文章使用超大涡模拟(very large eddy simulation,VLES)方法耦合离散相模型对液体射流在横向气流中雾化过程进行模拟,并对比多套网格尺度下不同湍流模型的预测结果。结果表明,VLES方法能够较为准确地预测横向射流的基本形态及参数。相...文章使用超大涡模拟(very large eddy simulation,VLES)方法耦合离散相模型对液体射流在横向气流中雾化过程进行模拟,并对比多套网格尺度下不同湍流模型的预测结果。结果表明,VLES方法能够较为准确地预测横向射流的基本形态及参数。相对其他湍流模型在不同网格尺度下模拟结果波动明显,VLES方法对网格尺寸敏感度较低,并在模拟流场流动细节方面能够捕捉到更多液柱破碎的表面结构,较雷诺平均(Reynolds-averaged Navier-Stokes,RANS)模拟方法有显著优势,且计算量比大涡模拟(large eddy simulation,LES)方法大大降低,在工程实际运用中是一种颇具潜力的数值研究方法。展开更多
Natural gas is widely regarded as an efficient,relatively clean,and economically viable energy source.Its safe operation and continuous supply through pipeline infrastructure has led to its prominence in the energy se...Natural gas is widely regarded as an efficient,relatively clean,and economically viable energy source.Its safe operation and continuous supply through pipeline infrastructure has led to its prominence in the energy sector.Methanol plays an important role in the natural gas industry,typically serving as a solvent or hydrate inhibitor.Therefore,the accurate estimation of thermodynamic properties for methane/methanol binary is extremely important to optimise the operating parameter,maximise the dehydration effect,and reduce the cost.As the Helmholtz energy equation of state is expected to offer high accuracy in predicting the vapour-liquid equilibrium of methane/methanol binary,four reducing parameters were derived based on collected experimental data.Additionally,the sensitivities of various reducing parameter combinations were simultaneously investigated.The results demonstrated a strong agreement between predicted fractions and experimental data,with the UMADs(uncertainty-weighted mean absolute deviation)of 3.484 and 0.665 for liquid and vapour phases,respectively.Meanwhile,it is deemed“very likely”,“likely”,and“unlikely”to achieve acceptable prediction for 3-parameter optimisation,2-parameter optimisation and,1-parameter optimisation,respectively.展开更多
本文将一种VLES(Very Large Eddy Simulation)模型引入到动网格数值计算中,并验证了VLES模型用于模拟类似振动圆柱绕流的动边界问题的有效性。数值求解了不同振幅和频率下非稳态振动圆柱绕流问题。研究表明:随着振幅和激励频率的增加,...本文将一种VLES(Very Large Eddy Simulation)模型引入到动网格数值计算中,并验证了VLES模型用于模拟类似振动圆柱绕流的动边界问题的有效性。数值求解了不同振幅和频率下非稳态振动圆柱绕流问题。研究表明:随着振幅和激励频率的增加,绕圆柱流动涡脱离形式从2S模式转换到2P0模式,再到P+S模式。在高振幅和激励频率比fe/fs=0.95时,涡脱离形式却表现为2P0模式到P+S模式的过渡状态,振动圆柱在上升或下降过程中涡的脱离造成在每个周期升力曲线的左右侧发生不规则的"跳动"现象,尽管脱落涡可能为涡对或者单涡.展开更多
The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robi...The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robinson equation, a traditional cubic equation of state widely employed in chemical industries, as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross-Sadowski. By correlation of the binary inter- action parameters of these equations, the measured vapor-liquid equilibrium data can be accurately predicted. Thus, this work shows that these models are able to represent the experimental data for systems with associating comoounds via hydrogen bonding.展开更多
The vapor-liquid equilibrium of Dimethyl Carbonate-Methanol-Furfural under atmospheric pressure from DMC-CH 3OH,DMCC 5H 4O 2,CH 3OH-C 5H 4O 2 binary systematic VLE data is calculated,by using C ++(VC6.0) pr...The vapor-liquid equilibrium of Dimethyl Carbonate-Methanol-Furfural under atmospheric pressure from DMC-CH 3OH,DMCC 5H 4O 2,CH 3OH-C 5H 4O 2 binary systematic VLE data is calculated,by using C ++(VC6.0) programming language and Wilson equation.It provided important VLE data to set up mathematic models of extraction-rectifying separation of DMC and methanol by using furfural as extraction reagent.So the results can be used for chemical engineering calculation.展开更多
The atmospheric vapor-liquid equilibrium system of diethyl oxalate-ethanol was reproduced through the visual basic (VB6.0) computer language by using the Wilson, NRTL and the UNIFAC equation. The results of the three ...The atmospheric vapor-liquid equilibrium system of diethyl oxalate-ethanol was reproduced through the visual basic (VB6.0) computer language by using the Wilson, NRTL and the UNIFAC equation. The results of the three methods are all that could be desired. The calculated results of three different models are in perfect agreement with experiment data. The calculated results of UNIFAC equation is the optimum in several models. So the results can be used for chemical engineering calculation.展开更多
This research study measures the support for learners through the use of a Virtual Learning Environment project website. The website prepares, assists and supports the learners through their Mechanical Engineering Pro...This research study measures the support for learners through the use of a Virtual Learning Environment project website. The website prepares, assists and supports the learners through their Mechanical Engineering Projects in an accredited academic programme. The research question answered was "Is the VLE website helpful to learners in the final years of mechanical engineering projects?" The research focuses on the learners' experiences of using the project website and explores their views regarding the website. The literature relating to the study indicates that similar programmes have had positive results in relation to the adoption of VLEs to support learners.The data collection process involved an initial questionnaire about the website for the quantitative analysis. Thirty-nine project learners from the third and fourth years of the Mechanical Engineering programme participated in the questionnaires. The analysis of the questionnaire results indicated that the project website VLE was very helpful to learners completing their Mechanical Engineering projects. They all used the website for different aspects of the project but they still wanted a lecturer or lecturers to consult with for problems during the course of the project. The kinesthetic learning achieved in the project modules cannot be replicated or replaced by any virtual learning environment. The website afforded the learner to be better prepared for the project start in September. It gives the learner another resource to refer to when they were working at home, during the holidays or when they come to a particular part of the project. The website also teaches the learner to use the internet, videos, screencasts, tutorials, etc. to help them to complete the project.The website has enhanced student learning, motivation, earlier starts to project, peer learning and has improved the quality of projects.展开更多
Extractive agents of extractive distillation separation for mixtures of dichlorobenzene were analyzed and compared, gas-liquid equilibrium data （VLE data） was measured for dichlorobenzene and diphenylamine, the appr...Extractive agents of extractive distillation separation for mixtures of dichlorobenzene were analyzed and compared, gas-liquid equilibrium data （VLE data） was measured for dichlorobenzene and diphenylamine, the appropriate extractive agent was selected by relatively volatility, the temperature was studied on the effect of extractive separation. VLE data was measured for dichlorobenzene, the parameters were simulated in Wilson equation. The infinite dilute activity coefficient of dichlorobenzene in diphenylamine were measured by chromatogram apparatus, the model parameters were correlated by the single parameter method for dichlorobenzene and diphenyl -amine, VLE data of m-dichlorobenzene-p- dichlorobenzene -o-dichlorobenzene-diphenylamine system was measured and calculated by six part model parameters. The results of correlation and experiment were provided a basis for study of extractive distillation simulation and experiment in this work.展开更多
A simple extension of cubic equations of state(EOS)to polymer systems has been proposed.The So-ave-Redlich-Kwong(SRK)EOS was taken as a prototype to be used to describe the PVT behavior of polymer melts in a wide temp...A simple extension of cubic equations of state(EOS)to polymer systems has been proposed.The So-ave-Redlich-Kwong(SRK)EOS was taken as a prototype to be used to describe the PVT behavior of polymer melts in a wide temperature and pressure range.Combined with a modified Huron-Vidal gE-mixing rule it was applied for modeling vapor-liquid equilibria of polymer-solvent solutions and the solubility of supercritical gases in polymer melts.Satisfactory results are obtained.展开更多
基金supported financially by the National Natural Science Foundation of China(52202434)the National Natural Science Foundation of Ningbo(2023J275).
文摘Natural gas is widely regarded as an efficient,relatively clean,and economically viable energy source.Its safe operation and continuous supply through pipeline infrastructure has led to its prominence in the energy sector.Methanol plays an important role in the natural gas industry,typically serving as a solvent or hydrate inhibitor.Therefore,the accurate estimation of thermodynamic properties for methane/methanol binary is extremely important to optimise the operating parameter,maximise the dehydration effect,and reduce the cost.As the Helmholtz energy equation of state is expected to offer high accuracy in predicting the vapour-liquid equilibrium of methane/methanol binary,four reducing parameters were derived based on collected experimental data.Additionally,the sensitivities of various reducing parameter combinations were simultaneously investigated.The results demonstrated a strong agreement between predicted fractions and experimental data,with the UMADs(uncertainty-weighted mean absolute deviation)of 3.484 and 0.665 for liquid and vapour phases,respectively.Meanwhile,it is deemed“very likely”,“likely”,and“unlikely”to achieve acceptable prediction for 3-parameter optimisation,2-parameter optimisation and,1-parameter optimisation,respectively.
文摘本文将一种VLES(Very Large Eddy Simulation)模型引入到动网格数值计算中,并验证了VLES模型用于模拟类似振动圆柱绕流的动边界问题的有效性。数值求解了不同振幅和频率下非稳态振动圆柱绕流问题。研究表明:随着振幅和激励频率的增加,绕圆柱流动涡脱离形式从2S模式转换到2P0模式,再到P+S模式。在高振幅和激励频率比fe/fs=0.95时,涡脱离形式却表现为2P0模式到P+S模式的过渡状态,振动圆柱在上升或下降过程中涡的脱离造成在每个周期升力曲线的左右侧发生不规则的"跳动"现象,尽管脱落涡可能为涡对或者单涡.
文摘The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robinson equation, a traditional cubic equation of state widely employed in chemical industries, as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross-Sadowski. By correlation of the binary inter- action parameters of these equations, the measured vapor-liquid equilibrium data can be accurately predicted. Thus, this work shows that these models are able to represent the experimental data for systems with associating comoounds via hydrogen bonding.
文摘The vapor-liquid equilibrium of Dimethyl Carbonate-Methanol-Furfural under atmospheric pressure from DMC-CH 3OH,DMCC 5H 4O 2,CH 3OH-C 5H 4O 2 binary systematic VLE data is calculated,by using C ++(VC6.0) programming language and Wilson equation.It provided important VLE data to set up mathematic models of extraction-rectifying separation of DMC and methanol by using furfural as extraction reagent.So the results can be used for chemical engineering calculation.
文摘The atmospheric vapor-liquid equilibrium system of diethyl oxalate-ethanol was reproduced through the visual basic (VB6.0) computer language by using the Wilson, NRTL and the UNIFAC equation. The results of the three methods are all that could be desired. The calculated results of three different models are in perfect agreement with experiment data. The calculated results of UNIFAC equation is the optimum in several models. So the results can be used for chemical engineering calculation.
文摘This research study measures the support for learners through the use of a Virtual Learning Environment project website. The website prepares, assists and supports the learners through their Mechanical Engineering Projects in an accredited academic programme. The research question answered was "Is the VLE website helpful to learners in the final years of mechanical engineering projects?" The research focuses on the learners' experiences of using the project website and explores their views regarding the website. The literature relating to the study indicates that similar programmes have had positive results in relation to the adoption of VLEs to support learners.The data collection process involved an initial questionnaire about the website for the quantitative analysis. Thirty-nine project learners from the third and fourth years of the Mechanical Engineering programme participated in the questionnaires. The analysis of the questionnaire results indicated that the project website VLE was very helpful to learners completing their Mechanical Engineering projects. They all used the website for different aspects of the project but they still wanted a lecturer or lecturers to consult with for problems during the course of the project. The kinesthetic learning achieved in the project modules cannot be replicated or replaced by any virtual learning environment. The website afforded the learner to be better prepared for the project start in September. It gives the learner another resource to refer to when they were working at home, during the holidays or when they come to a particular part of the project. The website also teaches the learner to use the internet, videos, screencasts, tutorials, etc. to help them to complete the project.The website has enhanced student learning, motivation, earlier starts to project, peer learning and has improved the quality of projects.
文摘Extractive agents of extractive distillation separation for mixtures of dichlorobenzene were analyzed and compared, gas-liquid equilibrium data （VLE data） was measured for dichlorobenzene and diphenylamine, the appropriate extractive agent was selected by relatively volatility, the temperature was studied on the effect of extractive separation. VLE data was measured for dichlorobenzene, the parameters were simulated in Wilson equation. The infinite dilute activity coefficient of dichlorobenzene in diphenylamine were measured by chromatogram apparatus, the model parameters were correlated by the single parameter method for dichlorobenzene and diphenyl -amine, VLE data of m-dichlorobenzene-p- dichlorobenzene -o-dichlorobenzene-diphenylamine system was measured and calculated by six part model parameters. The results of correlation and experiment were provided a basis for study of extractive distillation simulation and experiment in this work.
基金Supported by the Zhejiang Provincial Foundation for Returned Scholarsthe Scientific Research Foundation of the State Human Resource Ministry.
文摘A simple extension of cubic equations of state(EOS)to polymer systems has been proposed.The So-ave-Redlich-Kwong(SRK)EOS was taken as a prototype to be used to describe the PVT behavior of polymer melts in a wide temperature and pressure range.Combined with a modified Huron-Vidal gE-mixing rule it was applied for modeling vapor-liquid equilibria of polymer-solvent solutions and the solubility of supercritical gases in polymer melts.Satisfactory results are obtained.
