팽창율이 일정한 초음속 노즐흐름의 응축개시에 관한 연구

김병지,권순범,이은수 대한기계학회 1990 대한기계학회논문집 Vol.14 No.2

A rapid expansion of moist air of condensible gas through a supersonic nozzle gives rise to condensation of nonequilibrium and equilibrium processes. Because most of the effects of condensation on the flow are caused by process of nonequilibrium condensation, it is very important to know the onset. condition of nonequilibrium condensation. In the present study, the relation between the initial relative stagnation humidity and the onset Mach number, for the case of the similarity law suggested by Zierep and Lin. Furthermore, the present theoretical result number is compared with the experimental, numerical and other results.

응축을 수반하는 정상 2차원 초음속 노즐유동의 수치해석

김병지 가톨릭상지전문대학 1997 논문집 Vol.27 No.1

For the supersonic circular nozzle flow with condensation the effect of the stagnation specific humidity on the quantity of state and the condensation shock wave is investigated by numerical analysis and experiment the results are summarized as follows ; The nonequilibrium condensation zone glove form to two dimensional shape with the of felt of geometry. The increase of the stagnation specific humidity escalate the extent of its zone. The condensation shock wave is located in the nonequilibrium condensation zone, its location moves to the upstream and its shape becomes gradually to normal condensation shock wave, with the increase of the stagnation specific humidity. It is confirmed that the point of onset of nonequilibrium condensation be corresponded to the point where the static pressure deviates from that of isentropic process and the nucleation rate is maximum.

팽창률이 일정한 초음속 노즐흐름의 응축개시에 관한 연구

김병지,권순범,강창수,이은수 대한기계학회 1989 대한기계학회 춘추학술대회 Vol.- No.-

영각을 가진 미소진폭 파형벽을 통한 응축을 수반하는 초음속 유동

김병지 가톨릭상지대학 사회개발·산업기술연구소 1999 論文集 Vol.29 No.-

미소진폭 파형벽을 따라 응축성 기체인 습공기가 초음속으로 흐르는 경우 미소진폭 파형벽의 중심선이 주류에 대하여 임의의 영각을 가질 때의 유동장에 대한 유동특성을 구명하고자 파형벽에 의한 경사충격파의 발생, 정체점 상태량이 유동특성에 미치는 영향, 영각에 의한 유동특성의 변화 등을 고찰하였다. 초음속 풍동, 슈리렌 시스템 및 수은 마노메타 등의 실험장치를 이용하고, 가시화 사진 및 정압측정으로부터 실험결과를 얻었다. 또한, 응축을 고려한 직접진행형 특성곡선법에 의한 수치해석을 수행하였고, 실험결과와 비교함으로써 정체점 상태량과 영각의 변화에 따른 경사충격파의 거동과 유동장 상태량의 변화를 확인하였다. Supersonic flow with condensation are of great importance in diverse fields of science and engineering such as high speed aircraft, rocket nozzle, combustion chamber of gas turbine, ram jets, steam turbine cascades, and so on. Condensation in supersonic flow give rise to the corrosion and erosion, degradation of mechanical components and equipments, as well as efficiency reduction and energy losses in steam turbine cascades. The characteristics of supersonic flow with condensation along a wavy wall of small amplitude with an attack angle in a channel was studied numerically and experimentally. Flow properties in the flow field was calculated by the direct marching method of characteristics. The very complex problem that may appear where the overlapping of the same family characteristics occurs, can be satisfactorily solved by means of the modified method suggested by Zucrow. Intermittent indraft supersonic wind tunnel was used as an experimental apparatus. The flow field was visualized by schlieren system. Static pressure distribution was measured by Hg-manometer and flow properties were obtained by the assumption of isentropic process. Especially, the dependency of the locations of reflection of oblique shockwave generated by the wavy wall, and distributions of flow properties in the flow field, upon the stagnation conditions and attack angles was clarified.

佛敎의 社會·經濟倫理思想 硏究

김병지 동국대학교 불교대학원 1994 佛敎大學院 論叢 Vol.2 No.-

So-called modern industrial society enjoys material abundance in virtue of high economic growth however, on the hand the warning that loss of humanity and seriously threatened even the human existence itself such as due to destruction of natural environment or ecosystem has considerably persuasive power recently. This study was started from the problematic consciousness what the Buddhism could do as we are confronting to the new and imminent situation at this moment. I looked back first the three thoughts as largely divided into equality thought, charity thought and requital thought from "the basic thought of Buddhism about the social ethics" and the Buddha was not recognized inequality under reason whatsoever and I could acknolwedge that he had equally recognized dignity and value of human being and that he was the first man in history who advocated ideology of equality by own sense in Chapter I.Secondly, in the charity thought he e.plained for practical side of ethics of original thought of Buddhism by advocating the comprehensive mercy to every lining creature. In the requital thought by advocating the comprehensive mercy to every living creature. In the requital thought by third, it is fundamentally standing into the equality ideology and that also makes inside and outside with the spirit of mercy. Since therefore, the equality and the mercy thought is nothing but regarding from different angle and there is an independent aspect to speak it from the socio-ethical aspect on the other hand. This is the meaning that we have to stand on the understanding that we aware and feel the favor more internally and spiritually not to return the favor have had in merely formal or mechanical meaning. This has based upon the thoery of connection as fundamental Buddhismic thought and has developed to virtue of the Mahayanist Buddhism also has meaning of occupational ethics which brings increase in productivity as a result of being moral obligation to the community by the labour voluntarily. In Chapter Ⅱ of "the economic ethical thought of Buddhism" I proceeded the study by discussion of details as ① Production theory, ② Distribution theory, ③ Consumption theory, ④ Occupational theory and ⑤ Effective using theory of the goods. As a result the Buddhism has recognized indirect economic deed through production and distribution of spiritual value as to the person of priesthood left from home and positively encouraged every economic deed to those who are at home. By the teaching of Buddhist has not to have purposo to all the economic deeds itselves but it has as means of ascetic e.ercises for emancipatiion. Since therefore, I could aware that the goods may indicate its efficiency through donation and contribution only. As shown on the above I could aknowledge that the Buddhism ont only has foundation of social thought of practice as hinting in the modern crisis circumstance but has presented economic thought of new respect of men especially, with reconsideration of the stiff social sciences or economics today. This study was reviewed the basic position of social and economic ethical thoughts only that is indicated in the Buddhism and deeper study to establish plans and measures about the practical problems with more pariculars must be kept progressed.

미소진폭 파형벽을 가진 유로내에서 凝縮을 수반하는 超音速 유동의 特性 - 수치해석 결과

김병지,권순범 대한기계학회 1992 대한기계학회논문집 Vol.16 No.10

본 연구에서는 미소진폭의 파형벽을 가진 유로내에 응축성 기체인 습공기가 초음속으로 흐르는 경우의 유동에 대하여 정체점에서의 상대습도와 온도의 변화에 따 른 유동장내의 상태량의 변화와 경사충격파의 거동 등을 2차원 수직해석을 통하여 규 명하였다. The characteristic of supersonic flow with condensation along a wavy wall of small amplitude in channel is investigated through the direct marching method of characteristics. The very complex problem that may appear where the overlapping of the same family characteristics occurs, can be satisfactorily solved by means of the modified method suggested by Zucrow. In the present study for the case of supersonic moist air flow, the dependency of location of formation and reflection of oblique shock wave generated by the wavy wall, and the distributions of flow properties, on the relative humidity and temperature at the entrance of wavy wall is clarified by plots of streamline, ios-Mach umber and ios-flow properties. Also, it is confirmed that the wavy wall plays an important key role in the formation of oblique shock wave, and that the effect of condensation on the flow field appears apparently.

[전문대학교 소개] 가톨릭상지대학 자동차계열 소개

김병지(Byung Ji Kim) 한국자동차공학회 2003 오토저널 Vol.25 No.4

미소 진폭 파형벽을 가진 유로내에서 凝縮을 수반하는 定常 2次元 超音速 流動

權純範,金丙知,安亨濬 慶北大學校 1992 論文集 Vol.52 No.-

The characteristic of the steady two-dimensional supersonic flow with condensation along a wavy wall of small amplitude in channel is investigated through the direct marching method of characteristics. The very complex problem that may appear where the overlapping of the same family charateristics occurs, can be satisfactorily solved by means of the modified method suggested by Zucrow. In the present study for the case of supersonic moist air flow, the dependency of location of formation and reflection of oblique shock wave generated by the wavy wall, and distributions of flow properties, on the relative humidity and temperature at the entrance of wavy wall is clarified by plots of frozen Mach number and iso-flow properties. Also, it is confirmed that the wavy wall plays an important key role in the formation of oblique shock wave, and that the effect of condensation on the flow field appears apparently.

波形壁 流路내에서 凝縮이 수반되는 超音速유동에 대한 硏究

권순범,김병지,김흥균 대한기계학회 1994 대한기계학회논문집 Vol.18 No.2

The characteristics of supersonic flow with condensation along a wavy wall of a small Smplitude in a channel is investigated experimentally and numerically. In the present study for the case of supersonic moist air flow, the dependency of location of reflection of oblique shock wave generated by the wavy wall, and the distributions of flow properties in the flow field, on the stagnation relative humidity and temperature is clarified by the plots of streamline, iso-Mach number and iso-flow properties of numerical result and the schlieren photographs of experiment. And. experimental and numerical results are in good agreement.

미소 진폭 파형벽을 가진 유로내에서 응축이 수반되는 초음속유동의 Prandtl-Meyer 팽창에 관한 실험적 연구

권순범,안형준,김병지,선우은 경북대학교 산업기술연구소 1993 産業技術硏究誌 Vol.21 No.-

The characteristics of the Prandtl-Meyer expansion of supersonic flow with condensation through a channel with a small amplitude wavy wall are investigated experimentally. In the present study, for the case of moist air flow in the type of indraft supersonic wind tunnel, the dependency of formation and reflection locations of the oblique shock wave and the distribution of flow properties are clarified by flow visualization and pressure measurement with the variation of the specific humidity and temperature at the entrance of the wavy wall and the attack angle of the wavy wall to the main stream. Also, we confirm that the wavy wall plays an important key role in the formatio of oblique shock wave, and that the effect of condensation on the flow field appears apparently.