Wang Fig. 1 Human upper respiratory tract model 2 Nithiarasu Menter Menter's SST 3 Langtry-Menter Menter Langtry PIV 5 CFD SST

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听仁柴
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1 Vol. 31 No. 1 Chinese Journal of Biomedical Engineering February 2012 * L / min mm Pa m / s R A Numerical Simulation on Characteristics of Airflow Movement in Human Upper Respiratory Tract under Fluid-Solid Coupling SUN Dong LI Fu-Sheng XU Xin-Xi * ZHAO Xiu-Guo TAN Shu-Lin Institute of Medical EquipmentAcademy of Military Medicine SciencesNational Biological Protection Engineering Center Tianjin China AbstractResearch the effect of fluid-solid coupling on human upper respiratory tract can lead to deep understanding of the characteristics of the airflow in human upper respiratory tract and plays a very important role in analyzing the diffusiontransition and deposition patterns of aerosol in human upper respiratory tract. The numerical simulation of fluid-solid interaction mechanics was applied to simulate airflow movement in human upper respiratory tract model in the conditions of low intensive respiratory patterns respiratory flow is 30 L / minthe shape variation and shear stress distribution in human upper respiratory tract was discussedand the airflow movement in human upper respiratory tract was analyzed. Results showed that in the low intensive respiratory patternshuman upper respiratory tract moves backwardthe maximum displacement of the tertiary bronchus was mmthe anterior wall was stretchedand the posterior wall was compressed. The wall shearing stress in the mouth-throat model was larger than that in the trachea-triple bifurcationand the maximum shearing stress was Pa. The maximum of airflow velocity reached maximum at m / s in the glottis. The phenomenon of airflow separation appeared near the outer wall of the pharynx and the tracheaand the high velocity zone was created near the inner wall of the trachea. The airflow split at the divider and high velocity zone was generated near the inner wall of the trachea. Key wordsfluid-solid couplingupper respiratory tractwall shearing stressairflow movementnumerical simulation doi / j. issn * xuxxl@ sohu. com

2 Wang Fig. 1 Human upper respiratory tract model 2 Nithiarasu Menter Menter's SST 3 Langtry-Menter Menter Langtry PIV 5 CFD SST γ ργ + ρu iγ = t x i μ + μ t γ x i [ ( σ ) x ] + P γ - E γ σ γ = 1 1 γ i P γ E γ P γ = 2ρSF length F 0. onsetγ γ 2 E γ = 0. 06ρΩF turb γ50γ F turb = e - R T /4 R T = ρk / ωμ 4 Re v F onset1 = Re Re v = Reρy 2 S / μ 5 θc 1 = minmaxf onset Re v Langtry- 1 P Re γ γ θc F onset2 F 4 onset [ ] 1. 1 F onset3 = max 1 - R T F onset = maxf onset2 - F onset ρ t u i μ G0 ~ G3 μ t S Ω ARLA Aerosol Research Laboratory of y F Alberta 6 Stapleton K W 7 length 3 Re Weibel 8 θc R T Re v F turb E γ F onset P γ

3 1 91 Re 珟 θt σ s ρ s a s ρ Re 珟 θt + ρu 珟 jre θt = t x j d s = d f σ s n s = σ f n f u s = u f 15 P θt + σ x θt μ + μ t Re 珟 θt j [ ( x ) ] σ θt = 2 d n s f j P θt - P θt = ρ t Re θt - Re 珟 θt F θt t = 500μ - ρu 2 10 U F θt min max F wake e - y 4 ( δ ) / 50 ) 1. 0 ) 11 Re 珟 θt μ θ BL = δ BL = 15 ρu 2 θ BL δ = 50Ωy U δ BL 12 F wake = e - Re 2 ( ω 105 ) Re ω = ρωy2 13 μ F θt = ( ( γ - 1 /50 ( ) θ BL δ 30 L / imn F θt P θt Re 珘 θt F wake F θt particle image velocimetry PIV 30 L / min 11 9 MPa σ s = ρ s a s 14 2 a PIV 2 a b Fig. 2 Comparison of airflow patterns between experimental results and large eddy simulation results of the larynx. aexperimental results blarge eddy simulation results

4 b d x d y d z d = d x + d y + d z 3b 3 c 3d m / s m / 3a 30 L / min 10% c 3 d 3 3 a 3b L / min a b c d Fig. 3 The deformation of human upper respiratory tract model with breathing intensity Q = 30 L / min. acomparison of pre- and post- deformation b Longitudinal displacement c and d Lateral displacement

5 a b a b c d 4 c d Pa 4 30 L / min Von Mises stress a b c d Fig. 4 The Von Mises stress distribution of human upper respiratory tract model with breathing intensity Q = 30 L / min. afront view of anterior wall in human mouth-throat model bfront view of posterior wall in human mouth-throat model cfront view of anterior wall in trachea to triple bifurcation region dfront view of posterior wall in trachea to triple bifurcation region

6 c C-C' c D-D'E-E' 5 30 L / min 5a 5b 5c F-F' 5c H-H ' G2 G L / min a b c Fig. 5 Axial velocity contours at different cross section in human upper respiratory tract model with breathing intensity Q = 30 L / min. athe vertical section of human mouth-throat model bthe vertical section of trachea to triple bifurcation region cthe cross sections L / min

7 1 95 J. Acta Mecheanica Sinica Grgic B Finlay WH Heenan AF. Regional aerosol deposition and flow measurements in an idealized mouth and throatj. Aerosol Science Stapleton KWGuentsch EHoskinson MKet al. On the J suitability of k-εturbulence modeling for aerosol deposition in the 2 Wang YingLiu YingxiSun Xiuzhenet al. Numerical mouth and throata comparison with experimentj. Aerosol analysis of respiratory flow patterns within human upper airway Science Weibel ER. Morphometry of the human lungm. New York 3 Nithiarasu PLiu CBMassarotti N. Laminar and turbulent flow Academic Press calculations through a model human upper airways using 9 Menter FRLangtry RBLikki SRet al. A correlation based unstructured meshesj. Communications in Numerical Methods Engineering transition model using local variables Part 1-Model Formulation R. ASME 2004-GT Langtry RBMenter FRLikki SRet al. A correlation based PIV J transition model using local variables Part 2-Test Cases and Industrial ApplicationsR. ASME 2004-GT Wlofgang AWTimon R. Fluid-structure interaction in lower J airways of CT-based lung geometriesj. International Journal for Numerical Methods in Fluids

Fig. 1 1 The sketch for forced lead shear damper mm 45 mm 4 mm 200 mm 25 mm 2 mm mm Table 2 The energy dissip

Fig. 1 1 The sketch for forced lead shear damper mm 45 mm 4 mm 200 mm 25 mm 2 mm mm Table 2 The energy dissip * - 1 1 2 3 1. 100124 2. 100124 3. 210018 - ABAQUS - DOI 10. 13204 /j. gyjz201511033 EXPERIMENTAL STUDY AND THEORETICAL MODEL OF A NEW TYPE OF STEEL-LEAD DAMPING Shen Fei 1 Xue Suduo 1 Peng Lingyun 2 Ye