• 대한기계학회논문집B
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• 제26권6호
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• pp.811-816
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• 2002

For the first time, airflow in the nasal cavity of a normal Korean adult is investigated experimentally by PIV measurement. Nasal airflow can be subdivided into two interrelated categories; nasal airflow resistance and heat and mass transfer between the air stream and the walls of the nasal cavity. In this study, thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone. a transparent rectangular box containing the complex nasal cavity can be made fur PIV experiments. The CBC PIV algorithm is used for analysis. Average and RMS distributions are obtained for inspirational and expiration nasal airflows. Data fer the airflow at the end of meatuses are obtained for the first time. Comparisons between western and Korean nasal airflows are appreciated. Due to the difference in geometry of the frontal part of nasal cavity, the flow near nares shows the difference.

• 대한기계학회논문집B
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• 제29권1호
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• pp.103-109
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• 2005

Airflow in the nasal cavity of a normal Korean adult is investigated experimentally by tomographic PIV measurement. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiology and pathology aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. All of these researches on nasal airflow are under the condition of constant flow-rate. In this study, nasal cavity flow with the physiological period is investigated by tomographic PIV, for the first time. A pumping system that can produce the periodic flow is created. Thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone, a transparent rectangular box containing the complex nasal cavity can be made for PIV, The CBC PIV algorithm is used for analysis. Phase-averaged mean and RMS velocity distributions are obtained for inspirational and expiration nasal airflows. The comparison with the constant flow case is appreciated. There exist many flow patterns depending on each phase.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1479-1483
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• 2008

The three main physiological functions of nose are air-conditioning, filtering and smelling. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time, airflow inside normal nasal cavity is investigated numerically by the FVM general purpose code. The comparisons with PIV measurement are appreciated. Heat and humidity transfer is dealt numerically. Dense CT data and careful treatment of model surface under the ENT doctor’s advice provide more sophisticated cavity models for both PIV experiment and numerical grid system. Average and RMS velocity distributions have been obtained for inspirational and expirational nasal. Temperature distribution, heat and humidity transfer through the mucosa are obtained.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.498-501
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• 2008

Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal, abnormal, and deformed nasal cavity models cavity models by PIV under both constant and periodic flow conditions. In this time normal and several deformed nasal cavity models, which simulate surgical operation, Turbinectomy, are investigated numerically by the FVM general purpose code and PIV analysis. The comparisons of these results are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticated cavity models. The Davis (LaVision Co.) code is used for PIV flow analysis. Average and RMS distributions have been obtained for inspirational and expirational nasal airflows in the normal and deformed nasal cavities.

• Journal of Mechanical Science and Technology
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• 제18권10호
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• pp.1799-1808
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• 2004

Knowledge of airflow characteristics in nasal cavity is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. Since the final goal of these works is their contribution to the diagnosisand treatment of nasal diseases, the next step on this topic is naturally studies for disordered nasal cavities. In this paper, as the first application, airflows in the normal and abnormal nasal cavities with adenoid vegetation are investigated experimentally by PIV, and comparisons of both cases are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticatedcavity model. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Airflow characteristics that are related with the abnormalities in nasal cavity are presented.

• 대한기계학회논문집B
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• 제33권6호
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• pp.461-467
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• 2009

Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal, abnormal, and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time normal and several deformed nasal cavity models, which simulate surgical operation, Turbinectomy, are investigated numerically by the FVM general purpose code and PIV analysis. The comparisons of these results are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticated cavity models. The Davis (LaVision Co.) code is used for PIV flow analysis. Average and RMS distributions have been obtained for inspirational and expirational nasal airflows in the normal and deformed nasal cavities.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2001년도 Proceedings of 2001 Korea-Japan Joint Seminar on Particle Image Velocimetry
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• pp.138-150
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• 2001

Researchers have investigated nasal flow both numerically and experimentally for centuries. Experimental studies most have suffered from various limitations necessary to allow the measurements to be obtained with available equipment. Nasal airflow can be subdivided into two interrelated categories; nasal airflow resistance and heat and mass transfer between the air stream and the walls of the nasal cavity. In this study, thanks to a new method for model casting by a combination of Rapid prototyping and curing of clear silicone, a transparent rectangular box containing the complex nasal cavity is made for PIV experiments. The CBC PIV algorithm is used for analysis. Average and RMS distributions are obtained for inspirational and expiration nasal airflows. Comparison between western and Korean nasal air flows are appreciated. Flow fields for Korean model shows some differences from western's. Flow resistances for breathing are measured with varying flow rates.

• 대한치과교정학회지
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• 제22권1호
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• pp.31-42
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• 1992

This study was designed to analyze normal nasal respiratory resistance in prepubertal children. The subjects consisted of 30 prepubertal children (male: 15, female: 15). The mean age was 11.4 years in male children and 11.5 years in female children. The results were as follows: I. The normal nasal respiratory patency was lower than the normal values from RION corp. 2. The normal nasal respiratory airflow rates showed no sexual differences. And there were no differences between inspiration and expiration. 3. Before and after use of nasal decongestants, there were no significant differences of normal nasal respiratory airflow rates and after the administration of nasal decongestants, nasal respiratory patency manifested lower variability. 4. The normal nasal respiratory resistance without nasal decongestants at 150 Pascal in inspiration was $0.30Pa/cm^3/sec({\pm}0.07)$ and peak nasal inspiratory airflow rate was $1016.83cm^3/sec({\pm}223.89)$. 5. The normal nasal respiratory resistance with nasal decongestant at 150 Pascal in inspiration was $0.25Pa/cm^3/sec({\pm}0.05)$ and peak nasal inspiratory airflow rate was $1148.33cm^3/sec({\pm}234.29)$.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.566-569
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• 2001

Researchers have invectigated nasal flow both numerically and experimentally for centuries. Experimental studies most have suffered from various limitations necessary to allow the measurements to be obtained with available equipment. Nasal airflow can be subdivided into two interrelated categories; nasal airflow resistance and heat and mass transfer between the air stream and the walls of the nasal cavity. In this study, thanks to a new method for model casting by a combination of Rapid prototyping and Solidification of clear silicone, a transparent rectangular box containing the complex nasal cavity is made for PIV experiments. The CBC PIV algorithm is used for analysis.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1687-1692
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• 2004

CT 사진을 이용하여 살아있는 사람의 비강 형상을 얻고 RP 를 이용하여 모형을 만들고 이 모형 으로 정교한 비강 유로 모형을 제작하였고, 호흡을 정확하게 모사하는 펌프를 만들었다. 사람의 호흡 데이터를 이용하여 캠을 제작하고 대형 피스 톤 펌프를 만들어 사람의 호흡을 정확 하게 모사 하였다. 이를 이용하여 생리적 주기를 갖는 비강 내 유동에 대한 결과를 획득하고 기존의 일정유량 하의 실험결과와 비교 분석하였다.