A phenomenological model for predicting the vortex-induced motion (VIM) of a single-column platform with non- linear stiffness has been proposed. The VIM model is based on the couple of the Duffing-van der Pol oscilla...A phenomenological model for predicting the vortex-induced motion (VIM) of a single-column platform with non- linear stiffness has been proposed. The VIM model is based on the couple of the Duffing-van der Pol oscillators and the motion equations with non-linear terms. The model with liner stiffness is presented for comparison and their results are compared with the experiments in order to calibrate the model. The computed results show that the predicted VIM amplitudes and periods of oscillation are in qualitative agreements with the experimental data. Compared with the results with linear stiffness, it is found that the application of non-linear stiffness causes the significant reductions in the in-line and transverse motion amplitudes. Under the non-linear stiffness constraint, the lock-in behavior is still identified at 8<Ur<15, and the trajectories of the VIM on the xy plane with eight-figure patterns are maintained. The results with different non-linear geometrically parameters show that both in-line and transverse non-linear characteristics can significantly affect the predict in-line and transverse motion amplitudes. Furthermore, the computed results for different aspect ratios indicate that the in-line and transverse motion amplitudes increase with the growth of aspect ratio, and the range of lock-in region is enlarged for the large aspect ratio.展开更多
To realize the industrialization of the novel single-column air separation process proposed in previous work,steady-state simulation for four different configurations of the single-column process with ternary(nitrogen...To realize the industrialization of the novel single-column air separation process proposed in previous work,steady-state simulation for four different configurations of the single-column process with ternary(nitrogen,oxygen and argon)is developed.Then,exergy analysis of the single-column processes is also carried out and compared with the conventional double-column air separation process at the same capacity.Furthermore,based on the steady-state simulation of single-column processes,the different heat exchanger networks(HENs)for the main heat exchanger and subcooler in each process are designed.To obtain better performance for this novel process,optimization of process configuration and operation is investigated.The optimal condition and configuration for this process is consisted as:feedstock is divided into two streams and the reflux nitrogen is compressed at the approximate temperature of 301 K.In addition,HEN is optimized to minimize the utilities.HENs without utilities are obtained for the four different configurations of single-column process.Furthermore,capital costs of the HEN for different cases are estimated and compared.展开更多
This paper describes the study of a single-column structure used as well-head platform. In order to check the reliability of computation theory and programme, model tests have been carried out. The paper introduces th...This paper describes the study of a single-column structure used as well-head platform. In order to check the reliability of computation theory and programme, model tests have been carried out. The paper introduces the conclusion of tests and the dynamic properties of single-column platform are obtained.展开更多
In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased...In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased. The advantages of the single-column structure compared with ordinary jacket structure are explained. A dynamic analysis of this type of structure is made and some problems related to dynamic analysis are solved. In order to check the reliability of computation theory and programme, model tests have been carried out. However, as space is limited, the conclusion of tests will be introduced in another paper. Therefore, this type of structure is applicable for proctical engineering.展开更多
A single-column model(SCM)is developed in the regional climate model RegCM4.The evolution of a dry convection boundary layer(DCBL)is used to evaluate this SCM.Moreover,four planetary boundary layer(PBL)schemes,namely ...A single-column model(SCM)is developed in the regional climate model RegCM4.The evolution of a dry convection boundary layer(DCBL)is used to evaluate this SCM.Moreover,four planetary boundary layer(PBL)schemes,namely the Holtslag-Boville scheme(HB),Yonsei University scheme(YSU),and two University of Washington schemes(UW01,Grenier-Bretherton-Mc Caa scheme and UW09,Bretherton-Park scheme),are compared by using the SCM approach.A large-eddy simulation(LES)of the DCBL is performed as a benchmark to examine how well a PBL parameterization scheme reproduces the LES results,and several diagnostic outputs are compared to evaluate the schemes.The results show that the SCM is properly constructed.In general,with the DCBL case,the YSU scheme performs best for reproducing the LES results,which include well-mixed features and vertical sensible heat fluxes;the simulated wind speed,turbulent kinetic energy,entrainment flux,and height of the entrainment zone are all underestimated in the UW09;the UW01 has all those biases of the UW09 but larger,and the simulated potential temperature is not well mixed;the HB is the least skillful scheme,by which the PBL height,entrainment flux,height of the entrainment zone,and the vertical gradients within the mixed layer are all overestimated,and a inversion layer near the top of the surface layer is wrongly simulated.Although more cases and further testing are required,these simulations show encouraging results towards the use of this SCM framework for evaluating the simulated physical processes by the RegCM4.展开更多
In order to directly separate trivalent minor actinides （MA： Am, Cm） from fission products （FP） containing rare earths （RE） in high level radioactive liquid waste （HLLW）, the authors have challenged to develo...In order to directly separate trivalent minor actinides （MA： Am, Cm） from fission products （FP） containing rare earths （RE） in high level radioactive liquid waste （HLLW）, the authors have challenged to develop a simplified MA separation process by extraction chromatography using a single column. Attention has been paid to a new type of nitrogen-donor ligands, R-BTP （2,6-bis（5,6-dialkyl-1,2,4-triazin-3-yl） pyridine, R： alkyl group） as an extractant because it shows high extraction selectivity for Am（Ⅲ） over RE（Ⅲ）. It is known that the R-BTP ligands show different properties such as adsorbability and stability by hav- ing different alkyl groups. Therefore, some novel adsorbents were prepared by impregnating different types of R-BTP ligands （isohexyl-, isoheptyl- and cyheptyl-BTP） and a similar ligand to the R-BTP, ATP （2,6-bis（l-aryl-lH-tetrazol-5-yl）pyridines）, into the porous silica/polymer support （SiOrP particles）. This work deals with comparison in adsorption and desorption prop- erties of Am and some FP in HNO3 solution onto such R-BTP type adsorbents, as well as chemical and radiolytic stability of the adsorbents. Then the possibility of a single-column separation of MA from main FP was pursued by evaluating the results of column experiments using the most promising adsorbent （isohexyl-BTP/SiO2-P） under temperature control. In addition, elu- tion behaviors of U and Pd were also estimated.展开更多
Use of wordprocessing software It is important that the file be saved in the native format of the wordprocessor used. The text should be in single-column format. Keep the layout of the text as simple as possible. Most...Use of wordprocessing software It is important that the file be saved in the native format of the wordprocessor used. The text should be in single-column format. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. In particular, do not use the wordprocessor’s options to justify text or to hyphenate words. However, do use bold face, italics, subscripts, superscripts etc.展开更多
A single-column model is constructed based on parameterizations inherited from the Finite-volume/Spectral Atmospheric Model F/SAMIL and tested in simulations of tropical convective systems. Two representative convecti...A single-column model is constructed based on parameterizations inherited from the Finite-volume/Spectral Atmospheric Model F/SAMIL and tested in simulations of tropical convective systems. Two representative convection schemes are compared in terms of their performances on precipitation types, individual physical tendencies, and temperature and moisture fields. The main difference between the two selected schemes is in their representation of entraining/detraining process. The Tiedtke scheme assumes bulk entrainment, while the Zhang–Mc Farlane scheme parameterizes entrainment/detrainment rates under the spectrum concept. Large-scale forcing and verification data are taken from the GATE phase III field campaign, during which abundant convective events were observed. Given the same triggering function and closure assumption, results show that entrainment/detrainment representation remains the dominant factor on the simulation of cumulus mass flux and of temperature and moisture fields. By analyzing sources and sinks of heat and moisture, this study reveals how parameterization components compensate for each other and make model results insensitive to parameterization changes in certain fields, thus suggesting the need to treat parameterizations as systems rather than individual components.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51679138)the 1000 Young Talent Program(Grant No.15Z127060020)the National Basic Research Program of China(973 Program,Grant Nos.2015CB251203 and 2013CB036103)
文摘A phenomenological model for predicting the vortex-induced motion (VIM) of a single-column platform with non- linear stiffness has been proposed. The VIM model is based on the couple of the Duffing-van der Pol oscillators and the motion equations with non-linear terms. The model with liner stiffness is presented for comparison and their results are compared with the experiments in order to calibrate the model. The computed results show that the predicted VIM amplitudes and periods of oscillation are in qualitative agreements with the experimental data. Compared with the results with linear stiffness, it is found that the application of non-linear stiffness causes the significant reductions in the in-line and transverse motion amplitudes. Under the non-linear stiffness constraint, the lock-in behavior is still identified at 8<Ur<15, and the trajectories of the VIM on the xy plane with eight-figure patterns are maintained. The results with different non-linear geometrically parameters show that both in-line and transverse non-linear characteristics can significantly affect the predict in-line and transverse motion amplitudes. Furthermore, the computed results for different aspect ratios indicate that the in-line and transverse motion amplitudes increase with the growth of aspect ratio, and the range of lock-in region is enlarged for the large aspect ratio.
基金Supported by the National Natural Science Foundation of China(21576228)
文摘To realize the industrialization of the novel single-column air separation process proposed in previous work,steady-state simulation for four different configurations of the single-column process with ternary(nitrogen,oxygen and argon)is developed.Then,exergy analysis of the single-column processes is also carried out and compared with the conventional double-column air separation process at the same capacity.Furthermore,based on the steady-state simulation of single-column processes,the different heat exchanger networks(HENs)for the main heat exchanger and subcooler in each process are designed.To obtain better performance for this novel process,optimization of process configuration and operation is investigated.The optimal condition and configuration for this process is consisted as:feedstock is divided into two streams and the reflux nitrogen is compressed at the approximate temperature of 301 K.In addition,HEN is optimized to minimize the utilities.HENs without utilities are obtained for the four different configurations of single-column process.Furthermore,capital costs of the HEN for different cases are estimated and compared.
文摘This paper describes the study of a single-column structure used as well-head platform. In order to check the reliability of computation theory and programme, model tests have been carried out. The paper introduces the conclusion of tests and the dynamic properties of single-column platform are obtained.
文摘In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased. The advantages of the single-column structure compared with ordinary jacket structure are explained. A dynamic analysis of this type of structure is made and some problems related to dynamic analysis are solved. In order to check the reliability of computation theory and programme, model tests have been carried out. However, as space is limited, the conclusion of tests will be introduced in another paper. Therefore, this type of structure is applicable for proctical engineering.
基金National Key R&D Program of China(2018YFA06063012020YFA0608201+1 种基金2017YFA0605004)National Natural Science Foundation of China(41405101)。
文摘A single-column model(SCM)is developed in the regional climate model RegCM4.The evolution of a dry convection boundary layer(DCBL)is used to evaluate this SCM.Moreover,four planetary boundary layer(PBL)schemes,namely the Holtslag-Boville scheme(HB),Yonsei University scheme(YSU),and two University of Washington schemes(UW01,Grenier-Bretherton-Mc Caa scheme and UW09,Bretherton-Park scheme),are compared by using the SCM approach.A large-eddy simulation(LES)of the DCBL is performed as a benchmark to examine how well a PBL parameterization scheme reproduces the LES results,and several diagnostic outputs are compared to evaluate the schemes.The results show that the SCM is properly constructed.In general,with the DCBL case,the YSU scheme performs best for reproducing the LES results,which include well-mixed features and vertical sensible heat fluxes;the simulated wind speed,turbulent kinetic energy,entrainment flux,and height of the entrainment zone are all underestimated in the UW09;the UW01 has all those biases of the UW09 but larger,and the simulated potential temperature is not well mixed;the HB is the least skillful scheme,by which the PBL height,entrainment flux,height of the entrainment zone,and the vertical gradients within the mixed layer are all overestimated,and a inversion layer near the top of the surface layer is wrongly simulated.Although more cases and further testing are required,these simulations show encouraging results towards the use of this SCM framework for evaluating the simulated physical processes by the RegCM4.
文摘In order to directly separate trivalent minor actinides （MA： Am, Cm） from fission products （FP） containing rare earths （RE） in high level radioactive liquid waste （HLLW）, the authors have challenged to develop a simplified MA separation process by extraction chromatography using a single column. Attention has been paid to a new type of nitrogen-donor ligands, R-BTP （2,6-bis（5,6-dialkyl-1,2,4-triazin-3-yl） pyridine, R： alkyl group） as an extractant because it shows high extraction selectivity for Am（Ⅲ） over RE（Ⅲ）. It is known that the R-BTP ligands show different properties such as adsorbability and stability by hav- ing different alkyl groups. Therefore, some novel adsorbents were prepared by impregnating different types of R-BTP ligands （isohexyl-, isoheptyl- and cyheptyl-BTP） and a similar ligand to the R-BTP, ATP （2,6-bis（l-aryl-lH-tetrazol-5-yl）pyridines）, into the porous silica/polymer support （SiOrP particles）. This work deals with comparison in adsorption and desorption prop- erties of Am and some FP in HNO3 solution onto such R-BTP type adsorbents, as well as chemical and radiolytic stability of the adsorbents. Then the possibility of a single-column separation of MA from main FP was pursued by evaluating the results of column experiments using the most promising adsorbent （isohexyl-BTP/SiO2-P） under temperature control. In addition, elu- tion behaviors of U and Pd were also estimated.
文摘Use of wordprocessing software It is important that the file be saved in the native format of the wordprocessor used. The text should be in single-column format. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. In particular, do not use the wordprocessor’s options to justify text or to hyphenate words. However, do use bold face, italics, subscripts, superscripts etc.
基金jointly supported by the National Natural Science Foundation of China(41305102)the National Basic Research Program of China(2014CB441202,2013CB955803)
文摘A single-column model is constructed based on parameterizations inherited from the Finite-volume/Spectral Atmospheric Model F/SAMIL and tested in simulations of tropical convective systems. Two representative convection schemes are compared in terms of their performances on precipitation types, individual physical tendencies, and temperature and moisture fields. The main difference between the two selected schemes is in their representation of entraining/detraining process. The Tiedtke scheme assumes bulk entrainment, while the Zhang–Mc Farlane scheme parameterizes entrainment/detrainment rates under the spectrum concept. Large-scale forcing and verification data are taken from the GATE phase III field campaign, during which abundant convective events were observed. Given the same triggering function and closure assumption, results show that entrainment/detrainment representation remains the dominant factor on the simulation of cumulus mass flux and of temperature and moisture fields. By analyzing sources and sinks of heat and moisture, this study reveals how parameterization components compensate for each other and make model results insensitive to parameterization changes in certain fields, thus suggesting the need to treat parameterizations as systems rather than individual components.
