Summary
Objectives
The purpose of this work was twofold. First, we aimed to develop an exact analytical
model for tubes used in semi-occluded vocal tract exercises to gain a quantitative
insight into the relationship between flow resistance and the tube's geometric parameters.
The second goal was to provide an isometric resistance chart that can be used by clinicians
to indicate either the diameter or the length of a tube, so as to provide the same
flow resistance of a reference tube.
Methods
The theory for confined flows based on the Darcy-Weisbach equation was used to derive
the analytical model, in which the friction factor was obtained by an explicit approximation
with error smaller than 0.4%. The isometric resistance chart was generated with the
analytical model, assuming the volume flow to be constant and equal to 0.4 L/s.
Results
The results obtained from the model agreed very well with both experimental and theoretical
results from the literature, particularly for tubes longer than 6 cm and with inner
diameters greater than 4.1 mm. In general, the analytical model slightly underestimates
the back pressure for shorter and thinner tubes. For these cases, the maximum difference
between analytical and experimental results corresponds to ≈5%.
Conclusions
Analysis of the equation terms indicated that the flow resistance is significantly
more sensitive to variations in the inner diameter than to variations on the tube's
length, which agrees with experimental results found in the literature. Moreover,
the effect of the mouth configuration is negligible for tubes whose length are one
order of magnitude greater the the inner diameter. Nevertheless, for short tubes the
mouth configuration becomes a significant parameter and can be described by the ratio
between the tube's inner diameter and the effective diameter of the patient's oral
cavity. The analytical model presented in this work can be applied to the entire set
of tube geometries found in clinical practice and constitutes a straightforward tool
for designing tubes for semi-occluded vocal tract exercises with specific therapeutic
purposes or patient needs.
Key Words
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Journal of VoiceAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Voice training and therapy with a semi-occluded vocal tract: rationale and scientific underpinnings.J Speech Lang Hear Res. 2006; 49: 448-459
- Vocal tract and glottal function during and after vocal exercises with resonance tube and straw.J Voice. 2013; 27: 523-534
- Semioccluded vocal tract exercises: changes in laryngeal and pharyngeal activity during stroboscopy.J Voice. 2016; 30: 377-379
- Resonance tube phonation in water—the effect of tube diameter and water depth on back pressure and bubble characteristics at different airflows.J Voice. 2018; 32: 126.e11-126.e22
- Effects of straw phonation through tubes of varied lengths on sustained vowels in normal-voiced participants.J Voice. 2017; (in press)https://doi.org/10.1016/j.jvoice.2017.05.015
- A quantitative output-cost ratio in voice production.J Speech Lang Hearing Res. 2001; 44: 29-37
- The resonance tube method in voice therapy: description and practical implementations.Logoped Phoniatr Vocol. 2007; 32: 165-170
- Immediate effects of the Finnish resonance tube method on behavioral dysphonia.J Voice. 2013; 27: 717-722
- Short-term effect of two semi-occluded vocal tract training programs on the vocal quality of future occupational voice users: resonant voice training using nasal consonants versus straw phonation.J Speech Lang Hear Res. 2017; 60: 2519-2536
- Controlled and randomized trial of intensive short-term voice therapy with finger kazoo in teachers.Audiol Commun Res. 2017; 22: e.1791
- Comparison of effects of finger kazoo and tube phonation techniques in women with normal voice.Audiol Commun Res. 2016; 21: e.1554
- Semioccluded vocal tract exercises: literature review.Revista CEFAC. 2013; 15: 1679-1689
- Investigation of the immediate effects of two semi-occluded vocal tract exercises.Pró-Fono R Atual Cient. 2008; : 261-266
- Effects on vocal fold collision and phonation threshold pressure of resonance tube phonation with tube end in water.J Speech Lang Hear Res. 2013; 56: 1530-1538
- Phonation into a glass tube immersed in water: vocal perceptive auditory analysis and videolaryngoscopy in women without laryngeal disorders, complaints or vocal alterations.Revista CEFAC. 2015; : 1760-1772
- Immediate effects of phonation into a straw exercise.Braz J Otorhinolaryngol. 2011; 77: 461-465
- Resonance tube or lax vox?.J Voice. 2017; 31 (in press): 430-437
- Characterization of flow-resistant tubes used for semi-occluded vocal tract training and therapy.J Voice. 2017; 31: 113-121
- The flow and pressure relationships in different tubes commonly used for semi-occluded vocal tract exercises.J Voice. 2016; 30: 36-41
- Air pressure and contact quotient measures during different semioccluded postures in subjects with different voice conditions.J Voice. 2016; 30: 759-769
- Vertical laryngeal position and oral pressure variations during resonance tube phonation in water and in air. A pilot study.Logoped Phoniatr Vocol. 2014; 41: 117-123
- An introduction to fluid dynamics.(Cambridge University Press)1967
- Fluid Mechanics.3rd ed. Elsevier Academic Press, Amsterdam, Boston, MA2004
- Experiments with fluid friction in roughened pipes.Proc R Soc Lond A Math Phys Sci. 1937; 161: 367-381
- Simple and explicit formulas for the friction factor in turbulent flow.J Fluids Eng. 1983; 105: 89-90
- Explicit equations for pipe-flow problems.J Hydraul Div. 1976; 102: 657-664
- Comparison of the iterative approximations of the Colebrook-White equation.Hydrocarbon Process. 2008; 87: 79-83
- Flow of fluids through valves, fittings, and pipe.(Technical paper, Crane Co)1988
- Engineering data book—gas processing.(12th Edition, Vol. I and II of Technical paper, Gas Processors Suppliers Association)2004
- Round gas jets submerged in water.Int J Multiph Flow. 2013; 48: 46-57
- Formation and development of submerged air jets.J Mech Eng. 2014; 44: 137-141
- A model for bubble-to-jet transition at a submerged orifice.Chem Eng Sci. 1999; 54: 4053-4060
Article info
Publication history
Published online: May 31, 2018
Accepted:
March 23,
2018
Identification
Copyright
© 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
