Mg-O_2和Mg-CO_2预混气燃烧特性及热声振荡的数值模拟研究
|
摘要
基于金属镁在高超声速飞行器及火星探测器上的应用,为探讨金属燃料在不同氧化剂环境中的燃烧特性及热声不稳定性机理,开展了数值模拟研究。考虑镁蒸气与O_2和CO_2两种氧化剂的剧烈反应区,构建了预混燃烧的二维燃烧室模型,详细探讨了预混气当量比、预混气初温及入口速度等对燃烧特性及热声振荡特性的影响规律,并与CHEMKIN计算结果进行了比较分析。结果表明,较高的当量比下燃烧室的燃烧速率更快,燃烧平衡温度更高,此外增加预混气初温能加快燃烧室燃烧速率,而更高的入口速度会使燃烧室的压力振荡从低频高振幅振荡向高频低振幅振荡转化。燃烧室的压力振荡同时存在轴向振荡和径向振荡,振荡曲线为高频振荡和低频振荡的不同组合。入口速度对燃烧室压力振荡有较大影响,入口速度越快,振荡频率越高,而声压级越低。此外,预混气当量比和预混气初温对燃烧室的压力振荡也有一定影响。
Based on the application of magnesium fuel in hypersonic vehicle and Mars explorer,the combustion characteristics of magnesium vapor in O_2 and CO_2 environment were investigated. In numerical simulation,the reaction mechanism for Mg-O_2 and Mg-CO_2 were considered,the flow field distribution and thermoacoustic oscillation in combustion chamber were studied based on a 2D model,and the results were compared with the calculation results in CHEMKIN. Simulation results show that: Equivalent ratio,initial temperature and inlet velocity affect the combustion characteristics in combustor,the fuel rich premixture has a better combustion performance than the lean premixture. The burning rate is accelerated with the increase of the initial temperature of the premixed gas,and higher inlet velocity will change the pressure oscillation in combustor from low frequency and high amplitude oscillation to high frequency and low amplitude oscillation. Besides,the pressure oscillation mode in combustor is a combination of axial oscillation and radial oscillation. The higher the inlet velocity is,the higher the oscillation frequency is,but the sound pressure level is lower. Besides,the pressure oscillation is also influenced by equivalence ratio and initial temperature.
Based on the application of magnesium fuel in hypersonic vehicle and Mars explorer,the combustion characteristics of magnesium vapor in O_2 and CO_2 environment were investigated. In numerical simulation,the reaction mechanism for Mg-O_2 and Mg-CO_2 were considered,the flow field distribution and thermoacoustic oscillation in combustion chamber were studied based on a 2D model,and the results were compared with the calculation results in CHEMKIN. Simulation results show that: Equivalent ratio,initial temperature and inlet velocity affect the combustion characteristics in combustor,the fuel rich premixture has a better combustion performance than the lean premixture. The burning rate is accelerated with the increase of the initial temperature of the premixed gas,and higher inlet velocity will change the pressure oscillation in combustor from low frequency and high amplitude oscillation to high frequency and low amplitude oscillation. Besides,the pressure oscillation mode in combustor is a combination of axial oscillation and radial oscillation. The higher the inlet velocity is,the higher the oscillation frequency is,but the sound pressure level is lower. Besides,the pressure oscillation is also influenced by equivalence ratio and initial temperature.
引文
[1] Cassel H M,Liebman I. The Cooperative Mechanism in the Ignition of Dust Dispersions[J]. Combustion and Flame,1959,3(59):467-475.
[2] Boiko V M,Lotov V V,Papyrin A N. Ignition of Gas Suspensions of Metallic Powders in Reflected Shock Waves[J]. Combustion Explosion and Shock Waves,1989,25(2):193-199.
[3] Wickman J. In-situ Mars Rocket and Jet Engines Burning Carbon Dioxide[C]. Los Angeles:35th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit,1999.
[4] Linnell J,Miller T. A Preliminary Design of a Magnesium Fueled Martian Ramjet Engine[C]. Indianapolis:38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit,2002.
[5] Glassman I. Metal Combustion Processes[J]. American Rocket Society,1959,6(2):311-23.
[6] Liang Y,Beckstead M. Numerical Simulation of QuasiSteady,Single Aluminum Particle Combustion in Air[C]. Reno:The 36th AIAA Aerospace Sciences Meeting and Exhibit,1998.
[7]林长津,王浩,朱晨光,等.镁金属微粒非快速燃烧反应模型及数值分析[J].含能材料,2015,23(6):573-577.
[8]潘宏亮,李逢春,王克秀.镁粉粒度对点火延迟影响的实验和理论研究[J].推进技术,1987,8(3).(PANG Hong-liang,LI Feng-chun,WANG Ke-xiu.Experimental and Theoretical Research about the Effects of Magnesium Powder Particle Size on Ignition Delay[J].Journal of Propulsion Technology,1987,8(3).)
[9] Abbud-Madrid A,Branch M,Daily J. On the Burning Behavior of Radiatively-Ignited Bulk Titanium and Magnesium in Low Gravity[C]. Reno:The 34th Aerospace Sciences Meeting and Exhibit,1996.
[10] Dreyer C B. Planar Laser Induced Fluorescence Measurements of Magnesium Oxide During Combustion of Magnesium with Oxygen and Carbon Dioxide[C]. Reno:The 39th Aerospace Sciences Meeting and Exhibit,2001.
[11] Goroshin S,Higgins A,Kamel M. Powdered Metals as Fuel for Hypersonic Ramjets[R]. AIAA 2001-3919.
[12]申慧君,夏智勋,胡建新,等.金属粉末燃料冲压发动机初步试验研究[J].固体火箭技术,2008,31(3):225-227.
[13]申慧君,夏智勋,胡建新,等.粉末燃料冲压发动机自维持稳定燃烧试验研究[J].固体火箭技术,2009,32(2):145-149.
[14] Lieuwen T C,Vigor Yang. Combustion Instabilities in Gas Turbine Engines[M]. Texas:American Institute of Astronautics,2005.
[15]杨亚晶,李晓亚,荆宏达.镁基燃料水冲压发动机的热声振荡特性研究[J].推进技术,2016,37(4):669-674.(YANG Ya-jing,LI Xiao-ya,JING Hongda. Characteristics of Thermoacoustic Oscillations in Magnesium-Based Water Ramjet[J]. Journal of Propulsion Technology,2016,37(4):669-674.)
[16] Abbud-Madrid A,Modak A,Branch M C,et al. Combustion of Magnesium with Carbon Dioxide and Carbon Monoxide at Low Gravity[J]. Journal of Propulsion and Power,2001,17(4):852-859.
[17] Rayleigh. The Theory of Sound[M]. New York:Dover Publications,1945.
[2] Boiko V M,Lotov V V,Papyrin A N. Ignition of Gas Suspensions of Metallic Powders in Reflected Shock Waves[J]. Combustion Explosion and Shock Waves,1989,25(2):193-199.
[3] Wickman J. In-situ Mars Rocket and Jet Engines Burning Carbon Dioxide[C]. Los Angeles:35th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit,1999.
[4] Linnell J,Miller T. A Preliminary Design of a Magnesium Fueled Martian Ramjet Engine[C]. Indianapolis:38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit,2002.
[5] Glassman I. Metal Combustion Processes[J]. American Rocket Society,1959,6(2):311-23.
[6] Liang Y,Beckstead M. Numerical Simulation of QuasiSteady,Single Aluminum Particle Combustion in Air[C]. Reno:The 36th AIAA Aerospace Sciences Meeting and Exhibit,1998.
[7]林长津,王浩,朱晨光,等.镁金属微粒非快速燃烧反应模型及数值分析[J].含能材料,2015,23(6):573-577.
[8]潘宏亮,李逢春,王克秀.镁粉粒度对点火延迟影响的实验和理论研究[J].推进技术,1987,8(3).(PANG Hong-liang,LI Feng-chun,WANG Ke-xiu.Experimental and Theoretical Research about the Effects of Magnesium Powder Particle Size on Ignition Delay[J].Journal of Propulsion Technology,1987,8(3).)
[9] Abbud-Madrid A,Branch M,Daily J. On the Burning Behavior of Radiatively-Ignited Bulk Titanium and Magnesium in Low Gravity[C]. Reno:The 34th Aerospace Sciences Meeting and Exhibit,1996.
[10] Dreyer C B. Planar Laser Induced Fluorescence Measurements of Magnesium Oxide During Combustion of Magnesium with Oxygen and Carbon Dioxide[C]. Reno:The 39th Aerospace Sciences Meeting and Exhibit,2001.
[11] Goroshin S,Higgins A,Kamel M. Powdered Metals as Fuel for Hypersonic Ramjets[R]. AIAA 2001-3919.
[12]申慧君,夏智勋,胡建新,等.金属粉末燃料冲压发动机初步试验研究[J].固体火箭技术,2008,31(3):225-227.
[13]申慧君,夏智勋,胡建新,等.粉末燃料冲压发动机自维持稳定燃烧试验研究[J].固体火箭技术,2009,32(2):145-149.
[14] Lieuwen T C,Vigor Yang. Combustion Instabilities in Gas Turbine Engines[M]. Texas:American Institute of Astronautics,2005.
[15]杨亚晶,李晓亚,荆宏达.镁基燃料水冲压发动机的热声振荡特性研究[J].推进技术,2016,37(4):669-674.(YANG Ya-jing,LI Xiao-ya,JING Hongda. Characteristics of Thermoacoustic Oscillations in Magnesium-Based Water Ramjet[J]. Journal of Propulsion Technology,2016,37(4):669-674.)
[16] Abbud-Madrid A,Modak A,Branch M C,et al. Combustion of Magnesium with Carbon Dioxide and Carbon Monoxide at Low Gravity[J]. Journal of Propulsion and Power,2001,17(4):852-859.
[17] Rayleigh. The Theory of Sound[M]. New York:Dover Publications,1945.