In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurizatio...In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurization. Based on experimental data,a model of mass-transfer and reaction of the sulfur dioxide chemical absorption in the rotating packed bed reactor is proposed according to the film-theory. It can be used to predict the performance of the total absorption rate and the enhancement factor of the sulfur dioxide and oxygen simultaneous absorption in the rotating packed bed reactor.The prediction of the model is consistent with the experimental result varying operating conditions, and the relative error between experimental result and predicted result is below 12%. Some interesting potential projects of simultaneous absorption of sulfur dioxide and oxygen in the rotating packed bed reactor are also discussed.展开更多
规整填料内鼓泡流动现象的研究对于开发新型气液传质与反应设备具有重要的指导作用。为此应用VOF(Volume of Fluid)多相流模型建立了描述规整填料内部鼓泡流动现象的二维模型,模型中考虑了影响气液两相流动的两个重要作用力:表面张力和...规整填料内鼓泡流动现象的研究对于开发新型气液传质与反应设备具有重要的指导作用。为此应用VOF(Volume of Fluid)多相流模型建立了描述规整填料内部鼓泡流动现象的二维模型,模型中考虑了影响气液两相流动的两个重要作用力:表面张力和气液相间作用力。模拟计算结果显示,气泡在上升过程中自身振荡,随着入口气速的增大,气泡形变程度增大,并且伴有气泡聚并现象发生。气泡上升过程中,气泡周围液体的速度增大,并且形成大小不同的旋涡结构,单点速度值的波动程度随气体入口速度的增大而增大。展开更多
In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consid...In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics Reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.展开更多
研制可快速、在线分析挥发性有机物(volatile organic compounds,VOCs)的质谱仪器是现代气态有机质谱的重要发展方向。本研究自行研制了小型高性能质子转移反应飞行时间质谱仪(proton transfer reaction time of flight mass spectromet...研制可快速、在线分析挥发性有机物(volatile organic compounds,VOCs)的质谱仪器是现代气态有机质谱的重要发展方向。本研究自行研制了小型高性能质子转移反应飞行时间质谱仪(proton transfer reaction time of flight mass spectrometry,PTR-TOF MS),仪器采用结构简单可靠的空心阴极放电源作为水蒸气电离源,以产生水合质子;线性漂移管作为分子离子反应管。该离子源产生的水合离子纯度高,为水合离子与VOCs的分子离子反应提供可控的反应条件。传输接口部分使用射频四极杆作为离子导向装置,以提高离子传输效率;配合小尺寸飞行时间质量分析器,兼顾仪器的灵敏度与分辨率。质子转移反应的测定原理使该仪器可以分析除少数烷烃外的绝大多数VOCs,同时分析过程不受空气组分的影响。分子离子峰为主的产物离子形式使谱图便于解析,适合高通量分析。测试结果表明,该仪器在m/z 115处全高半峰宽(full width half maximum,FWHM)分辨率优于2500,对丙酮、苯、甲苯的检出限在6×10^(-12)~9.6×10^(-11) mol/mol之间。将该仪器应用于人体呼吸气的成分分析,取得了良好的结果。展开更多
文摘In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurization. Based on experimental data,a model of mass-transfer and reaction of the sulfur dioxide chemical absorption in the rotating packed bed reactor is proposed according to the film-theory. It can be used to predict the performance of the total absorption rate and the enhancement factor of the sulfur dioxide and oxygen simultaneous absorption in the rotating packed bed reactor.The prediction of the model is consistent with the experimental result varying operating conditions, and the relative error between experimental result and predicted result is below 12%. Some interesting potential projects of simultaneous absorption of sulfur dioxide and oxygen in the rotating packed bed reactor are also discussed.
文摘规整填料内鼓泡流动现象的研究对于开发新型气液传质与反应设备具有重要的指导作用。为此应用VOF(Volume of Fluid)多相流模型建立了描述规整填料内部鼓泡流动现象的二维模型,模型中考虑了影响气液两相流动的两个重要作用力:表面张力和气液相间作用力。模拟计算结果显示,气泡在上升过程中自身振荡,随着入口气速的增大,气泡形变程度增大,并且伴有气泡聚并现象发生。气泡上升过程中,气泡周围液体的速度增大,并且形成大小不同的旋涡结构,单点速度值的波动程度随气体入口速度的增大而增大。
文摘In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics Reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.
文摘研制可快速、在线分析挥发性有机物(volatile organic compounds,VOCs)的质谱仪器是现代气态有机质谱的重要发展方向。本研究自行研制了小型高性能质子转移反应飞行时间质谱仪(proton transfer reaction time of flight mass spectrometry,PTR-TOF MS),仪器采用结构简单可靠的空心阴极放电源作为水蒸气电离源,以产生水合质子;线性漂移管作为分子离子反应管。该离子源产生的水合离子纯度高,为水合离子与VOCs的分子离子反应提供可控的反应条件。传输接口部分使用射频四极杆作为离子导向装置,以提高离子传输效率;配合小尺寸飞行时间质量分析器,兼顾仪器的灵敏度与分辨率。质子转移反应的测定原理使该仪器可以分析除少数烷烃外的绝大多数VOCs,同时分析过程不受空气组分的影响。分子离子峰为主的产物离子形式使谱图便于解析,适合高通量分析。测试结果表明,该仪器在m/z 115处全高半峰宽(full width half maximum,FWHM)分辨率优于2500,对丙酮、苯、甲苯的检出限在6×10^(-12)~9.6×10^(-11) mol/mol之间。将该仪器应用于人体呼吸气的成分分析,取得了良好的结果。
