Toshihiro Morioka

Effect of Inlet Diameter on the Discharge Coefficients of Toroidal-Throat Critical-Flow Venturi Nozzles

The effect of the inlet diameter Din on the discharge coefficient Cd of critical-flow Venturi nozzle with a toroidal throat is investigated in the laminar boundary layer region. Din ranged from 5.00D to 1.73D, which were obtained by shaving the inlet of a high-precision nozzle that was originally complying with ISO 9300. Flat, freestanding lip, and frustum inlets were investigated.Copyright

Effect of Inlet Curvature on the Discharge Coefficients of Toroidal-Throat Critical-Flow Venturi Nozzles (Keynote)

The effect of the inlet curvature R on the discharge coefficients of toroidal throat critical flow Venturi nozzles is discussed based on calibration results of high-precision nozzles HPNs with R = 1.0, 1.2, 1.5, 1.8, 2.0, and 2.5D, where D is the throat diameter (9.6, 13.4, and 18.9 mm). The Reynolds numbers RD range from 1.2×105 to 1.2×106 , corresponding to absolute upstream pressures of 0.1 to 0.7 MPa. The calibrations were performed by a constant volume tank system developed for the primary standard in Japan.© 2005 ASME