• Title/Summary/Keyword: Heating ratio

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An Analysis on the 500m - Mesh Classification based on the Heat Consumption Density in Busan (부산시 500m 메시 레벨에서의 에너지소비량 분포 분석)

  • Hwang, Kwang-Il;Choi, Duk-In;Kim, Da-Hye;Yang, Ing-Chan;Yoon, So-Ra
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2010.04a
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    • pp.193-194
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    • 2010
  • This study classify the every meshes in Busan metropolitan city, based on the heat density and cooling/heating ratio. As the result of evaluations on the heat density and cooling/heating ratio for the 3289 meshes, the number of meshes which needs more than 2.5 Tcal/mesh.year of heat density is 850(25.8%). The meshes that needs more than district and cooling index 1, which is normally and strongly requested to introduce the district cooling and heating system, is 188(5.7%).

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Effect of Heating Conditions on the Resistant Starch Formation (가열방법에 따른 효소저항전분 생성)

  • Lee, Shin-Kyung;Mun, Sae-Hun;Shin, Mal-Shick
    • Applied Biological Chemistry
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    • v.40 no.3
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    • pp.220-224
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    • 1997
  • As corn starches with different amylose content were heated at different temperature $(100^{\circ}C,\;121^{\circ}C)$ with starch / water ratio (1:3.5, 1:9) and heating-cooling treatment was repeated up to 4 times, the yield of RS(resistant starch) from heated corn starches was investigated by the enzymatic-gravimetric method and the ${\alpha}-amylase$ treatment. Compared to ${\alpha}-amylase$ method, enzymatic-gravimetric method was more effective to hydrolyze the amorphous region of heated corn starch. With increasing the amylose content and the number of heating-cooling treatment, the yield of RS increased, regardless of isolation method. Heated corn starches formed at $121^{\circ}C$ provided higher yield of RS than those formed at $100^{\circ}C$. Higher RS yield was also observed in the case of starch/water ratio (1:3.5) compared to the case of ratio (1:9).

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An Experimental Study on the Performance Characteristics of a Heat Pump System in the Heating Operation Mode with the Hot Gas Bypass (열펌프의 난방운전시 핫가스 바이패스에 따른 성능 특성에 관한 실험적 연구)

  • Ahn, Jae-Hwan;Joo, Young-Ju;Cho, Il-Yong;Kang, Hoon;Kim, Yong-Chan;Choi, Jong-Min
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.539-543
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    • 2009
  • When the suction pressure of compressor decreases under its limit, the compression ratio is increased causing the malfunctions of compressor. As the method to decrease the compression ratio, hot gas bypass system is usually adopted in heat pump system. In the hot gas bypass system, the discharged gas from the compressor is bypassed into the compressor suction, which causes the increase of suction pressure and the decrease of compression ratio. In this study, the characteristics and performances of the hot gas bypass system in heat pump was investigated experimentally with a variation of the bypass flow rate ratio. With the increase of the bypass rate ratio, the compressor suction pressure was increased, even though the total capacity and COP was decreased. From the analysis of the experimental results, the optimum pressure control algorithm was suggested in this study.

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A study on the Estimation of Standard Heating City Gas Consumption of Apartment Housing (공동주택의 난방용 도시가스 표준사용량 산정에 관한 연구)

  • Shim, Yun-Hee;Choi, Chang-Ho;Lee, Hyun-Woo
    • Journal of the Korean Solar Energy Society
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    • v.26 no.3
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    • pp.89-97
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    • 2006
  • Our Housing culture continuously changes for the correspondence to social development and changes of economy, and be developing. A massive apartment complex continuously increased, and According to this in our country heating energy consumption of a residential building is continuously increasing at country me whom was limited in order to raise efficient residential land use and diffusion ratio of house. If confirm an element to be able to reduce use of a heating energy, and there is saving possibility to parts of energy saving, this study will present the standard amount used with bases to the gas amount used for heating and Field Test data about room temperature. Execute simulation with building balance (public area, a plain), the gas amount useds such as incense of a building, indoor setting temperature ($^{\circ}C$), a position of an apartment house etc. to affect the energy amount used of a valuation object building of a variable through Field Test and research on the actual condition. Calculate the standard amount used of city gas for winter season heating of a comparative analysis apartment house to data value getting the above results through Field Test and simulations with bases.

Preparation of Heating Fuel by the Recycling of High Viscosity Waste Oil (고점도 폐유의 재활용에 의한 난방연료 제조)

  • Jin, Eui;Chung, Yeong-Jin
    • Applied Chemistry for Engineering
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    • v.20 no.4
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    • pp.411-415
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    • 2009
  • To replace waste oil with the lowest grade which has high viscosity into heating fuel, light oil and buncker C oil in waste oil was used and the fuel characteristic was analyzed by its concentration after mixing oil. The mixture conditions were controlled by the reaction time (30 s~30 min) and kept by the reaction temperature ($75{\pm}5^{\circ}C$) when mixing speed was stirred at 3400~3600 rpm. We used the buncker C oil and light oil to decrease viscosity of waste oil and the dynamic viscosity was decreased by 81~96%. Optimum mixing ratio (waste oil : buncker C oil : light oil) as heating fuel was 1 : 1 : 1. Flash point, dynamic viscosity and heating value of this case were identified $78^{\circ}C$, $20.02mm^{2}/s$, 9158 kcal/L respectively.

A study on the efficiency of sloped type Double-skin System for the Curtailment of Heating/Cooling Load (냉난방부하 절감을 위한 경사형 이중외피시스템의 성능연구)

  • An, Hyung-Jun;Kim, Young-Tag;Choi, Chang-Ho;Lee, Hyn-Woo
    • Journal of the Korean Solar Energy Society
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    • v.24 no.4
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    • pp.77-87
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    • 2004
  • BIPV or double skin applied to the surface of the building, power and thermal load cannot both be increased. In the case of BIPV, because it is applied to the facade, incident solar energy decreases and efficiency drops off. The system in this paper complements these disadvantages and aims to decrease the heating & cooling load by transforming solar energy to electronic and thermal energy. The research in this paper is about the applicability of the clear PV attached double-skin system. And the PV electronic generation and the factors that affect the heating & cooling load such as the daily radiation, sun shading ratio, heating & cooling load, daylight luminance and glare distributions in the building are simulated.

Numerical & Experimental Study For Burner of Low NOx Formation of Multi-Stage In a Combustor (연소기에서의 다단 저 NOx 버너의 수치 및 실험적 연구)

  • Choi, Yun-Ki;Kang, Kyung-Tae;Kim, Young-Mo
    • 한국연소학회:학술대회논문집
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    • 2003.12a
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    • pp.65-74
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    • 2003
  • Air pollution included Nitric Oxide(NOx) from heating boilers is increased by pursuing better life. Development of low NOx emission boiler is strongly needed. However commercial burner for heating boiler is also asked to be thermal efficient and low-cost manufactuable in addition to low NOx emission. Small space for combustor including burner is usually allowed. In this study, parametric study of compact low NOx burner for heating boiler was done using numerical analysis and experiments. Commerical computational fluid dynamic(CFD) program named CFX 5-6 was used for numerical analysis of low NOx burner using turbulent diffusion flame. Comparison of outlet NO and outlet temperature under various equivalence ratio and fuel flow rate was performed between experiment and numerical analysis.

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Experimental Study on the Radiative and Convective Cooling of Electronic Modules opposed to a Heated Vertical Plate (가열 수직 평판과 마주보는 전자모듈의 복사 및 대류 냉각에 대한 실험적 고찰)

  • Choi, In-Su
    • Journal of the Korean Society of Industry Convergence
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    • v.8 no.2
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    • pp.105-112
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    • 2005
  • The characteristics of natural convection heat transfer combined with radiation in a vertical parallel plates has been investigated experimentally. The vertical channel is consisted with a heated wall and three protruding heating sources attached on the opposite wall. The cooling of modules has been experimented with heating the wall as well as modules themselves at different aspects ratios and heating fluxes. As the location of module is higher, the temperature becomes higher, but the increasement is smaller. When the aspect ratio is lower than 26, its effect on the temperature is not significant rather than that of the radiation heat transfer. Furthermore, the correlation of Nusselt number with the Rayleigh number are attempted, but additional treatment is needed to accomodate the cases of heating module and/or opposite wall.

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Textural Properties of Cowpea Mook as Affected by Heating Conditions (가열조건에 따른 동부묵의 텍스쳐 특성)

  • 김성곤;이애랑
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.4
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    • pp.659-663
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    • 1998
  • Mook is a traditional Korean food made from the sediment of mungbean, cowpea, buckwheat or acorn. The air-dried sediment of cowpea(6~9%, dry basis) was heated to 80~95$^{\circ}C$ by continuous(method A) or instantaneous(method B) heating method and held at that temperature for 20min and then cooled at 15$^{\circ}C$ for 3hrs. The optimum deformation rate for the measurements of hardness and cohesiveness of cowpea mook by Instron Universal Testing Machine was 55~65% by method A and 60~70% by method B. The hardness of mook made by method A was the highest at heating temperature of 9$0^{\circ}C$, whereas that by method B was linearly decreased as the heating temperature increased at all concentrations. The mook made by method B had higher cohesiveness than that by method A. The ratio of cohesiveness to hardness was also higher in mook made by method B.

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Effect of Heating on the Sex Maturation and Egg Development of the Ark Shell, Scapharca Subcrenata (가온사육에 의한 새꼬막, Scapharca subcrenata의 성 성숙 및 난 발생)

  • Jung, Choon-Koo;Oh, Bong-Se;Kim, Tae-Ik;Jin, Young-Guk
    • The Korean Journal of Malacology
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    • v.26 no.3
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    • pp.201-209
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    • 2010
  • The investigated of survival rate, sex ratio, condition index, gonad development frequency, gonad index, fertilization rate, hatching rate and time required development of D shape larvae of the ark shell, Scapharca subcrenata. Survival rate was lower in heating group compared with control group (P < 0.05). Sex ratio (female:male) observed 1:0.97 in control group, 1:0.62 in heating group. Condition index was significantly higher in heating group than control group (P < 0.05) and higher increased more than water temperature $17^{\circ}C$ of heating group. Gonad development observed slow in control group but more than ripe stage 80% in heating group (21-28 day, $20^{\circ}C$). Gonad index was higher in heating group compared with control group (P < 0.05). Fertilization rate and hatching rate of the ark shell was observed $82.17{\pm}3.55%$ and $63.57{\pm}2.36%$, respectively. The time required development of D shape larvae of the ark shell was observed 15 hour after fertilization. The suggested that results of the ark shell by heating were effective sex maturation and normal egg development.