Petculescu A, Wilen L A
Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701, USA.
J Acoust Soc Am. 2003 Mar;113(3):1282-92. doi: 10.1121/1.1543932.
A nonresonant, lumped-element technique is used to investigate the behavior of tapered cylindrical flow constrictions (jet pumps) in the nonlinear oscillatory flow regime. The array of samples studied spans a wide range of inlet curvature radii and taper angles. By measuring the rectified steady pressure component developed across a jet pump as well as the acoustic impedance, the minor loss coefficients for flow into and out of the narrow end of the jet pump are determined. These coefficients are found to be relatively insensitive to all but the smallest curvature radii (i.e., sharp edges). For fixed radius of curvature, the inflow minor loss coefficient increases with increasing taper angle while the outflow coefficient remains relatively constant. For all of the samples, the steady flow minor loss coefficients are also measured and compared to their oscillatory flow counterparts. The agreement is good, confirming the so-called Iguchi hypothesis.
采用一种非共振集总元件技术来研究非线性振荡流态下锥形圆柱流收缩装置（喷射泵）的性能。所研究的样本阵列涵盖了广泛的入口曲率半径和锥角范围。通过测量喷射泵两端产生的整流稳态压力分量以及声阻抗，确定了流入和流出喷射泵窄端的局部损失系数。发现这些系数除了对最小曲率半径（即尖锐边缘）外，对其他因素相对不敏感。对于固定的曲率半径，流入局部损失系数随锥角增大而增加，而流出系数则保持相对恒定。对于所有样本，还测量了稳态流局部损失系数，并与振荡流对应的系数进行了比较。两者吻合良好，证实了所谓的井口假说。
