB> and there exist hysteresis phenomena in the relationship between the value of P<SUB>c</SUB>/P<SUB>up</SUB> and that of P<SUB>down</SUB>/P<SUB>up</SUB> for both gases. The formation of the separation bubble at a certain value of H/D is discussed.
- Journal of nuclear science and technology
Journal of nuclear science and technology 35(11), 788-795, 1998-11-25
Atomic Energy Society of Japan