Falk Sebastian, Kniesburges Stefan, Schoder Stefan, Jakubaß Bernhard, Maurerlehner Paul, Echternach Matthias, Kaltenbacher Manfred, Döllinger Michael
Division of Phoniatrics and Pediatric Audiology, Department of Otorhinolaryngology, Head & Neck Surgery, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
Institute of Fundamentals and Theory in Electrical Engineering, Division Vibro- and Aeroacoustics, Graz University of Technology, Graz, Austria.
Front Physiol. 2021 Mar 8;12:616985. doi: 10.3389/fphys.2021.616985. eCollection 2021.
For the clinical analysis of underlying mechanisms of voice disorders, we developed a numerical aeroacoustic larynx model, called , that mimics commonly observed functional laryngeal disorders as glottal insufficiency and vibrational left-right asymmetries. The model is a combination of the Finite Volume (FV) CFD solver Star-CCM+ and the Finite Element (FE) aeroacoustic solver CFS++. models turbulence using Large Eddy Simulations (LES) and the acoustic wave propagation with the perturbed convective wave equation (PCWE). Its geometry corresponds to a simplified larynx and a vocal tract model representing the vowel /a/. The oscillations of the vocal folds are externally driven. In total, 10 configurations with different degrees of functional-based disorders were simulated and analyzed. The energy transfer between the glottal airflow and the vocal folds decreases with an increasing glottal insufficiency and potentially reflects the higher effort during speech for patients being concerned. This loss of energy transfer may also have an essential influence on the quality of the sound signal as expressed by decreasing sound pressure level (SPL), Cepstral Peak Prominence (CPP), and Vocal Efficiency (VE). Asymmetry in the vocal fold oscillations also reduces the quality of the sound signal. However, confirmed previous clinical and experimental observations that a high level of glottal insufficiency worsens the acoustic signal quality more than oscillatory left-right asymmetry. Both symptoms in combination will further reduce the quality of the sound signal. In summary, allows for detailed analysis of the origins of disordered voice production and hence fosters the further understanding of laryngeal physiology, including occurring dependencies. A current walltime of 10 h/cycle is, with a prospective increase in computing power, auspicious for a future clinical use of .
为了对嗓音障碍的潜在机制进行临床分析,我们开发了一种数值气动声学喉部模型,称为 ,它模拟了常见的功能性喉部障碍,如声门闭合不全和振动左右不对称。该模型是有限体积(FV)计算流体动力学(CFD)求解器Star-CCM+和有限元(FE)气动声学求解器CFS++的组合。 使用大涡模拟(LES)对湍流进行建模,并使用扰动对流波动方程(PCWE)对声波传播进行建模。其几何形状对应于一个简化的喉部和一个代表元音/a/的声道模型。声带的振动由外部驱动。总共模拟和分析了10种具有不同程度基于功能障碍的配置。随着声门闭合不全的增加,声门气流与声带之间的能量传递减少,这可能反映了相关患者在说话时需要付出更大的努力。这种能量传递的损失也可能对声音信号的质量产生重要影响,表现为声压级(SPL)、谐波峰值突出度(CPP)和嗓音效率(VE)的降低。声带振动的不对称也会降低声音信号的质量。然而, 证实了先前的临床和实验观察结果,即高水平的声门闭合不全比左右振动不对称更会恶化声学信号质量。两种症状同时出现会进一步降低声音信号的质量。总之, 允许对嗓音产生紊乱的起源进行详细分析,从而促进对喉部生理学的进一步理解,包括其中存在的相关性。目前每个周期10小时的运行时间,随着计算能力的预期提高,对于 的未来临床应用是有利的。