Decker Gifford Z, Thomson Scott L
Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602, USA.
J Voice. 2007 May;21(3):273-84. doi: 10.1016/j.jvoice.2005.12.002. Epub 2006 Feb 28.
The use of the mechanical energy (ME) equation for fluid flow, an extension of the Bernoulli equation, to predict the aerodynamic loading on a two-dimensional finite element vocal fold model is examined. Three steady, one-dimensional ME flow models, incorporating different methods of flow separation point prediction, were compared. For two models, determination of the flow separation point was based on fixed ratios of the glottal area at separation to the minimum glottal area; for the third model, the separation point determination was based on fluid mechanics boundary layer theory. Results of flow rate, separation point, and intraglottal pressure distribution were compared with those of an unsteady, two-dimensional, finite element Navier-Stokes model. Cases were considered with a rigid glottal profile as well as with a vibrating vocal fold. For small glottal widths, the three ME flow models yielded good predictions of flow rate and intraglottal pressure distribution, but poor predictions of separation location. For larger orifice widths, the ME models were poor predictors of flow rate and intraglottal pressure, but they satisfactorily predicted separation location. For the vibrating vocal fold case, all models resulted in similar predictions of mean intraglottal pressure, maximum orifice area, and vibration frequency, but vastly different predictions of separation location and maximum flow rate.
研究了将流体流动的机械能（ME）方程（伯努利方程的扩展）用于预测二维有限元声带模型上的气动载荷。比较了三种稳定的一维ME流动模型，它们采用了不同的流动分离点预测方法。对于其中两种模型，流动分离点的确定基于分离时声门面积与最小声门面积的固定比例；对于第三种模型，分离点的确定基于流体力学边界层理论。将流速、分离点和声门内压力分布的结果与非定常二维有限元纳维-斯托克斯模型的结果进行了比较。考虑了刚性声门轮廓以及振动声带的情况。对于较小的声门宽度，三种ME流动模型对流速和声门内压力分布的预测较好，但对分离位置的预测较差。对于较大的孔口宽度，ME模型对流速和声门内压力的预测较差，但它们对分离位置的预测令人满意。对于振动声带的情况，所有模型对声门内平均压力、最大孔口面积和振动频率的预测相似，但对分离位置和最大流速的预测差异很大。
