http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
균일 사 염색을 위한 최적 Spindle 형상 설계에 관한 연구
강민성(Min-Sung Kang),김재형(Jae-Hyung Kim),노석홍(Seok-Hong Noh),김용대(Young-Dae Kim),김희동(Heuy-Dong Kim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.10
In the field of yarn dyeing, the most generally employed method is a type of package dyeing which uses a package cheeses stacked on a spindle made of a perforated tube. Spindles up to now, have been designed without considering the characteristics of dyeing liquid, focusing only on the geometric configuration which cause many problems such as lack of level dyeing. To improve the level dyeing and find the appropriate spindle configuration for the most effective dyeing process, this study examines the spindle flow-field in detail, using a computational method. Flow characteristics inside the spindle have been investigated with varying in porosity, porous diameter and the velocity of the flow. The results show that the total pressure of the flow through the spindle is used to overcome body force. The characteristics of the flow from the porous spindle could also be observed. Based on the results from this study, an effective spindle configuration for level-dyeing has been proposed.
강민성(Min-Sung Kang),이호준(Ho-June Lee),노석홍(Seok-Hong Noh),전두환(Doo-Hwan Chun),김희동(Heuy-Dong Kim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5
In the field of yarn dyeing, the most generally employed method is a type of package dyeing which uses a package of cheeses stacked on a spindle made of a perforated tube. In order to understand the process of level dyeing, it is essential to perform a study of the porous flow through the spindle for the cheese dyeing method. In this paper, the axisymmetric, incompressible, Navier-Stokes equations are solved for several spindle configurations using a fully implicit finite volume scheme. For investigating the flow patterns through the spindle, porous diameter and porosity is varied in the present study. The computational results show that the total pressure loss depends only on the velocity of inflow regardless of porous diameter and porosity and a large percentage of the mass flow rate through the spindle is discharged at the upside of the spindle. Therefore, it is required to design a new spindle to obtain the level dyeing.
박시우(Si Woo Park),전두환(Du Hwan Chun),조경철(Kyung Chul Cho),노석홍(Seok Hong Noh),나혜중(Hae Joong Na) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11
Generally, jet loom is exposed to a more vibration and noise problems than those of the other textile machinery due to weaving mechanism. Thus jet loom weaving mechanism is important to understand the dynamic characteristics for reduction design of vibration and noise. In this study, the devised model is used to analyze the reaction force of a air jet loom using ADAMS. The simulation results are good agreement with the vibration and noise reduction design.
가중계수법을 이용한 5회선 초음파 유량계의 유속적분방법의 불확도 평가
이호준(Ho-June Lee),이권희(Kwon-Hee Lee),노석홍(Seok-Hong Noh),황상윤(Sang-Yoon Hwang),노영아(Young-Ah Noh) 한국유체기계학회 2005 유체기계 연구개발 발표회 논문집 Vol.- No.-
Flow rate measurement uncertainties of the ultrasonic flow meter are generally influenced by many different factors, such as Reynolds number, flow distortion, turbulence intensity, wall surface roughness, velocity integration method along the acoustic paths, and transducer installation method, etc. Of these influencing factors, one of the most important uncertainties comes from the velocity integration method. In the present study, a optimization weighting factor method for 5-chord, which is given by a function of the chord locations of acoustic paths, is employed to obtain the mean velocity in the flow through a pipe. The power law profile is assumed to model the axi-symmetric pipe flow and its results are compared with the present weighting factor concept. For an asymmetric pipe flow, the Salami flow model is applied to obtain the velocity profiles. These theoretical methods are also compared with the previous Gaussian, Chebyshev, and Tailor methods. The results obtained show that for the fully developed turbulent pipe flows with surface roughness effects, the present weighting factor method is much less sensitive than Chebyshev and Tailor methods, leading to a better reliability in flow rate measurement using the ultrasonic flow meters.
김도섭(Do-seop KIM),Qiang YU,조순옥(Soon-ok JO),노석홍(Seok-hong NOH),전두환(Du-hwan CHUN) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.5
There have been serious debates about whether Pb should be removed from solder joints, in view of environmental problems. Therefore, many studies have been aggressively undertaken to develop technologies for replacing Sn-Pb solder with lead-free alternative. From the results obtained so far, it has been proven that the fatigue strength in lead-free solder joints is almost equivalent to the fatigue strength of Sn-Pb eutectic solder joints. However, a new problem is that voids are very easily formed in lead-free solder joints during the reflow process, and the effect of the voids on the fatigue strength of solder joints has attracted attention. In this study, the relationship between the voids and fatigue strength of solder joints was examined using mechanical shear fatigue test and FEM (finite element method) analysis. Using the mechanical shear fatigue test, the effect of the position and size of voids on fatigue crack initiation and crack propagation has been investigated. And quantitive evaluation of fatigue life of solder joints with the voids has been enabled by Manson-Coffin's law and Miner' rule.
이호준(Ho-June Lee),이권희(Kwon-Heuy Lee),이창호(Chang-Ho Lee),장효준(Hyo-June Jang),노석홍(Seok-Hong Noh) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11
The inclined jet issued from a soft nozzle has been used to dye and transfer the fabric in dyeing machinery. The efficiency of these dyeing machines is dependent on the jet characteristics such as jet angle, flow rate, velocity, pressure distributions, etc. In this study, We carried out experiment and computational analysis to understand the dyeing jet characteristics in the rapid dyeing machinery. An axi-symmetric incompressible Navier-Stokes equation with k- turbulence model and implicit VOF method. are used in computation. The pressure ratio applied in nozzle operation is in the range of 1.5 and 2.5, the diameter of nozzle exit is in the range of 1.74 ㎜ ~ 3.71 ㎜. Computational results are compared with experimental results.