http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
열교환기용 외경 9.52㎜ 마이크로휜 관의 고성능화 및 경량화에 관한 연구 : 증발 열전달 특성
임용빈(Yongbin IM),하야세 가쿠(Gaku HAYASE),최용화(Yonghwa CHOI),김영민(Youngmin KIM),최형서(Hyoungseo CHOI),길성호(Seongho KIL),윤백(Baek YOUN) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5
This paper reports a development of the Samsung electronics' new 9.52 ㎜ micro-fin tube for an air-conditioner and heat pumps. To optimize the micro-fin structure effect on the heat transfer characteristics and unit mass of the tube, empirical correlations are used and verified with experiments for a single-tube and a finned tube type heat exchanger. An experimental investigation of condensation heat transfer is conducted and R-22 is used as test refrigerant. The unit mass of the optimized micro-fin tube against the conventional tube is 12% lighter although wall thickness and strength of the burst pressure are the same degree. The evaporating heat transfer coefficient of the new 9.52 ㎜ micro-fin tube' is increased and the refrigerant pressure drop is decreased compare with the conventional tube. Also, the unit weight per length of the new tube is reduced.
박원걸(Wonkeol Park),김민지(Minji Kim),하야세 가쿠(Gaku Hayase),조금남(Keumnam Cho) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12
Frost forms on the surface of the heat exchanger as the heat pump operates below 0℃ under heating condition. Since frost blocks air flow through the heat exchanger, it increases air-side pressure drop and deteriorates heat transfer rate of the heat exchanger. Present study investigated frost characteristics and thermal performance of micro-channel heat exchanger using R-410A under frosting condition. Frost characteristics such as frost thickness, frost surface temperature etc were measured as well as transient heat transfer rate and pressure drop of the micro-channel heat exchanger under different frosting condition. Effect of non-uniformity of frost characteristics on the thermal performance of the frosted various micro-channel heat exchanger was investigated. Non-uniformity of frost growth caused decreasing of thermal performance of micro-channel heat exchanger.
히트펌프 조건시 휜-관 열교환기의 휜 부분의 착상에 관한 연구
윤신혁(Shinhyuk Yoon),조금남(Keumnam Cho),하야세 가쿠(Gaku Hayase) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11
The present study measured the frost thickness and frost mass on a flat plate to propose the correlation equations for the local and average frost thickness, frost density, and frost mass. Key parameters were the cooling surface temperature, absolute humidity of air, air temperature, and air velocity. A 50% ethylene glycol aqueous solution was applied as a coolant. The present study also measured the local frost thickness on a fin-tube model to compare the predicted values on the fin of the fin-tube model by the correlation equations from the experiments of the flat plate. The empirical correlations under the heat pump condition in the present study might predict more accurately than the other correlations. The proposed correlation for the frost thickness agreed with the measured data within 5%.
윤신혁(Shin-Hyuk Yoon),조금남(Keumnam Cho),하야세 가쿠(Gaku Hayase) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-
The present study measured the frost thickness and frost mass on a flat plate and on a circular tube to propose the correlation equations for the local and average frost thickness, frost density, and frost mass. Key parameters were the cooling surface temperature, absolute humidity of air, air temperature, and air velocity. A 50% ethylene glycol aqueous solution was applied as a coolant. The correlation equations for the frost thickness and mass of the flat plate and circular tube were proposed. They utilized topredict the frost thickness and mass of the simple fin and tube. The predicted local and average frost thicknesses and masses were compared with the measured values for the simple fin and tube. The local frost thickness on the fin decreased along the air flow direction. The predicted frost thickness agreed with the measured data within 5% while the predicted frost mass agreed with the measured data within 10%. The methodology to predict the frost for the simple fin and tube was developed and proposed.
윤신혁(Shin-Hyuk Yoon),조금남(Keumnam Cho),하야세 가쿠(Gaku Hayase) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-
The present study measured frost pattern on a cylinder to propose empirical correlation equations for the local and average frost thickness, frost density and frost mass. The key parameters were diameter of the cylinders (7㎜, 20㎜), cooling surface temperature of the circular tube, absolute humidity of air, air temperature and air velocity. A 50% ethylene glycol aqueous solution was applied as a coolant. The frost thicknesses at both front and rear were larger than those at the other parts, while they were increased as diameter of the cylinder was increased. The local frost thicknesses at high air velocity were more uniform than those at low air velocity. The values predicted by Kim et al. under the freezer condition showed larger by the maximum of 30~50% than the measured data under heat pump condition. The empirical correlations for the local and average frost thickness and frost mass were proposed. The correlation equations for the frost thickness and frost mass under the heat pump condition in the present study might predict more accurate than the other correlation equations. The proposed correlations might be applied for the freezer condition within the maximum 15% deviation from the previous correlations under freezer condition.
곽동근(Dongkwen Kwak),김승연(Seungyoun Kim),조금남(Keumnam Cho),하야세 가쿠(Gaku Hayase) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11
The present study investigated frost characteristics of fin-tube evaporator with multiple fins for the heat pump. Number of fin was ranged from one to five. Key test conditions were air temperature of 2℃, absolute humidity of air of 3.7g/㎏DA, air velocity of 0.5㎧, and surface temperature of the refrigerant of -10℃. The coolant was 50% ethylene-glycol aqueous solution. Local and average frost thicknesses were measured around the fin of the fin-tube. They were compared with the values predicted by the correlations obtained as the function of frost temperature for the flat plate and circular tube. Average frost mass was gradually increased as the number of fin increased even though frost characteristics for the case with multiple fin showed similar trend with the case with single fin through the test period. Similar frost pattern was observed at different gap between adjacent fins. The effect of number of fins on the frost characteristics was analyzed.
히트펌프 증발기의 착상 예측을 위한 핀-관 모델에서의 국부 서리 물성치와 서리성장에 관한 연구
곽동근(Dongkwen Kwak),이윤석(Yoonsuk Lee),조금남(Keumnam Cho),하야세 가쿠(Gaku Hayase) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5
The present study measured the frost characteristics on an array of fin-tube under the heat pump condition. The key parameters were air temperature from 2 to 7℃, absolute humidity of air from 2.98 to 3.92g/㎏DA, air velocity from 1 to 2m/s, and cooling surface temperature from -5 to -15℃. The coolant was 50% ethylene-glycol aqueous solution. Frost surface temperature was decreased and frost thickness was increased near the tube side of the fin-tube arrangement. Frost temperature profiles on the fin side were fully scanned. Heat transfer rate was increased up to 30 minutes and the decreased as the frost thickness was thickened as time passes.
윤신혁(Shin-Hyuk Yoon),조금남(Keumnam Cho),조홍기(Hong-Gi Cho),하야세 가쿠(Gaku Hayase) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5
The present study measured the frost thickness and frost mass on a flat plate to propose the correlation equations for the local and average frost thickness, frost density, and frost mass. Key parameters were the cooling surface temperature of the flat plate from 258.2 to 268.2 K, absolute humidity of air from 2.98 to 4.16 g/㎏<SUB>DA</SUB>, air temperature from 273.5 to 280.2 K, and air velocity from 1.0 to 2.5 ㎧. Although the area of the plate is the same, local frost thickness was changed along the direction of the flat plate. Correlation equations for the local and average frost thickness and frost mass under the heat pump condition were proposed. The predicted values by the correlation equations under the freezer condition showed larger by the maximum of 30~50% than the predicted values by the present correlation equations under the heat pump condition. The proposed correlation equations might be partly applied to the freezer condition.