• Journal of Nutrition and Health
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• 제1권1호
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• pp.33-36
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• 1968

Amounts of heat production determined by two indirect calorimetric methods, i.e., respiration-calorimetric method and body balance method were compared. In this report the apparatus, its operation and computation procedures for Haldane respiration-calorimetry modified by Han as well as procedures for body balance method are described. It was found that the heat production measured by two methods are similar.

• KEPCO Journal on Electric Power and Energy
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• 제5권3호
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• pp.181-188
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• 2019

본 연구에서는 발전시스템의 설계 입출력변수들을 Heat & Mass balance 계산 solver 및 최적화 알고리즘과 연계하고 반복계산 과정을 자동화함으로써 기술 및 경제적 측면을 고려한 최적의 발전시스템 Heat & Mass balance 설계를 도출하는 최적설계 자동화 기법을 개발하였다. 그리고 이에 대한 효과를 분석하기 위하여 발전소 형식별 10종에 대하여 최적설계 기법을 적용한 결과, NPV 및 IRR에 대한 개선 효과를 기대할 수 있었다.

• 대한기계학회논문집
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• 제7권4호
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• pp.417-424
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• 1983

This paper presents two methods of obtaining approximate analytic solutions for the temperature distributions and heat flow to two-dimensional transient heat conduction problems in a finite strip with constant thermal properties using the Heat Balance Integral. The methods introduced in this study are as follows; one using the Heat Balance Integral only, and the other successively using the Heat Balance Integral and an exact analytic method. Both methods are applicable to a large number of the two-dimensional unsteady conduction problems in finite regions such as extended surfaces with uniform thickness, but in this paper only solutions for the unsteady problems in a finite strip with boundary condition at the base expressed in terms of step function are provided as an illustration. Results obtained by both methods are compared with those by the exact two-dimensional transient analysis. It is found that both approximate methods generate small time solutions, which can not be obtained easily by any exact analytic method for small values of Fourier numbers. In the case of applying the successive use of the Heat Balance Integral and Laplace transforms, the analysis shows good agreement with the exact solutions for any Fourier number in the range of Biot numbers less than 0.5.

• 한국환경과학회지
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• 제24권6호
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• pp.721-729
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• 2015

Surface heat balance of the Gangjeong-Goryung Reservoir is analyzed for 12-17 August 2013. Each flux elements at the water surface is derived from the special field observations with application of an aerodynamical bulk method for the turbulent heat fluxes and empirical formulae for the radiation heat fluxes. The rate of heat storage in the reservoir is estimated by using estimated by surface heating rate and the vertical water temperature data. The flux divergence of heat transport is estimated as a residual. The features of the surface heat balance are almost decided by the latent heat flux and the solar radiation flux. On average for 12-17 August 2014 in the Gangjeong- Goryung Reservoir, if one defines the insolation at the water surface as 100 %, 94 % is absorbed in the reservoir; thereafter the reservoir loses about 30~50% by sensible heat, latent heat and net long-wave radiation. The residue of 50~80 % raises the water temperature in the reservoir or transported away by the river flow during the daytime.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.595-600
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• 1993

The heat of reaction has been estimated from heat balance relationships around the reactor. The heat balance equations were formulated with the assumptions that the reactor temperature is uniformly distributed and the jacket temperatures are axially distributed. We have obtained the temperature distribution of jacket contents by FDM. And then, we have rearranged the heat balance equations so that the heat of reaction can be estimated from the finite number of temperature measurements, i.e., temperatures of the reactor contents, at the jacket inlet and outlet, respectively. The proposed method for reaction heat estimation on were applied to industrial batch reactors ; one is ABS polymerization reactor and the other is SAN polymerization reactor. We have also examined the variation of overall heat transfer coefficients for the reactors during reaction.

• 대한설비공학회지:설비저널
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• 제11권3호
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• pp.1-8
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• 1982

When exact analytical solutions to certain type of heat conduction problems are quite cumbersome or not obtainable, it is important to introduce approximate analytical methods which are simple and useful compared with numerical methods. In this study, therefore, the Heat Balance Integral Method is applied to analysis of steady-state conduction in a straight fin of trapezoidal profile, and the two-dimensional temperature distribution in the fin and the approximate fin efficiency are obtained. Results are compared with those by the one- dimensional analysis and two-dimensional numerical analysis for a wide range of Biot numbers. It is shown that the two-dimensional temperature distribution obtained by the integral method is in good agreement with that by the finite element method at Biot numbers for which the result by the one-dimensional analysis is unreliable.

• 한국환경과학회지
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• 제4권3호
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• pp.197-206
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• 1995

Surface heat balance of the northern sea of Cheju Island for summer in 1993 and 1994 is analyzed using the observation data obtained by Marine Research Institute, Cheju National University. Each flux elements at the sea surface is derived from the marine meteorological reports with application of an aerodynamical bulk method for the turbulent heat fluxes, and empirical formulae for the long-wave radiation heat fluxes. The flux divergence of oceanic heat transport and the rate of heat storage in the ocean are estimated as residual. The features of the surface heat balance are mainly decided by the solar radiation flux and the latent heat flux for 199B. But the Bowen Ratios were large for 1993. This means that the sensible heat fluxes were nearly equal to the latent heat fluxes for 1993. In this period, mean flux divergence of oceanic heat transport is about 130 W/$m^2$.

• 수산해양교육연구
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• 제25권1호
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• pp.192-197
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• 2013

To overcome the mismatch of heat demand and heat supply is important as considering point on heat utilizing aspects in Urban area. At this point, It need to know the plan of heat networks on the heat balance aspects. The purpose of this study is to know the method of heat evaluation on heat network around costal area. It is need to building uses to calculate the amounts of heat demand. 25 different types of building uses were supplied, but it was reclassified 10 types and calculated the amounts of heat demand in the costal area. The results was described on the area with GIS mapping.

• 한국도로학회논문집
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• 제17권5호
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• pp.1-10
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• 2015

PURPOSES : A finite difference model considering snow melting process on porous asphalt pavement was derived on the basis of heat transfer and mass transfer theories. The derived model can be applied to predict the region where black-ice develops, as well as to predict temperature profile of pavement systems where a de-icing system is installed. In addition, the model can be used to determined the minimum energy required to melt the ice formed on the pavement. METHODS : The snow on the porous asphalt pavement, whose porosity must be considered in thermal analysis, is divided into several layers such as dry snow layer, saturated snow layer, water+pavement surface, pavement surface, and sublayer. The mass balance and heat balance equations are derived to describe conductive, convective, radiative, and latent transfer of heat and mass in each layer. The finite differential method is used to implement the derived equations, boundary conditions, and the testing method to determine the thermal properties are suggested for each layer. RESULTS: The finite differential equations that describe the icing and deicing on pavements are derived, and we have presented them in our work. The framework to develop a temperature-forecasting model is successfully created. CONCLUSIONS : We conclude by successfully creating framework for the finite difference model based on the heat and mass transfer theories. To complete implementation, laboratory tests required to be performed.

• 동력기계공학회지
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• 제11권1호
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• pp.70-75
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• 2007

Heat transfer coefficient and fin efficiency of a heat exchanger dispersed in the microelement of control volume were predicted with various flow patterns, conditions and material properties. A computational program was developed by using the method of efficiency-NTU(Number of transfer unit). The modelling was applied to heat exchangers, also was integrated in power pack cooling system in an armored vehicle. The compatibility and the generality were proved by comparing the prediction values with the test results. The developed program may be useful for the design of the cooling system in an armored vehicle.