http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이종훈(J. H. Lee),이연원(Y. W. Lee),김재환(J. H. Kim) 한국동력기계공학회 2005 한국동력기계공학회 학술대회 논문집 Vol.- No.-
In the technical development of automobiles, environmental effort is risen with air pollution problem. Hydrocarbon (HC), one of dangerous pollutants in automobiles, is generated about 20~35% in total amount by crankcase blowby gas. A PCV valve eliminates this gas using recirculation loop to control it automatically using return spring. The PCV valve is very small component in an automotive engine but it is very important. Although it has very simple operating principle such as the spool is moved by force balance between fluid force and elastic force, designing a PCV valve is difficult for interaction between fluid and solid. In this study, our purpose is to develop a design program for PCV valve and we verify its efficiency. We used both Euler's equation and 4th order Runge-Kutta method to predict spool displacements and flow areas. Comparing with real products, we found that both spool diameter and displacement were predicted well. But, in comparison with flow rate we could found its difference because of the assumption of non viscous flow, that is Euler's equation.
정호윤(H. Y. Jung),박재성(J. S. Park),권지혁(J. H. Kwon),이종훈(J. H. Lee),이연원(Y. W. Lee) 한국동력기계공학회 2006 한국동력기계공학회 학술대회 논문집 Vol.- No.-
Recently, we have many problems on the process of the sewage sludge. In past, the sewage sludge was treated by reclaimed land or thrown away in the sea. But these methods caused environmental pollution, Today, many researchers are studying various methods for reducing its volume. One of these method, this study is to reduce the moisture of sewage sludge and to solidify it using a dryer and curing equipment. In this research, we investigated about design parameter and operation condition of the equipment. The curing equipment reduces the percentage of water content from 30% of dryer to 10%. So, we have to study the curing characteristics and performance of curing equipment. For example, there are internal flow characteristics and change of the percentage of water content. And we investigated the change of data at outlet along the initial condition, temperature, humidity and air flow. Using this data, we achieve the experimental results of curing efficiency by each geometry and operating condition. And we also investigated numerical analysis of internal flow using CFD code. This research is basic study for optimal design of the curing equipment.
정호윤(H. Y. Jung),권지혁(J. H. Kwon),이종훈(J. H. Lee),최윤환(Y. H. Choi),이연원(Y. W. Lee) 한국동력기계공학회 2005 한국동력기계공학회 학술대회 논문집 Vol.- No.-
Now a days Automobiles are becoming more important in our life, the study on piston of engine is needed because, piston's cooling and lubrication of piston have an effect on the life and efficiency of engine directly. So, this study is about nozzle part of oil jet for cooling piston in the automotive engine. Piston exposes combustion gas of over 2000℃ and is shocked high pressure at the time of explosion shortly. Furthermore strong friction occurs by high speed rotation. The cooling system is considered from oil jet to piston. The previous system cooled the lower part of piston only. So, efficiency was low. To improve this system, make the oil gallery in the piston, and oil flows into the gallery. The value of oil flow rate into the gallery is important. Consequently, the point of this study is the research of investigation of flow characteristics for variable Re number. This study has been modelled by a commercial CFD code FLUENT, allowing to assess its validity.
이종훈(J.H. Lee),한병윤(B.Y. Han),곽수민(S.M. Kwak),이연원(Y.W. Lee),김찬욱(C.W. Kim) 한국전산유체공학회 2003 한국전산유체공학회 학술대회논문집 Vol.2003 No.-
In order to analyze the heat transfer phenomena in the plasma flames, a mathematical model describing heat and fluid flow in an electric arc has been developed and used to predict heat transfer from the arc to the steel bath in a DC Electric Arc Furnace. The arc model takes the separate contributions to the heat transfer from each involved mechanism into account, i.e. radiation, convection and energy transported by electrons. The finite volume method and a SIMPLE algorithm are used for solving the governing MHD equations, i.e., conservation equations of mass, momentum, and energy together with the equations describing a k-ε model for turbulence. The model predicts heat transfer for different currents and arc lengths. Finally these calculation results can be used as a useful insight into plasma phenomena of the industrial-scale electric arc furnace. From these results, it can be concluded that higher arc current and longer arc length give high heat transfer.
Moving Mesh를 이용한 PCV 밸브의 내부유동 수치해석
이종훈(J. H. Lee),이연원(Y. W. Lee),김재환(J. H. Kim) 한국동력기계공학회 2005 한국동력기계공학회 학술대회 논문집 Vol.- No.-
A great deal of exhaust gas inside a combustion room goes out through exhaust pipe but residual gas, is called "Blowby gas", enters the crankcase through a small gap between the piston and the cylinder wall. Here, if the crankcase isn't vented, this causes many bad effects such as lubricant oil contamination, corrosion by that and crankcase explosion by rising pressure. So, most automobiles are constituted with a PCV (Positive Crankcase Ventilation) system to prevent previous problems. PCV valve is the most important part in this ventilation system. When companies are manufacturing new engines, engineers are designing it depending on their experiments than theoretical knowledge. Much effort and many times are needed for new development. This study will show quantitative results to increase the possibilities of reduction of developing time.
Oil Jet의 볼 체크 밸브의 내부 유동에 대한 수치해석
권지혁(J. H. Kwon),정호윤(H. Y. Jung),이종훈(J. H. Lee),최윤환(Y. H. Choi),이연원(Y. W. Lee) 한국동력기계공학회 2005 한국동력기계공학회 학술대회 논문집 Vol.- No.-
As vehicles are recently becoming more important in our life, the study for engine capacity has been conducted for many years. Specially, the study on lubrication in the engine is needed to develop engine capacity. The role of lubrication is to reduce fraction, manage the temperature and protect from corrosion etc. At the view point of the engine, lubrication and cooling of the engine have an effect on the life and efficiency, so we have to study this problem. Ball check valve is located in the inlet of the Oil Jet. Ball check valve is used to control the flow rate of the engine oil, which cools and lubricates the engine. Flow rate at the oil jet is very important, so the study for this problem is needed to conduct researches. The point of this study is to compute the flow rate and the flow in oil jet. The results of this study is that the mass flow rate is satisfied with the research which is obtained at the experiment.