[論文] 高次 三角形 有限要素에 依한 矩形斷面의 溫度分布와 熱傳達

용호택,서정일,조진호 한국자동차공학회 1981 오토저널 Vol.3 No.3

This paper is studied an efficient temperature distribution and heat transfer of two-dimensional rectangular cross-section by the higher-order triangular finite dynamic element and finite difference.<br/> This is achieved by employing a discretization tcchnique based on a recently developed concept of finite dynamic elernents_[1][2]. involving higher order dynamic correction terms in the associated stiffness and convection matrices.<br/> Numerical solution results of temperature distribution presented herein clearly optimum element and show that FEMIO is the most accurate tcmperature distribution, but heat transfer and computational effort is the most acquired.

유한 요소법에 의한 구형단면의 온도분포와 Computational Effort에 관한 연구

용호택,Yong, Ho-Taek 대한설비공학회 1984 설비저널 Vol.13 No.2

The aims of this study are to obtain a suitable method and a proper mesh for investigation of the temperature distribution and heat transfer. The relative errors of temperature distribution and heat transfer for each mesh are acquired in accordance with linear finite element (FEM 3), square finite element (FEM 6), cubic finite element (FEM 10), and finite difference method (FDM). It has been found that FEM 10 is the most accurate measure to obtain the temperature distribution and heat transfer. However, no significant results have been obtained successfully, because when higher order finite element methods are used the more computational efforts are necessary due to the distribution of elements. The results of this study are as follows ; 1 . In case of a=b=L, meshes for less than $1\%$ relative errors (temperature distribution) acquired in various methods to exact solution are $2\times2,\;4\times4,\;8\times8\;and\;8\tiems8$ for each FEM 10, FEM 6, FEM 3 and FDM and a=L, b=1/2L are $10\times5$ for each FEM 3 and FDM. And the tendency of results acquired of heat transfer is similar to those above. 2 . In computational efforts (a=b=L), FEM 6 has taken 21 times. and FEM 10 154times FEM 3 and FDM and FEM 3 is the sane as FDM.

有限要素法에 의한 三次元 熱傳導 理論解析

龍鎬澤 단국대학교 대학원 1978 學術論叢 Vol.2 No.-

2차원 矩形斷面의 溫度分布와 勾配場에 관한 硏究

용호택 서울産業大學校 1996 논문집 Vol.43 No.1

The aim of this study are to obtain a suitable method for each mesh and temperature gradient field of exact solution. The mean relative errors of temperature distribution and heat transfer for each mesh are acquired with finite linear, square, cubic element and finite difference method. The plot of temperature contour and gradient field are plotted of Biot number 0.1 and 50 about each eigenvalue λn=15. The relative errors of temperature distribution and heat transfer for each mesh are acquired each method. It has been found that cubic finite element is the most accurate measure to obtained. However, no significant results have been obtained successfully, because when higher order finite element methods are used the more computational efforts.

MATLAB과 Mathematica에 의한 타원형 편미분 방정식에 관한 연구

용호택 서울産業大學校 1986 논문집 Vol.50 No.2

The aim of this paper is to find optimized method and relative error-n equation for parabolic partial differential equation. The results of this study are apparent: a)MATLAB and Mathematica formula of Explicit, Implicit finite difference and ADI method is appeared each u(n+1)=Au(n), Bu(n+1)=u(n) and B'u(n)=A'u(n+1), B'u(n+1)=A'u(n+2). b)Parabolic and Elliptic partial differential equation Relative error-n equation are appeared linear. c)The explicit formula are derived which are more oscillated than the implicit and ADI formula for all value n and relative errors.

有限要素法에 依한 矩形斷面의 溫度分布와 熱傳導

용호택(龍鎬澤),서정일(徐廷一),임장순(任將淳) 한국태양에너지학회 1981 한국태양에너지학회 논문집 Vol.1 No.1

This paper studied the temperature distribution and heat transfer at a rectangular cross-section. Particularly, as we have known that FEM6, FEM10 can be able to divide FEM3(25), FEM3(49) and we observed it with the details.<br/> The approximate solutions (FDM,FEM3,FEM3(25),FEM3(49),FEM6) were compared to the 2-dimensional exact solution.<br/> The results of this paper show that FEM6 is the most accurate temperature profiles and heat transfer, furthermore mean values of the FEM6 is more accurate than FEM3(25) and FEM3(49).

吸氣管 內에 空氣噴射가 터보過給디젤機關의 過渡性能改善에 미치는 影響

용호택,전봉준,최낙정 서울産業大學校 産業大學院 1995 大學院論文集 Vol.3 No.-

This study investigates the characteristics of transient response in a turbocharged diesel engine by using the computer simulation with experiments. Experimental study on the engine system is carried out to examine the validity of numerical analysis, and the predicted results are compared with experimental data at various conditions. Further, experiment for improving the low speed torque and acceleration performance is also performed by means of injecting air in the inlet manifold. The effects of air injection on the response performance are investigated at various conditions such as injection pressure, injection period, accelerating time, accelerating rate, load and engine speed.

불꽃 점화 기관에서 흡배기 다기관내 가스 유동에 관한 해석

용호택,주재인,박찬준 서울産業大學校 1993 논문집 Vol.38 No.1

This research is to investigate the characteristics of gas flow in the intake and exhaust manifolds in a S. I. engine. The pressures in intake and exhaust manifolders were measured over range of speed which were varied 2000 rpm to 4000 rpm at WOT. The predictions of pressure variations in intake and exhaust manifolds were made by using the method of characteristic of gas dynamics. The pressure in combustion chamber was also measured to use as the database for the simulation model when the speed of engine was 3500 rpm. The results of predicted and measured pressure in intake and exhaust manifolds had the similar frequency and magnitude over all range of speeds considered. The magnitude of disprepancy between measured and predicted pressure was increased when the speed of engine was increased. The pressure waves in intake and exhaust manifolds had always 4 period in each cycle in spite of varing the speed of engines. The maximum pressures in intake and exhaust manifolds were increased due to the ram effect when the speed of engine were increased.

近似解法에 의한 矩形斷面의 溫度分布와 熱傳達의 平均相對 誤差式에 關한 硏究

龍鎬澤,朱宰寅 서울産業大學校 1986 논문집 Vol.24 No.1

The aims of this study is to obtain mean relative error's equations of temperature distribution and heat transfer against mesh increments. The mean relative errors of internal, adiabatic and convectional model points(Table 1, 2, 3) are acquired in accordance with linear finite element(FEM 3), square finite element(FEM 6), cubic finite element (FEM 10) and finite difference method (FDM). And the correlation coefficient is calculated by the use of the Table 1, 2 and 3. It has been found that the cubic log equations is the most accurate measures to obtain the temperature distribution and heat transfer.

Pt-Rh을 사용하는 自動車用 三元觸媒裝置의 정화機能

용호택,한경 서울産業大學校 1993 논문집 Vol.38 No.1

This paper is about the experiment on the activation of automotive three-way catalyst with Pt-Rh. The comparative experiment on the AA9-163 catalyst and the catalyst which is a different content and content and ratio of Pt-Rh. The comparative experiment on the AA9-163 catalyst taken off from the automobiles which was driven the regular distance with the different fuel and a brand-new. The L/O temperature and the characteristic of the three-way purification with the gas-activation was the measured by measuring instrument. There was no change in the active efficiency of the catalyst if Pt-Rh in the catalyst is more than the regular amount. In the case of the car, after driving the distance of 75000km, the efficiency of the catalyst dropped off 50%, Even if the car is driven only 2000km with the leaded fuel, the purifying efficiency of HC and NOx was deprived because of the lead poisoning.