Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl最新文献_第6页

Analysis of Pressure Field on Wire-Wrapped Pin Bundle Surface for Concerns of FSI 考虑FSI的绕线销束表面压力场分析

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83521

L. Brockmeyer, A. Obabko, E. Merzari, Y. Hassan

{"title":"Analysis of Pressure Field on Wire-Wrapped Pin Bundle Surface for Concerns of FSI","authors":"L. Brockmeyer, A. Obabko, E. Merzari, Y. Hassan","doi":"10.1115/FEDSM2018-83521","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83521","url":null,"abstract":"Wire wrapped fuel pins, typical of sodium fast reactor designs, introduce a strong secondary rotational flow and enhanced mixing compared to bare pins found in many other nuclear reactor designs. The transverse flow is created by deflection off of the helical wires, exerting a force onto the wires. The resulting pressure field can be more intricate than found for bare fuel pins. There is an increased concern for fluid structure interactions such as twisting, bending, and vibration due to the fluid deflection and increased transverse flow. The present study uses LES to simulate the fluid flow in a wire-wrapped fuel pin bundle. The simulation is performed using Nek5000, a spectral element LES/DNS code. The time-dependent, fluctuating pressure field at the surface of select fuel pins are specifically captured for analysis. Statistical analysis is performed on the pressure data to find areas of persistent force or bending moment, which over large periods of time may result in deformation of the pins. Further, the pressure data is analyzed in search of areas with large fluctuations in pressure, which may result in flow induced vibrations. Frequency spectra of the force fluctuations are analyzed.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79700547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Experimental Observation of Bubbles Released in Horizontal Water Flow 水平水流中气泡释放的实验观察

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83185

C. Kang, Yanguang Ji, Lili Zhang, Wei Zhang

{"title":"Experimental Observation of Bubbles Released in Horizontal Water Flow","authors":"C. Kang, Yanguang Ji, Lili Zhang, Wei Zhang","doi":"10.1115/FEDSM2018-83185","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83185","url":null,"abstract":"To investigate the characteristics of the bubble which is exposed to the liquid cross flow, the method of ventilation was adopted and air was injected into the water flow. A water tunnel was used to provide uniform water flow with variable velocity magnitude. A high speed camera was used to record instantaneous bubble images. An image-processing code was developed to identify bubble profile and to calculate bubble parameters. The effects of water flow velocity and the flow rate of the injected air were considered. The results indicate that bubble size decreases as the water velocity increases; meanwhile, ellipsoidal bubble shape is transformed into rounded shape. The variation in the air flow rate leads to a slight change of bubble size as well the bubble shape. The bubble velocity fluctuates with the movement of the bubble, and the fluctuations are intensified as the water velocity decreases. As the balance between the forces exerted on the bubble is reached, an approximately linear relationship between the bubble velocity and the water flow velocity is proven. For a given bubble equivalent diameter, the bubble terminal velocity with the liquid cross flow is higher than that associated with stagnant water. For small Eötvös number, the consistency of the bubble aspect ratio in the cross flow and the stagnant water is manifested; however, large Eötvös number obtained here is beyond the range associated with the stagnant water, and the existing relationship is extended.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90337530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation on Loading-Induced Fluid Flow in Osteogenesis Imperfecta Bone 成骨不完全性骨负荷诱导的流体流动研究

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83496

N. V. Shrivas, A. Tiwari, Rakesh Kumar, D. Tripathi, Vasu Raman Sharma

{"title":"Investigation on Loading-Induced Fluid Flow in Osteogenesis Imperfecta Bone","authors":"N. V. Shrivas, A. Tiwari, Rakesh Kumar, D. Tripathi, Vasu Raman Sharma","doi":"10.1115/FEDSM2018-83496","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83496","url":null,"abstract":"Osteogenesis Imperfecta (OI) is a genetic bone disorder which is typically characterized by brittle bones with frequent fractures. It is also known as brittle bone disease. Surgical procedure is one of the ways adopted by clinicians for the management of OI. In recent years, it has however become clear that physical activity is equally important for managing OI in both children and adults. Exogenous mechanical stimulation e.g. prophylactic exercises may be useful in improving the bone mass and strength of OI bones as loading-induced mechanical components e.g. normal strain and canalicular fluid flow stimulate remodeling activities. Several studies have characterized the strain environment in OI bones, whereas, very few studies attempted to characterize the canalicular fluid flow. In the present study, we anticipate that canalicular fluid flow reduces in OI bone as compared to healthy bone under physiological loading. This work accordingly computes the canalicular fluid distribution in the single osteon model of OI and control/normal bones subjected to normal physiological loadings. A transversely isotropic poroelastic model of osteon is developed. Loading is applied in accordance with gait cycles reported for OI and healthy bones. Fluid distribution patterns computed for OI and healthy bones are compared at different time-points of stance phase of the gait cycle. A significant reduction in fluid flow is observed in case of OI bone as compared to healthy bone. This clearly indicates that improvements in physical activities or exercises can be designed to enhance the level of canalicular fluid flow to initiate possible osteogenic activities and the bone.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86038415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

An Experimental Study of Surface-Mounted Bluff Bodies Immersed in Deep Turbulent Boundary Layers 深湍流边界层中表面附着钝体的实验研究

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83498

Helen Amorin, Xingjun Fang, M. Tachie

{"title":"An Experimental Study of Surface-Mounted Bluff Bodies Immersed in Deep Turbulent Boundary Layers","authors":"Helen Amorin, Xingjun Fang, M. Tachie","doi":"10.1115/FEDSM2018-83498","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83498","url":null,"abstract":"This paper reports an experimental study conducted to investigate the effects of aspect ratio on the reattachment length and statistical properties in turbulent flow over three-dimensional surface-mounted bluff bodies. This study focuses on a surface-mounted body whose height is significantly smaller than the thickness of the approaching turbulent boundary layer. The studied aspect ratios of the step range from w/h = 0.5 to 20, where w and h denote the spanwise width and height of the step, respectively. All experiments were carried out in an open water channel, and the velocity measurements were performed using a time-resolved particle image velocimetry (TR-PIV) system. The Reynolds number, based on the freestream of the approach boundary layer and step height, is 12540, while the ratio of the boundary layer to step height is 4.83. Two distinct regions of separation are observed on top of the step and downstream of the step. In both separation regions, the reattachment length increases monotonically as aspect ratio increases from w/h = 0.5 to 8, and the reattachment length reaches an asymptotic value and does not vary significantly with aspect ratio larger than 8. The effects of aspect ratios on the mean velocities and Reynolds stresses were also examined.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84634840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of RANS, LES, and Hybrid RANS/LES Models for the Prediction of Low-Pr Turbulent Flows RANS、LES和混合RANS/LES模型对低pr湍流预测的评估

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83307

S. Bhushan, O. Elfajri, W. Jock, D. K. Walters, J. Lai, Y. Hassan, R. Jackson, A. Obabko, E. Merzari

引用次数: 2

Influence of Numerical Dissipation on Draft Tube Flows 数值耗散对尾水管流动的影响

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83225

Yao Jiang, Liu Yang, S. Nadarajah

引用次数: 0

Multi-Plane Characterization of the Turbulent Boundary Layer 湍流边界层的多平面特性

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83507

K. Dennis, K. Siddiqui

{"title":"Multi-Plane Characterization of the Turbulent Boundary Layer","authors":"K. Dennis, K. Siddiqui","doi":"10.1115/FEDSM2018-83507","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83507","url":null,"abstract":"The boundary layers are known for their significance in several engineering systems. In particular, the inner region of the turbulent boundary layer has been shown to play a significant role in controlling the dynamics of turbulent structures that are responsible for the transport of mass, heat and momentum. While substantial work has been done in the past to characterize the structure of turbulent flow in this region, the characterization of the three-dimensional turbulent flow structure is limited. This study reports a multi-plane particle image velocimetry (PIV) approach to investigate three-dimensional dynamics of the turbulent boundary layer in the near-wall region. Planar PIV is used to capture two-dimensional fluid velocity fields in several planes with respect to the fluid flow direction. These results are used to describe three-dimensional turbulent events given by key quantities such as mean and turbulent velocities and turbulent kinetic energy.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"1990 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88191586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Fluid Properties on Slug Dissipation in Enlarged Impacting Tee 膨胀冲击三通中流体特性对段塞消散的影响

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83313

Mobina Mohammadikharkeshi, Ramin Dabirian, O. Shoham, R. Mohan

{"title":"Effect of Fluid Properties on Slug Dissipation in Enlarged Impacting Tee","authors":"Mobina Mohammadikharkeshi, Ramin Dabirian, O. Shoham, R. Mohan","doi":"10.1115/FEDSM2018-83313","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83313","url":null,"abstract":"An experimental and theoretical investigation is conducted on the effect of inlet slug length and fluid properties on slug dissipation in an enlarged impacting tee-junction (EIT). The EIT is the building block of a multiphase manifold. Prediction of the slug dissipation length in the EIT provides a guideline for the optimum diameter and length of a manifold. A multiphase flow loop is utilized to investigate slug dissipation in an EIT. The EIT inlet pipe is inclined slightly upward at 5 degrees, in which stationary slugs of different lengths are formed. The generated slugs are pushed into the EIT branches by a pre-determined gas flow rate. Over 80 experimental runs are conducted with superficial gas velocities between 3 to 9 m/s and inlet slug lengths between 40d to 90d, for both air-water and air-oil flows. The experimental data confirm that increasing the superficial gas velocity, as well as the slug body length in the inlet pipe lead to increasing the slug dissipation length in the EIT branches. Furthermore, the data demonstrate that higher slug dissipation length is obtained with water as compared to oil. A mechanistic model is developed for the prediction of slug dissipation in an EIT. A comparison between the developed mechanistic model predictions and the experimental data show a discrepancy less than 20%.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86440790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Effects of an Underbody Device on the Characteristics of a Trailer Truck Wake Region 车底装置对拖车尾流区特性的影响

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83176

M. Ibrahim, M. Agelin-Chaab

{"title":"Effects of an Underbody Device on the Characteristics of a Trailer Truck Wake Region","authors":"M. Ibrahim, M. Agelin-Chaab","doi":"10.1115/FEDSM2018-83176","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83176","url":null,"abstract":"The aerodynamics of bluff bodies and flow separation are encountered in many industrial applications. Flow separation causes significant pressure fluctuations that can yield undesirable effects such as vibration, noise, and drag. It is well-known that at highway speeds, over 50% of the fuel is used by a road vehicle to overcome aerodynamic drag. Due to these reasons, bluff body aerodynamics has been the subject of intensive research interests for many decades. In this paper, a new concept of an underbody aerodynamic device is used to modify the turbulent wake region of a bluff body.\u0000 In particular, the underbody device was designed in order to allow for the recirculating flow to reattach and exit the underside of the bluff body while increasing the average speed of the flow and preventing side winds from disturbing the flow. This significantly reduces the underbody recirculation zone, which is a major source of drag. In addition, this ensures that the flow exits with minimum turbulence to reduce the size of the bluff body’s wake. The studies were conducted using the RANS based turbulence model, k-ω SST in ANSYS Fluent. A width-based Reynolds number of 1.1 × 106 was used to conduct the simulations in order to validate the baseline model with NASA’s wind tunnel data; which include the surface pressure coefficients and a drag coefficient. The paper focuses on the changes in the model’s wake that were introduced due to the device and their influence on the underside flow. The results showed that the device significantly reduced the recirculation at the underside of the bluff body. This was found to increase the coefficient of pressure at the base of the model, which reduced the size of the wake. These changes in the flow field resulted in an overall drag coefficient reduction of 4.1%.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81420884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Computational Analysis on Aerodynamics and Vortex Formation of Sleep Apnea 睡眠呼吸暂停空气动力学与涡旋形成的计算分析

Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl Pub Date : 2018-07-15 DOI: 10.1115/FEDSM2018-83257

Junshi Wang, Pan Han, Yaselly Sanchez, J. Xi, Haibo Dong

{"title":"Computational Analysis on Aerodynamics and Vortex Formation of Sleep Apnea","authors":"Junshi Wang, Pan Han, Yaselly Sanchez, J. Xi, Haibo Dong","doi":"10.1115/FEDSM2018-83257","DOIUrl":"https://doi.org/10.1115/FEDSM2018-83257","url":null,"abstract":"The fluid dynamics of air flow in the pharynx is critical to the vibration of the uvula and to the generation of the snoring sound. In this work, a combined experimental and computational approach was conducted to study the aerodynamics of the flow field in the human airway. An anatomically accurate pharynx model associated with different uvula kinematics was reconstructed from human magnetic resonance images (MRI) and high-speed photography. An immersed-boundary-method (IBM)-based direct numerical simulation (DNS) flow solver was used to simulate the corresponding unsteady flows in all their complexity. Analysis has been performed on vortex dynamics and pressure oscillation at various points of interest. Computations with varying airway obstructions, uvula kinematics, and vibrating frequencies were conducted to study the effect of the three factors on the vortex formation and pressure oscillation, respectively. It is found that the vortex formation is significantly affected by the airway width. The fast Fourier transformation (FFT) analysis of the pressure time history revealed the existence of higher order harmonics of the base frequency at significant amplitudes. It was also found that the pressure tended to oscillate more violently at higher uvula vibrating frequencies. Results from this work are expected to bring novel understanding on the sound producing in patients with sleep apnea and provide guidance for surgical interventions.","PeriodicalId":23480,"journal":{"name":"Volume 1: Flow Manipulation and Active Control; Bio-Inspired Fluid Mechanics; Boundary Layer and High-Speed Flows; Fluids Engineering Education; Transport Phenomena in Energy Conversion and Mixing; Turbulent Flows; Vortex Dynamics; DNS/LES and Hybrid RANS/LES Methods; Fluid Structure Interaction; Fl","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78312545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0