化工学报
化工學報
화공학보
CIESC Jorunal
2015年
11期
4394-4400
,共7页
纳米粒子%传热%测量%传热系数%预测%关联式
納米粒子%傳熱%測量%傳熱繫數%預測%關聯式
납미입자%전열%측량%전열계수%예측%관련식
nanoparticles%heat transfer%measurement%heat transfer coefficient%prediction%correlation
搭建了纳米冷冻机油/制冷剂水平光管内流动沸腾换热测试实验台，研究了石墨/R600a纳米制冷剂在水平直光管内流动沸腾换热特性，分析了纳米石墨对含油制冷剂流动沸腾换热的影响。实验测试段为总长2.5 m、外径9.52 mm、内径8 mm、壁厚0.76 mm的紫铜管。在质量流速为150、200、250、300 kg·m?2·s?1下，分别测量纯R600a、含油R600a、不同质量分数（0.05%、0.1%、0.2%）纳米石墨冷冻机油和R600a混合物在水平光滑圆管内流动沸腾传热系数随干度的变化趋势。实验结果表明：纳米石墨的添加增强了含油制冷剂的流动沸腾换热。实验获得了基于石墨的含油纳米制冷剂流动沸腾换热关联式，关联式的预测值与94.5%的实验数据偏差在±15%以内。
搭建瞭納米冷凍機油/製冷劑水平光管內流動沸騰換熱測試實驗檯，研究瞭石墨/R600a納米製冷劑在水平直光管內流動沸騰換熱特性，分析瞭納米石墨對含油製冷劑流動沸騰換熱的影響。實驗測試段為總長2.5 m、外徑9.52 mm、內徑8 mm、壁厚0.76 mm的紫銅管。在質量流速為150、200、250、300 kg·m?2·s?1下，分彆測量純R600a、含油R600a、不同質量分數（0.05%、0.1%、0.2%）納米石墨冷凍機油和R600a混閤物在水平光滑圓管內流動沸騰傳熱繫數隨榦度的變化趨勢。實驗結果錶明：納米石墨的添加增彊瞭含油製冷劑的流動沸騰換熱。實驗穫得瞭基于石墨的含油納米製冷劑流動沸騰換熱關聯式，關聯式的預測值與94.5%的實驗數據偏差在±15%以內。
탑건료납미냉동궤유/제랭제수평광관내류동비등환열측시실험태，연구료석묵/R600a납미제랭제재수평직광관내류동비등환열특성，분석료납미석묵대함유제랭제류동비등환열적영향。실험측시단위총장2.5 m、외경9.52 mm、내경8 mm、벽후0.76 mm적자동관。재질량류속위150、200、250、300 kg·m?2·s?1하，분별측량순R600a、함유R600a、불동질량분수（0.05%、0.1%、0.2%）납미석묵냉동궤유화R600a혼합물재수평광활원관내류동비등전열계수수간도적변화추세。실험결과표명：납미석묵적첨가증강료함유제랭제적류동비등환열。실험획득료기우석묵적함유납미제랭제류동비등환열관련식，관련식적예측치여94.5%적실험수거편차재±15%이내。
A test rig with a horizontal smooth tube was built to measure flow boiling heat transfer of nanolubricant/refrigerant. The experimental study on heat transfer characteristics of graphite-nanorefrigerant flow boiling inside a horizontal smooth copper tube, with total length of 2.5 m, outside diameter of 9.52 mm, inside diameter of 8 mm and wall thickness of 0.76 mm was performed. Influence of graphite on flow boiling heat transfer characteristics of nanorefrigerant/oil mixture was investigated. There were three kinds of fluid under experiment:R600a, R600a/oil and graphite nanorefrigerant/oil with different graphite mass fractions (0.05%, 0.1% and 0.2%). Flow boiling heat transfer coefficients of these fluidversus vapor quality were measured respectively in a horizontal smooth tube under the mass flow density of 150, 200, 250, 300 kg·m?2·s?1. The results indicated that the presence of graphite enhanced the flow boiling heat transfer. A correlation for predicting the flow boiling heat transfer coefficient of nanorefrigerant/oil mixture with graphite was proposed and it agreed with 94.5% of the experimental data within a deviation of±15%.
