http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
송봉하(Bong-Ha Song),최윤호(Yun-Ho Choi) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
??The computations of chemically reacting turbulent flows are performed using the preconditioned Navier-Stokes solver coupled with turbulent transport and multi-species equations. The flowfields encountered in the vast majority of combustion applications take place at low speeds. Choi and Merkle’s preconditioning technique is used to overcome the convergence difficulties occurred at these low speed flows. The low-Reynolds number k?ε turbulence model proposed by Chien is used for turbulent flow predictions. Two numerical schemes, the implicit upwind ADI and DDLGS algorithms are used and are validated through the comparisons of computational and experimental results for H2/O2 reacting turbulent shear flow. Preconditioning formulation based on the ADI algorithm shows better convergence characteristics than that of other numerical techniques considered, such as preconditioned system using DDLGS algorithm and nonpreconditioned system using ADI or DDLGS algorithm.
상세화학반응 메커니즘을 이용한 HCCI엔진의 성능 해석기법 연구
송봉하(Bong-Ha Song),김동광(Dong-Kwang Kim),조남효(Nam-Hyo Cho) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
A numerical procedure was developed to predict main characteristics of an HCCI engine performance. The procedure is to couple a commercial code, Ricardo's WAVE, for one-dimensional engine performance analysis with a SENKIN routine using CHEMKIN libraries. When all the valves are closed the SENKIN routine is called to calculate in-cylinder combustion accurately using detailed chemical reaction mechanisms, while the WAVE code is to solve thermodynamics of all engine system except the combustion chamber. The WAVE-SENKIN code demonstrated its accuracy on the prediction of ignition time for a large natural gas fueled HCCI single cylinder engine. Pressure gradient just after ignition was predicted too high when compared with engine test data, and this could be mainly due to the assumption of single combustion zone. The modeling of heal transfer effect through cylinder wall was shOwn to be critical for an accurate prediction of cylinder pressure especially at the expansion stroke. Future studies are required on the implementation of multiple combustion zones and a heal transfer model into the code.<br/>
연료로 희석된 오일의 특성변화 및 희석오일이 엔진 요소에 미치는 영향에 대한 실험적 연구
박태식(Tae-Sik Parkf),송봉하(Bong-Ha Song) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
An experimental study was conducted to evaluate characteristic variation of diluted oil by diesel fuel and its effects on engine components. This test was performed on 2700cc, <br/> 5 cylinder, "XDi 270 engine" of Ssangyong Motor Company. Especially, engine oil was made to have 15% fuel content. To predict existing fuel content in oil after test was used the viscosity calibration curve. About half percent of fuel in diluted oil was distillated by various paths related to reciprocation motion of piston and the rest fuel plays an important role for decreasing oil viscosity. <br/> Test results show that lowered oil viscosity by fuel dilution become a reason of increasing engine wear. Therefore, this caused the quantity of blow-by gas to increase and main gallery pressure to decrease.
최현정,방나영,송보완,김남재,류봉하 WHO COLLABORATING CENTRE FOR TRADITIONAL MEDICINE 2004 東西醫學硏究所 論文集 Vol.2004 No.-
In order to investigate to develop the new dosage form of the traditional herbal medicine which have been used for the treatment of disease in oriental medicine, we conducted a survey on 217 patients who visited oriental hospital in Kyung Hee University Medical Centre during one month since October 2003. They were given questionnaires to answer and results of this study were as the following: 1. About 45% patients visited in oriental hospital believed that oriental medicine was better remedy than modern medicine. 2. Most of patients felt that the oriental medical expenses were expensive. 3. About 60% patients preferred the modernized dosage form such as extract powder and granule, etc. rather than medicinal herbs in package. 4. Most of patients hope that decoction of medicinal herbs in package would change the advanced dosage forms such as tablet, capsule and extract powder, Because patients suffered from inconvenience of making a decoction, unhandy, unwieldy and keeping. 5. About 60% patients pointed out that merits of advanced dosage forms of medicinal herbs were convience to take and handy, etc.. However, they had an Intension that there were some difference of efficacy between decoction and modernized dosage forms of oriental medicine. Because of several defects such as unusual flavor and smell, incompatible food, large volume with amount, inconvenience of carrying and decocting oriental herbal medicines, most of patients would expect the development of the advanced dosage forms of them. In summary, this study show that it was needed to develop the new dosage forms of oriental herbal medicine on the basis of scientific research and economical cost of medical expenses.