Effect of periodic boundary conditions on heat transfer process of crude oil in floating roof storage tank

doi:10.11949/j.issn.0438-1157.20160361

Abstract

Abstract:

With the increase in demand for oil storage,the scale of tanks are developing towards the direction of large scale and better adaptability to extreme working conditions. The change of oil temperature field inside the tank should be accurately grasped, which is of great significance to guarantee safe and economical operation of oil depot. Aiming at the periodic change conditions of tank ambient conditions such as solar radiation, atmospheric temperature and etc., a theoretical model of the unsteady-state heat transfer process of large double-deck floating roof tank is established by using the theory of heat transfer, and the forward difference equations of boundary point are obtained by model region discretion. On basis of determining the physical properties of crude oil in the storage tank, heat transfer coefficient of the tank as well as the heat flux density of boundary, the numerical stimulation method of temperature field in the tank can be studied. The analysis and application of a 10×104 m³ floating roof storage tank in Daqing has shown that the temperature drop rate increases with the decrease of the solar radiation intensity and the atmospheric temperature. The effect of solar radiation on temperature drop rate of tank shell is small, which increases with the decrease of atmospheric temperature. The tank bottom is approximate to adiabatic state and the effect of the external environment on temperature drop rate is small. The results can provide theoretical support to optimize the storage process design and manufacturing management of large floating roof tanks.

Key words: periodic boundary, petroleum, heat transfer, numerical simulation

摘要：

随着石油储备需求的增加，油罐规模正向大型化以及能适应极限工况的方向发展。准确掌握罐内油品温度场的变化规律，对于保障油库安全经济运行具有重要意义。针对太阳辐射、大气温度等储罐环境的周期性变化条件，运用传热学相关理论，建立了大型双盘浮顶储罐非稳态传热过程的理论模型，通过对模型区域进行离散化得到边界节点的向前差分方程，在确定罐内原油物性参数、储罐传热系数以及边界热通量的基础上，研究得出储罐原油温度场的数值模拟方法。对大庆某10×10⁴ m³浮顶储罐的应用分析表明，罐顶温降速率随着太阳辐射强度以及大气温度的降低而增大；罐壁温降速率受太阳辐射影响较小，随大气温度的降低而增大；罐底近似于绝热，温降速率受外界环境影响较小，研究结果可为优化大型浮顶罐的储存工艺设计及生产管理提供一定的理论支持。

关键词: 周期性边界, 石油, 传热, 数值模拟

CLC Number:

TE821

SUN Wei, CHENG Qinglin, WANG Peidi, LI Yuchun, SUN Haiying. Effect of periodic boundary conditions on heat transfer process of crude oil in floating roof storage tank[J]. CIESC Journal, 2016, 67(9): 3640-3650.

孙巍, 成庆林, 王沛迪, 李玉春, 孙海英. 周期性边界条件对浮顶储罐原油传热过程的影响规律[J]. 化工学报, 2016, 67(9): 3640-3650.

References 21

[1]	孙梅, 赵映梅. 美日德石油储备筹资模式比较与借鉴[J]. 亚太经济, 2015, (4):90-95. SUN M, ZHAO Y M. Comparison and reference on the financing of petroleum reserves in United States, Japan and Germany[J]. China Academic Journal Electronic Publishing House, 2015, (4):90-95.
[2]	张晓涛, 孙梦然. 我国原油进口现状、问题及对策[J]. 经济纵横, 2011, (6):104-105. ZHANG X T, SUN M R. Current situation, problems and countermeasures of China's crude oil imports[J]. Economic Aspect, 2011, (6):104-105.
[3]	王红菊, 王晓梅, 石蕾. 浮顶油罐降温储存高凝原油[J]. 油气储运, 2007, 26(12):12-15. WANG H J, WANG X M, SHI L. High pour point crude oil is storaged by float roof tank cooling[J]. Oil & Gas Storage and Transportation, 2007, 26(12):12-15.
[4]	李超, 李旺, 刘人玮, 等. 大型油罐加热技术及温度场研究现状与展望[J]. 油气储运, 2013, 32(11):1161-1166. LI C, LI W, LIU R W, et al. Progress in the research of large-scale oil tank heating technology and temperature field[J]. Oil & Gas Storage and Transportation, 2013, 32(11):1161-1166.
[5]	王明吉, 张勇, 曹文. 原油储罐温降规律的实验研究[J]. 油气田地面工程, 2003, 22(11):58. WANG M J, ZHANG Y, CAO W. A study on temperature drop of a vertical floating roof crude oil tank[J]. Oil Field Surface Engineering, 2003, 22(11):58.
[6]	于达, 方徐应, 李东风, 等. 大型浮顶罐储油温降特点[J]. 油气储运, 2003, 22(9):47-49. YU D, FANG X Y, LI D F, et al. Temperature drop characteristic of oil in the large breathing roof tank[J]. Oil & Gas Storage and Transportation, 2003, 22(9):47-49.
[7]	REJANE D C O. Correlation for the cooling process of vertical storage tanks under natural convection for high Prandtl number[J]. International Journal of Heat and Mass Transfer, 2013, 57(1):292-298.
[8]	HUMPHREY C. Computational fluid dynamics study of flow around floating-roof oil storage tanks[J]. Journal of Wind Engineering and Industrial Aero Dynamics, 2000, 86(1):37-54.
[9]	侯磊, 白宇恒, 黄维秋. 浮顶罐内原油温降计算方法研究[J]. 科技通报, 2010, 26(1):159-164. HOU L, BAI Y H, HUANG W Q. Study on calculation method of temperature of crude oil in floating roof tank[J]. Bulletin of Science and Technology, 2010, 26(1):159-164.
[10]	RODRIGUEZ I, CASTRO J, PEREZ-SEGARRA C D, OLIVA A.Unsteady numerical simulation of the cooling process of vertical storage tanks under laminar natural convection[J]. International Journal of Thermal Sciences, 2009, 48:708-721.
[11]	成庆林, 孙巍, 邵帅, 等. 浮顶储油罐传热系数的变化规律及影响因素研究[J]. 节能技术, 2014, 32(2):151-154. CHENG Q L, SUN W, SHAO S, et al. The study of variation law and influence factors of heat transfer coefficient for floating roof storage tank[J]. Energy Conservation Technology, 2014, 32(2):151-154.
[12]	陆雅红, 吴江涛. 原油储罐盘管式蒸汽加热器优化设计[J]. 化学工程, 2010, 38(10):69-72. LU Y H, WU J T. Energy saving measures of crude oil storage tank[J]. Chemical Engineering (China), 2010, 38(10):69-72.
[13]	REJANE D C O, MARIO H M, JACQUELINE B C. Natural convection in a tank of oil:experimental validation of a numerical code with prescribed boundary condition[J]. Experimental Thermal and Fluid Science, 2005, (29):671-680.
[14]	OLIVESKI R D C, MACAGNAN M H. Natural convection in a tank of oil:experimental validation of a numerical code with prescribed boundary condition[J]. Experimental Thermal and Fluid Science, 2005, 29:671-680.
[15]	NURTEN V. Numerical analysis of the transient turbulent flow in a fuel oil storage tank[J]. International Journal of Heat and Mass Transfer, 2003; 46:3429-3440.
[16]	刘佳, 侯磊, 陈雪娇. 10×104 m3浮顶罐罐壁附近原油温度分布数值模拟[J]. 油气储运, 2015, 34(3):248-253. LIU J, HOU L, CHEN X J. Numerical simulation of crude oil temperature distribution near the tank wall of 10×104 m3 floating-roof tank[J]. Oil & Gas Storage and Transportation, 2015, 34(3):248-253.
[17]	郭光臣, 董文兰, 张志廉. 油库设计与管理[M]. 东营:石油大学出版社, 1991. GUO G C, DONG W L, ZHANG Z L. Design and Mnagement of Oil Depot[M]. Dongying:Petroleum University Publishing House, 1991.
[18]	李旺, 王情愿, 李瑞龙, 等. 大型浮顶油罐温度场数值模拟[J]. 化工学报, 2011, 62(S1):108-112. LI W, WANG Q Y, LI R L, et al. Numerical study on temperature field of a large floating roof oil tank[J]. CIESC Journal, 2011, 62(S1):108-112.
[19]	陶文铨. 数值传热学[M]. 西安:西安交通大学出版社, 2001. TAO W Q. Numerical Heat Transfer[M]. Xi'an:Xi'an Jiaotong University Press, 2001.
[20]	饶心, 伍奕, 林小飞, 等. 大型储罐单总线测温装置的研制[J]. 油气储运, 2010, 29(7):512-518. RAO X, WU Y, LIN X F, et al. Development of single bus temperature measurement device for large storage tank[J]. Oil & Gas Storage and Transportation, 2010, 29(7):512-518.
[21]	于达. 大型浮顶油罐测温系统的研发[J]. 油气储运, 2005, 24(8):41-43. YU D. Development on temperature monitoring system of large floating roof tank[J]. Oil & Gas Storage and Transportation, 2005, 24(8):41-43.