• Title/Summary/Keyword: energy balance model

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Effect Analysis on Energy Efficiency Improvement for Establishing Energy Balance Flow (Energy Balance Flow 구축에 의한 에너지효율향상 효과분석)

  • Kim, Yong-Ha;Jo, Hyun-Mi;Sin, Hyung-Chul;Kim, Hyung-Jung;Woo, Sung-Min;Kim, Young-Gil
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.679-680
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    • 2011
  • This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

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The Prognostic Model for the Prediction of the Road Surface Temperature by Using the Surface Energy Balance Theory (지표면 에너지 수지 이론을 이용한 도로노면온도예측을 위한 예단 모델 개발)

  • Song, Dong-Woong
    • Journal of the Korean Geotechnical Society
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    • v.30 no.11
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    • pp.17-23
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    • 2014
  • In this study, the prognostic model for the prediction of the road surface temperature is developed using the surface energy balance theory. This model not only has a detailed micro meteorological physical attribute but also is able to accurately represent each surface energy budget. To verify the performance, the developed model output was compared with the German Weather Service (DWD)'s Energy Balance Model (EBM) output, which is based on the energy budget balance theory, and the observations. The simulated results by using both models are very similar to each other and are compatible with the observed data.

A study on Development of Korean - Energy System Management Model for Effect Analysis of Integrated Demand Management (통합수요관리 효과분석을 위한 한국형 Energy System Management 모형 개발에 관한 연구)

  • Kim, Yong-Ha;Jo, Hyun-Mi;Kim, Ui-Gyeong;Yoo, Jeong-Hui;Kim, Dong-Gun;Woo, Sung-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1103-1111
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    • 2011
  • This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

A many-objective optimization WSN energy balance model

  • Wu, Di;Geng, Shaojin;Cai, Xingjuan;Zhang, Guoyou;Xue, Fei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.2
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    • pp.514-537
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    • 2020
  • Wireless sensor network (WSN) is a distributed network composed of many sensory nodes. It is precisely due to the clustering unevenness and cluster head election randomness that the energy consumption of WSN is excessive. Therefore, a many-objective optimization WSN energy balance model is proposed for the first time in the clustering stage of LEACH protocol. The four objective is considered that the cluster distance, the sink node distance, the overall energy consumption of the network and the network energy consumption balance to select the cluster head, which to better balance the energy consumption of the WSN network and extend the network lifetime. A many-objective optimization algorithm to optimize the model (LEACH-ABF) is designed, which combines adaptive balanced function strategy with penalty-based boundary selection intersection strategy to optimize the clustering method of LEACH. The experimental results show that LEACH-ABF can balance network energy consumption effectively and extend the network lifetime when compared with other algorithms.

A Modification of Departure from Nucleate Boiling Model Based on Mass, Energy, and Momentum Balance For Subcooled Flow Boiling in Vertical Tubes

  • Sul, Young-Sil;Lee, Kwang-Won;Ju, Kyong-In;Cheong, Jong-Sik;Yang, Jae-Young
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05b
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    • pp.108-113
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    • 1996
  • Several analytical models for the departure from nucleate boiling (DNB) phenomenon have been developed during the last decade. Among these, Chang & Lee's model based on a bubble crowding mechanism is remarkable in the fundamental features characterized as the formulation of mass, energy, and momentum balance equation at thermal-hydraulic conditions leading to the DNB. However, Bricard and Souyri remarked that the assumption of stagnant bubbly layer at the DNB condition is questionable and the signs on the axial projections of the momentum fluxes at the core/bubbly layer interface in the momentum balance equations are erroneous. From this remark, Chang & Lee's model has been re-examined and modified by correcting the erroneous treatments in the momentum balance equations and removing the spurious assumptions. The revised model predicts well the extensive DNB data of water in uniformly heated tubes at low qualities and shows more accurate prediction compared with the original model.

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The Effect of Building Morphology on Sea Breeze Penetration over the Kanto Plain - Analysis of Mean Kinetic Energy Balance of Moving Control Volume along Sea Breeze -

  • Sato, Taiki;Ooka, Ryozo;Murakami, Shuzo
    • International Journal of High-Rise Buildings
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    • v.1 no.2
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    • pp.73-80
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    • 2012
  • In order to use sea breezes to counter the heat island phenomena, i.e. to promote urban ventilation, it is necessary to clarify the effect of building morphology and height on large-scale wind fields. In this study, the sea breeze in the vicinity of the Kanto Plain in Japan is simulated using a mesoscale meteorological model incorporating an urban canopy model, and the inland penetration of sea breezes is accurately reproduced. Additionally, a mean kinetic energy balance within a domain (Control Volume; CV) moving along the sea breeze is analysed. From the results, it is clarified that the sea breeze is interrupted by the resistance and turbulence caused by buildings at the centre of Tokyo. The interruption effect is increased in accordance with the height of these buildings. On the other hand, adverse pressure gradients interrupt in the internal region.

Determination of shear stiffness for headed-stud shear connectors using energy balance approach

  • Ye, Huawen;Huang, Ruosen;Tang, Shiqing;Zhou, Yu;Liu, Jilin
    • Steel and Composite Structures
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    • v.42 no.4
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    • pp.477-487
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    • 2022
  • The shear stiffness of headed-stud shear connectors has no unified definition due to the nonlinear characteristics of its load-slip relationship. A unified framework was firstly adopted to develop a general expression of shear load-slip equation for headed-stud shear connectors varying in a large parameter range based on both force and energy balance. The pre- and post-yield shear stiffness were then determined through bilinear idealization of proposed shear load-slip equation. An updated and carefully selected push-out test database of 157 stud shear connectors, conducting on studs 13~30mm in diameter and on concretes 30~180 MPa in cubic compressive strength, was used for model regression and sensitivity analysis of shear stiffness. An empirical calculation model was also established for the stud shear stiffness. Compared with the previous models through statistical analysis, the proposed model demonstrates a better performance to predict the shear load-slip response and stiffness of the stud shear connectors.

Analysis of Energy and Material Balance in Smelting Process of Waste Sand (폐주물사의 용융공정에서의 물질 및 에너지 수지의 해석)

  • Chung, Won-Sub;Min, Dong-Jun;Yoon, Su-Jong
    • Journal of Korea Foundry Society
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    • v.15 no.5
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    • pp.477-482
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    • 1995
  • A computer simulation model of various smelting process for melting waste sand was developed by using energy and material balance concept. This model can predict the coal, flux and oxygen consumption and the volume and temperature of off-gas. The major critical variables for smelting process can be explained by using the analysis of energy and material balance. The major conclusions were as follows; 1. The most important variables for smelting process were high post-combustion ratio, high heat transfer efficiency and refractory protection technology. 2. For saving energy in this smelting process, selection of raw materials i.e coal, flux are very important, espacially using of low volatile coal is very profitable. 3. The treatment cost of waste sand is high and environmental restriction is severe, in this reason we must be concerned in the treatment of waste sand by smelting process.

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Evaluation of Computational Fluid Dynamics for Analysis of Aerodynamics in Naturally Ventilated Multi-span Greenhouse

  • Lee, In Bok;Short, Ted H.;Sase, Sadanori;Lee, Seung Kee
    • Agricultural and Biosystems Engineering
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    • v.1 no.2
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    • pp.73-80
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    • 2000
  • Aerodynamics in a naturally ventilated multi-span greenhouse with plants was analyzed numerically by the computational fluid dynamics (CFD) simulation. To investigate the potential application of CFD techniques to greenhouse design and analysis, the numerical results of the CFD model were compared with the results of a steady-state mass and energy balance numerical model. Assuming the results of the mass and energy balance model as the standard, reasonably good agreement was obtained between the natural ventilation rates computed by the CFD numerical model and the mass and energy balance model. The steady-state CFD model during a sunny day showed negative errors as high as 15% in the morning and comparable positive errors in the afternoon. Such errors assumed to be due to heat storage in the floor, benches, and greenhouse structure. For a west wind of 2.5 m s$^{-1}$ , the internal nonporous shading screens that opened to the east were predicted to have a 15.6% better air exchange rate than opened to the west. It was generally predicted that the presence of nonporous internal shading screens significantly reduced natural ventilation if the horizontal opening of the screen for each span was smaller that the effective roof vent opening.

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Efficient Energy Management for Pyro-processing of Solids - (1) Heat & Mass Balance and Evaluation (고체 고온공정에서 효율적 에너지 관리 - (1) 공정 열정산 및 평가 방법)

  • Ha, Daeseung;Choi, Sangmin
    • Journal of the Korean Society of Combustion
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    • v.21 no.1
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    • pp.18-30
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    • 2016
  • Pyro-process of solids is the way to heat solid materials under high temperature. In this processing, energy efficient use is one of the main concerns due to its high energy consumption of bulk materials. To calculate the energy use of processes, heat & mass balance in simplified 0-dimensional model was performed. Energy calculation by this simplified model can lead to confusion due to simplification. Thus, it is necessary to understand considerations of energy analysis. In this study, cement manufacturing as a very common example of pyro-processing of solids, was introduced for explaining considerations of energy analysis for energy efficient use.