双层多孔介质燃烧反应器的孔隙尺度计算流体动力学模拟

doi:10.16085/j.issn.1000-6613.2025-0114

摘要/Abstract

摘要：

双层多孔介质燃烧反应器具有燃烧效率高、燃料燃烧极限宽、污染物排放少等优点，在工业应用中具有重要应用价值，然而其内部流动-传递-反应过程复杂，难以实现双层多孔介质反应器的精准调控与优化。为此，本文基于孔隙尺度的计算流体动力学（computational fluid dynamics，CFD）方法，采用搭桥的方法模拟固体间的热传导，对双层多孔介质甲烷燃烧器进行了二维全尺寸数值模拟，研究了特定当量比下不同入口速度以及特定入口速度不同当量比对燃烧行为的影响。计算结果表明，火焰分散在孔隙中，稳定在燃烧器某一水平位置，当入口气体速度较低时（0.3m/s），火焰驻定在双层多孔介质的交界面附近，火焰位置随流速的增大向下游移动，随当量比的增大向上游移动，火焰温度随入口速度的增加而增加，温度分布局部化，局部高温出现在较小的孔隙间。燃烧在孔隙内更加剧烈，最大速度可达到入口速度的56.0~58.7倍。因此，双层多孔介质燃烧反应器的孔隙尺度CFD模拟可以揭示其内部的流动-传递-反应特性。

关键词: 多孔介质, 计算流体力学, 数值模拟, 孔隙尺度, 反应器

Abstract:

The double-layer porous media combustor offers advantages of high combustion efficiency, a wide fuel combustion limit, and low pollutant emissions, making it valuable for industrial applications. However, the complex flow-transfer-reaction behaviors inside the reactor leads to challenges of design, control, and optimization. In this work, the pore scale computational fluid dynamics (CFD) was employed to modelling a full-scale double-layer porous media methane combustor. A bridge method was utilized to simulate solid-particle heat conduction, where a porous zone connects with adjacent particles. The effects of various inlet velocities and equivalence ratios on methane combustion behaviors were investigated. The results showed that the flame was dispersed within the pores and stabilized at a certain horizontal position in the combustor. Specifically, the flame was stabilized near the interface of the two porous media layers at low flow velocity (0.3m/s). With the increase of inlet velocity, the flame position is shifted downstream. Conversely, The flame position was shifted to upstream with an increase of equivalence ratio. The flame temperature increased with an increasing of inlet velocity, resulting in a localized temperature distribution, which a high temperatures zone existed in the smaller pore regions. Additionally, the maximum velocities were found to reach 56.0—58.7 times of the inlet velocity. The results also showed that pore scale CFD simulation could reveal the flow-transfer-reaction behaviors of double-layer porous medium combustion reactors.

Key words: porous media, computational fluid dynamics (CFD), numerical simulation, pore scale, reactors

中图分类号:

TQ51

李卡, 夏宇轩, 吴晓琴, 易兰, 罗浩. 双层多孔介质燃烧反应器的孔隙尺度计算流体动力学模拟[J]. 化工进展, 2025, 44(8): 4381-4393.

LI Ka, XIA Yuxuan, WU Xiaoqin, YI Lan, LUO Hao. Pore scale computational fluid dynamics (CFD) simulation of a double-layer porous medium combustion reactor[J]. Chemical Industry and Engineering Progress, 2025, 44(8): 4381-4393.

图/表 18

图1 简化后的燃烧器多孔介质几何模型

表1 氧化铝与高岭棉物性参数

物性参数	氧化铝	高岭棉
密度/kg·m^-3	3987	128
发射率	0.75	0.75
吸收系数/m^-1	3.7	0
散射系数/m^-1	50.88	0

表2 氧化铝比热容和热导率

温度/K	比热容/kJ·kg^-1·K^-1	热导率/W·m^-1·K^-1
293	0.755	33
773	1.165	11.4
1273	1.255	7.22
1473	1.285	6.67
1673	1.315	6.34
1773	1.330	6.23

表3 高岭棉比热容和热导率

温度/K	比热容/kJ·kg^-1·K^-1	热导率/W·m^-1·K^-1
533	0.871	0.06
811	0.871	0.12
1089	0.871	0.21
1366	0.871	0.3

表4 不同区域的控制方程

区域	连续性方程	动量方程	能量方程	组分输运方程
非多孔介质流体区域	$∇ ⋅ ρ g u = 0$	$∇ ⋅ ρ g u u = - ∇ p + ∇ ⋅ τ + ρ g g$	$∇ ⋅ ρ g u h + u 2 2 = ∑ i ω i h i M i - ∇ ⋅ q r + ∇ ⋅ k e f f ∇ T g - ∑ i h i J i + τ ⋅ u$	$∇ ⋅ ρ g u Y i = - ∇ ⋅ J i + R i$
多孔介质区域	$∇ ⋅ ε ρ g u = 0$	$∇ ⋅ ε ρ g u u = - ε ∇ p + ∇ ⋅ ε τ + ε ρ g g - μ K u + C 2 2 ρ g u u$	$∇ ⋅ ε ρ g u h + u 2 2 = ε ∑ i ω i h i M i - ∇ ⋅ ε q r + ∇ ⋅ k e f f, s ∇ T g - ε ∑ i h i J i + ε τ ⋅ u$	$∇ ⋅ ε ρ g u Y i = - ∇ ⋅ ε J i + ε R i$
固体区域	—	—	$∇ ⋅ k s ∇ T s + Q r a d, s = 0$	—

表4 不同区域的控制方程

区域	连续性方程	动量方程	能量方程	组分输运方程
非多孔介质流体区域	$∇ ⋅ ρ g u = 0$	$∇ ⋅ ρ g u u = - ∇ p + ∇ ⋅ τ + ρ g g$	$∇ ⋅ ρ g u h + u 2 2 = ∑ i ω i h i M i - ∇ ⋅ q r + ∇ ⋅ k e f f ∇ T g - ∑ i h i J i + τ ⋅ u$	$∇ ⋅ ρ g u Y i = - ∇ ⋅ J i + R i$
多孔介质区域	$∇ ⋅ ε ρ g u = 0$	$∇ ⋅ ε ρ g u u = - ε ∇ p + ∇ ⋅ ε τ + ε ρ g g - μ K u + C 2 2 ρ g u u$	$∇ ⋅ ε ρ g u h + u 2 2 = ε ∑ i ω i h i M i - ∇ ⋅ ε q r + ∇ ⋅ k e f f, s ∇ T g - ε ∑ i h i J i + ε τ ⋅ u$	$∇ ⋅ ε ρ g u Y i = - ∇ ⋅ ε J i + ε R i$
固体区域	—	—	$∇ ⋅ k s ∇ T s + Q r a d, s = 0$	—

表5 反应动力学参数

编号	反应	指前因子	活化能/J·kmol^-1	反应级数
S1	$C H 4 + 1.5 O 2 → C O + 2 H 2 O$	5.012×10¹¹	2×10⁸	[CH₄]^0.7[O₂]^0.8
S2	$C O + 0.5 O 2 → C O 2$	2.239×10¹²	1.7×10⁸	[CO][O₂]^0.5
S3	$C O 2 → 0.5 O 2 + C O$	5×10⁸	1.7×10⁸	[CO₂]

表5 反应动力学参数

编号	反应	指前因子	活化能/J·kmol^-1	反应级数
S1	$C H 4 + 1.5 O 2 → C O + 2 H 2 O$	5.012×10¹¹	2×10⁸	[CH₄]^0.7[O₂]^0.8
S2	$C O + 0.5 O 2 → C O 2$	2.239×10¹²	1.7×10⁸	[CO][O₂]^0.5
S3	$C O 2 → 0.5 O 2 + C O$	5×10⁸	1.7×10⁸	[CO₂]

表6 燃烧器入口质量分数

CH₄	N₂	O₂	CO₂
0.0369	0.7361	0.2264	0.0006

表7 多孔介质阻力系数

阻力系数	3mm颗粒		6mm颗粒
阻力系数	黏性阻力/m^-2	惯性阻力/m^-1	黏性阻力/m^-2	惯性阻力/m^-1
1	3.745×10⁷	10937.5	7.322×10⁶	4182
1/8	4681250	1367.2	915250	522.75
1/32	1170312.5	341.8	228812.5	130.6875
1/128	292578.12	82.45	57203.12	32.67

图2 不同入口速度时各阻力系数计算温度与实验温度对比

图3 不同入口气体速度时双层多孔介质甲烷燃烧器内中心轴线上的实验温度与模拟温度对比（当量比为0.65）

图4 不同入口气体速度时双层多孔介质甲烷燃烧器内部的流体温度分布（当量比为0.65）

图5 最高温度、表面温度与入口速度的关系

图6 不同入口气体速度时双层多孔介质甲烷燃烧器内的固体颗粒温度分布（当量比为0.65）

图7 不同入口气体速度时双层多孔介质甲烷燃烧器内的流体速度分布（当量比为0.65）

图8 不同入口气体速度时双层多孔介质甲烷燃烧器CFD模拟的甲烷、氧气、二氧化碳、水的质量分数云图（当量比为0.65）

图9 不同当量比时双层多孔介质甲烷燃烧器流体温度分布（入口速度为0.3m/s）

图10 不同当量比时双层多孔介质甲烷燃烧器内的固体颗粒温度分布（入口速度为0.3m/s）

图11 不同当量比时双层多孔介质甲烷燃烧器CFD模拟的流体速度分布（入口速度为0.3m/s）

参考文献 27

[1]	缪雪龙, 黄震. 内燃机燃烧技术综述[J]. 现代车用动力, 2006(2): 6-11, 27.
	MIAO Xuelong, HUANG Zhen. Review of combustion technology in internal combustion engine[J]. Modern Vehicle Power, 2006(2): 6-11, 27.
[2]	李苏辉, 张归华, 吴玉新. 面向未来燃气轮机的先进燃烧技术综述[J]. 清华大学学报(自然科学版), 2021, 61(12): 1423-1437.
	LI Suhui, ZHANG Guihua, WU Yuxin. Advanced combustion technologies for future gas turbines[J]. Journal of Tsinghua University (Science and Technology), 2021, 61(12): 1423-1437.
[3]	凌忠钱, 周昊, 孔俊俊. 多孔介质燃烧波传播中的“超焓” 特性[J]. 浙江大学学报(工学版), 2014, 48(4): 660-665.
	LING Zhongqian, ZHOU Hao, KONG Junjun. Super-adiabatic characteristic of porous media combustion at different wave propagation direction[J]. Journal of Zhejiang University (Engineering Science), 2014, 48(4): 660-665.
[4]	汪健生, 张辉鹏, 刘雪玲, 等. 多孔介质结构对储层内流动和换热特性的影响[J]. 化工进展, 2023, 42(8): 4212-4220.
	WANG Jiansheng, ZHANG Huipeng, LIU Xueling, et al. Analysis of flow and heat transfer characteristics in porous media reservoir[J]. Chemical Industry and Engineering Progress, 2023, 42(8): 4212-4220.
[5]	Abdul MUJEEBU M, ABDULLAH M Z, BAKAR M Z ABU, et al. Applications of porous media combustion technology—A review[J]. Applied Energy, 2009, 86(9): 1365-1375.
[6]	WOOD Susie, HARRIS Andrew T. Porous burners for lean-burn applications[J]. Progress in Energy and Combustion Science, 2008, 34(5): 667-684.
[7]	黄冉思思, 程乐鸣, 邱坤赞, 等. 中、低热值预混气体在双层多孔介质中的贫燃特性[J]. 浙江大学学报(工学版), 2015, 49(9): 1783-1789.
	HUANG Ransisi, CHENG Leming, QIU Kunzan, et al. Lean combustion of moderate/low calorific premixed gases in two-layer porous burner[J]. Journal of Zhejiang University (Engineering Science), 2015, 49(9): 1783-1789.
[8]	BUBNOVICH V, HENRÍQUEZ L, GNESDILOV N. Numerical study of the effect of the diameter of alumina balls on flame stabilization in a porous-medium burner[J]. Numerical Heat Transfer, Part A: Applications, 2007, 52(3): 275-295.
[9]	LIANG Xiong, LI Yawei, HE Zhu, et al. Design of three-layered struts in SiC reticulated porous ceramics for porous burner[J]. Ceramics International, 2019, 45(7): 8571-8576.
[10]	SAMOILENKO Mykhailo, SEERS Patrice, TERRIAULT Patrick, et al. Design, manufacture and testing of porous materials with ordered and random porosity: Application to porous medium burners[J]. Applied Thermal Engineering, 2019, 158: 113724.
[11]	WANG Guanqing, TANG Pengbo, LI Yuan, et al. Flame front stability of low calorific fuel gas combustion with preheated air in a porous burner[J]. Energy, 2019, 170: 1279-1288.
[12]	LIU Yang, DENG Yangbo, SHI Junrui, et al. Experimental investigation on flame stability and emissions of lean premixed methane-air combustion in a developed divergent porous burner[J]. Journal of Cleaner Production, 2023, 405: 137070.
[13]	李宁, 李金科, 董金善. 乙烯裂解炉多孔介质燃烧器的研究与开发[J]. 化工进展, 2023, 42(S1): 73-83.
	LI Ning, LI Jinke, DONG Jinshan. Research and development of porous medium burner in ethylene cracking furnace[J]. Chemical Industry and Engineering Progress, 2023, 42(S1): 73-83.
[14]	SHI Junrui, CHEN Zhongshan, LI Houping, et al. Pore-scale study of thermal nonequilibrium in a two-layer burner formed by staggered arrangement of particles[J]. Applied Thermal Engineering, 2020, 176: 115376.
[15]	SHI Junrui, Jinsheng LYU, HE Fang, et al. 3D numerical study on syngas production in a structured packed bed with connected pellets[J]. International Journal of Hydrogen Energy, 2020, 45(56): 32579-32588.
[16]	Jinsheng LYU, SHI Junrui, MAO Mingming, et al. Three-dimensional pore-scale simulation of flow and thermal non-equilibrium for premixed gas combustion in a random packed bed burner[J]. Energies, 2021, 14(21): 6939.
[17]	LI Qingqing, LI Jun, SHI Junrui. Fully-resolved 3D premixed H₂/air flames in a micro-combustor partially filled with porous media: Effects of detailed pore structures[J]. Proceedings of the Combustion Institute, 2023, 39(4): 5571-5580.
[18]	LIU Yang, DENG Yangbo, SHI Junrui, et al. Pore-level numerical simulation of methane-air combustion in a simplified two-layer porous burner[J]. Chinese Journal of Chemical Engineering, 2021, 34: 87-96.
[19]	GAO Huaibin, QU Zhiguo, HE Yaling, et al. Experimental study of combustion in a double-layer burner packed with alumina pellets of different diameters[J]. Applied Energy, 2012, 100: 295-302.
[20]	SHI Junrui, MAO Mingming, LI Houping, et al. A pore level study of syngas production in two-layer burner formed by staggered arrangement of particles[J]. International Journal of Hydrogen Energy, 2020, 45(3): 2331-2340.
[21]	SHI Junrui, KONG Xiangjin, Jinsheng LYU, et al. The stability limit of extremely low calorific gas combustion in a cone-shape two-section burner with the preheaters[J]. International Communications in Heat and Mass Transfer, 2023, 140: 106524.
[22]	Morgan Thermal Ceramics. Kaowool^® Blanket: Datasheet Code US 5-14-205[J/OL]. Morgan Advanced Materials, (2018-07) [2024-12-06]. .
[23]	DIXON Anthony G, NIJEMEISLAND Michiel, STITT E Hugh. Systematic mesh development for 3D CFD simulation of fixed beds: Contact points study[J]. Computers & Chemical Engineering, 2013, 48: 135-153.
[24]	ZEIDAN D, BÄHR P, FARBER P, et al. Numerical investigation of a mixture two-phase flow model in two-dimensional space[J]. Computers & Fluids, 2019, 181: 90-106.
[25]	MENTER F R. Two-equation eddy-viscosity turbulence models for engineering applications[J]. AIAA Journal, 1994, 32(8): 1598-1605.
[26]	HEADLEY Alexander J, HILEMAN Michael B, ROBBINS Aron S, et al. Thermal conductivity measurements and modeling of ceramic fiber insulation materials[J]. International Journal of Heat and Mass Transfer, 2019, 129: 1287-1294.
[27]	ERGUN Sabri, ORNING A A. Fluid flow through randomly packed columns and fluidized beds[J]. Industrial & Engineering Chemistry, 1949, 41(6): 1179-1184.