摘要
以填充石蜡的矩形腔(分为无翅片矩形腔、带翅片矩形腔)为研究对象,建立数学模型。采用有限元软件COMSOL Multiphysics模拟矩形腔内石蜡的熔化行为,分析不同翅片排布方式对石蜡熔化行为的影响,筛选有利于增强石蜡熔化的翅片排布方式。矩形腔右侧壁面为受热面,其他3个面为绝热面,带翅片矩形腔的翅片设置在受热面内侧。在翅片数量(3个翅片)、间隔不变的前提下,保持矩形腔内翅片总长度不变,设置4种翅片排布方式。排布方式1:每个翅片长度均为32 mm。排布方式2:自下而上的翅片长度分别为41、32、23 mm。排布方式3:自下而上的翅片长度分别为23、32、41 mm。排布方式4:自下而上的翅片长度分别为29、38、29 mm。对于无翅片矩形腔,在自然对流传热作用下,右上角的石蜡最先熔化,然后熔化部分向矩形腔中心扩散,直至矩形腔左下角石蜡完全熔化。矩形腔增加翅片可有效改善石蜡熔化的均匀性,缩短了矩形腔内石蜡的熔化时间。排布方式2对改善矩形腔内石蜡熔化均匀性的效果最理想,石蜡完全熔化的时间最短。相同受热时间下,带翅片矩形腔内石蜡的液相面积比(液相石蜡面积与矩形面积之比)明显高于无翅片矩形腔。无翅片矩形腔内石蜡完全熔化的受热时间为3 522 s,带翅片矩形腔翅片排布方式1~4的石蜡完全熔化的受热时间分别为1 874、1 674、2 082、1 910 s。将等长翅片的排布方式1作为基准,评价其他3种翅片排布方式对矩形腔内石蜡熔化的增强作用。翅片排布方式2对矩形腔内石蜡熔化的增强作用明显,增强作用集中在熔化过程的中后期。排布方式3、4起到了相反作用。
The rectangular cavity filled with paraffin( divided into a rectangular cavity without fins and a rectangular cavity with fins) was used as the research object to establish a mathematical model. The finite element software COMSOL Multiphysics was used to simulate the melting behavior of paraffin in the rectangular cavity,and the influence of different fin arrangements on the melting behavior of paraffin was analyzed,so as to screen the fin arrangement that help enhance the paraffin melting. The right wall of the rectangular cavity is the heating surface,and the other three walls are adiabatic surfaces. The fins of the rectangular cavity with fins are arranged inside the heating surface. On the premise that the number of fins( 3 fins) and the same interval,the total length of fins in the rectangular cavity remains unchanged,and four fin arrangement modes are set. Arrangement mode 1: The length of each fin is 32 mm. Arrangement 2 mode: The lengths of the bottom-up fins are 41,32 and 23 mm,respectively. Arrangement 3 mode: The lengths of the bottom-up fins are 23,32 and 41 mm,respectively. Arrangement 4 mode: The lengths of the bottom-up fins are 29,38 and 29 mm,respectively. For the rectangular cavity without fins,under the action of natural convection heat transfer,the paraffin in the upper right corner melts first,then the melted part diffuses to the center of the rectangular cavity until the paraffin in the lower left corner of the rectangular cavity completely melts. Adding fins in rectangular cavity can improve the melting uniformity of paraffin and shorten the melting time of paraffin in rectangular cavity. The arrangement mode 2 has the best effect on improving the melting uniformity of paraffin in the rectangular cavity,and the time of complete melting of paraffin is the shortest.Under the same heating time,the liquid phase area ratio( ratio of liquid phase paraffin area to rectangle area)of paraffin in the rectangular cavity with fins is significantly higher than that in the rectangular cavity without fins
作者
程素雅
陈宝明
郭梦雪
张艳勇
李佳阳
CHENG Suya;CHEN Baoming;GUO Mengxue;ZHANG Yanyong;LI Jiayang
出处
《煤气与热力》
2020年第4期7-12,15,J0041,J0042,共9页
Gas & Heat
基金
国家自然科学基金面上项目(51976111)。
关键词
矩形腔
石蜡相变蓄热
等长翅片
非等长翅片
熔化
rectangular cavity
paraffin phase change heat storage
equal-length fin
non-equal fin
melting
