摘要
采用数值模拟的方法分析了内置圆形发热体位置对二维方腔内自然对流的影响.结果表明:相同Ra下,发热体越靠近底部,方腔内自然对流越强,发热体表面Nu也逐渐增大;在低Ra下,发热体位于方腔左右两侧时的Nu大于中间位置的Nu,随着Ra的升高,发热体在方腔中间位置的Nu逐渐高于在左右两侧位置的Nu;Ra=104时,底部左右两侧位置的Nu比底部中间位置的Nu大8.78%,而Ra=106时,底部中间位置的Nu比底部左右两侧位置的Nu大8.44%;Ra=106时,发热体位于方腔底部中间位置和上部两侧位置时,Nu分别达到最大值和最小值,最大值比最小值高18.63%.
The impact of the positions of a build-in hot circular cylinder on the natural convection in a twodimensional square enclosure was analyzed through numerical simulation.The results show that,under the same value of Ra,the closer the cylinder is to the bottom,the stronger the natural convection in the square enclosure,and the larger the value of Nuon the surface of the cylinder.Under low value of Ra,the value of Nuof the hot cylinder when the position of the cylinder is near the left and right sides of the enclosure is larger than that when the cylinder is located at the middle of the enclosure.Then with the increase of the value of Ra,the value of Nuwhen the hot cylinder is located at the middle of the enclosure gradually increases to a degree larger than that with hot cylinder located at left and right sides of the enclosure.At Ra=104,the value of Nu with hot cylinder located at lower left or right sides of the enclosure is 8.78%larger than the value of Nu with the hot cylinder located at the lower middle of the enclosure,while the value of Nu with the hot cylinder located at the lower middle of the enclosure is 8.44% higher than the corresponding value of Nu with the hot cylinder located at the left or right sides of the enclosure at Ra=106.The value of Nureaches the maximum when the hot cylinder is located at the bottom centre of the enclosure and minimum when it is located at the two sides of the upper position respectively at Ra=106,and the corresponding maximum vulue of Nuis 18.63%larger than the minimum value.
作者
陈中豪
罗超
吴帅
宋克伟
CHEN Zhong hao;LUO Chao;WU Shuai;SONG Ke wei(Key Laboratory of Railway Vehicle Thermal Engineering,Ministry of Education,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《兰州交通大学学报》
CAS
2018年第4期78-84,共7页
Journal of Lanzhou Jiaotong University
基金
甘肃省自然科学基金(17JR5RA092)
甘肃省高等学校创新团队项目(2018C-13)
关键词
封闭方腔
内置圆形发热体
自然对流
数值模拟
square enclosure
build in hot circular cylinder
natural convection
numerical simulation
