化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2015年
1期
426-432
,共7页
赵群志%章学来%刘田田%梁笑阳%罗孝学%丁磊
趙群誌%章學來%劉田田%樑笑暘%囉孝學%丁磊
조군지%장학래%류전전%량소양%라효학%정뢰
多孔介质%结晶%过冷度%相变%分布
多孔介質%結晶%過冷度%相變%分佈
다공개질%결정%과랭도%상변%분포
porous media%crystallization%degree of supercooling%phase change%distribution
影响水过冷度的因素很多,同样实验条件下水的过冷度并非一个定值,多孔球层的存在对水的过冷度产生一定影响。对蒸馏水和不同球径的多孔球层介质进行了32次过冷度测定实验,并对蒸馏水和多孔球层介质的蓄冷特性进行了实验研究。过冷度实验结果采用统计方法进行分析,并用 CCD 相机和热像仪对过冷现象进行观察。结果表明:大温差降温条件下水的平均过冷度要小于阶梯缓慢降温条件下水的过冷度;多孔球层球径越小,平均和峰值过冷度越小,但直径为11 mm出现特例,其平均过冷度比8 mm直径多孔球层要小,峰值也比8 mm的小;多孔球层固体基底的存在大大缩短了蓄冷相变时间。
影響水過冷度的因素很多,同樣實驗條件下水的過冷度併非一箇定值,多孔毬層的存在對水的過冷度產生一定影響。對蒸餾水和不同毬徑的多孔毬層介質進行瞭32次過冷度測定實驗,併對蒸餾水和多孔毬層介質的蓄冷特性進行瞭實驗研究。過冷度實驗結果採用統計方法進行分析,併用 CCD 相機和熱像儀對過冷現象進行觀察。結果錶明:大溫差降溫條件下水的平均過冷度要小于階梯緩慢降溫條件下水的過冷度;多孔毬層毬徑越小,平均和峰值過冷度越小,但直徑為11 mm齣現特例,其平均過冷度比8 mm直徑多孔毬層要小,峰值也比8 mm的小;多孔毬層固體基底的存在大大縮短瞭蓄冷相變時間。
영향수과랭도적인소흔다,동양실험조건하수적과랭도병비일개정치,다공구층적존재대수적과랭도산생일정영향。대증류수화불동구경적다공구층개질진행료32차과랭도측정실험,병대증류수화다공구층개질적축랭특성진행료실험연구。과랭도실험결과채용통계방법진행분석,병용 CCD 상궤화열상의대과랭현상진행관찰。결과표명:대온차강온조건하수적평균과랭도요소우계제완만강온조건하수적과랭도;다공구층구경월소,평균화봉치과랭도월소,단직경위11 mm출현특례,기평균과랭도비8 mm직경다공구층요소,봉치야비8 mm적소;다공구층고체기저적존재대대축단료축랭상변시간。
There are many factors which affect supercooling of water. Under the same experimental conditions, supercooling degree of water is not a fixed value. The presence of bead-packed porous structure influences the supercooling of water. Experiments to test supercooling of distilled water and different ball diameters of bead-packed porous structure were conducted thirty two times. And experiments about characteristics of cold storage of distilled water and different ball diameters of bead-packed porous structure were also conducted. Experimental results of supercooling were analyzed using statistical methods, and a CCD camera and a thermal imager were used for observing the phenomenon of supercooling. The average supercooling degree of distilled water under the condition of cooling with large temperature difference was lower than that under the condition of stepped slow cooling. The smaller the ball diameter in bead-packed porous structure, the smaller the average and peak supercooling degree, but there was a special circumstance when ball diameter was 11 mm. The average supercooling degree and the peak value of bead-packed porous structure with 11 mm ball diameter were smaller than that with 8 mm ball diameter. In addition, the presence of a porous solid base greatly reduced storage phase transition time.