In a fusion reactor, the edge localized mode(ELM) coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power a...In a fusion reactor, the edge localized mode(ELM) coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power and improve its mitigating ability. The coil works in a high-temperature,high-nuclear-heat and high-magnetic-field environment. Due to the existence of outer superconducting coils, the coil is subjected to an alternating electromagnetic force induced by its own alternating current and the outer magnetic field. The design goal for the ELM coil is to maintain its structural integrity in the multi-physical field. Taking as an example the middle ELM coil(with flexible supports) of ITER(the International Thermonuclear Fusion Reactor), an electromagnetic–thermal–structural coupling analysis is carried out using ANSYS. The results show that the flexible supports help the three-layer casing meet the static and fatigue design requirements. The structural design of the middle ELM coil is reasonable and feasible. The work described in this paper provides the theoretical basis and method for ELM coil design.展开更多
With the high speed, the rotor of magnetically suspended permanent magnet synchronous motor(MSPMSM) suffers great thermal stress and mechanical stress resulting from the temperature rise problem caused by rotor losses...With the high speed, the rotor of magnetically suspended permanent magnet synchronous motor(MSPMSM) suffers great thermal stress and mechanical stress resulting from the temperature rise problem caused by rotor losses, which leads to instability and inefficiency.In this paper, the mechanical–temperature field coupling analysis is conducted to analyze the relationship between the temperature field and structure, and multi-objective optimization of a rotor is performed to improve the design reliability and efficiency. Firstly, the temperature field is calculated by the 2 D finite element model of MSPMSM and the method of applying the 2 D temperature result to the 3 D finite element model of the motor rotor equivalently is proposed. Then the thermal–structure coupling analysis is processed through mathematic method and finite element method(FEM),in which the 3 D finite element model is established precisely in a way and approaches the practical operation state further. Moreover, the impact produced by the temperature and structure on the mechanical strength is analyzed in detail. Finally, the optimization mathematical model of the motor rotor is established with Sequential Quadratic Programming-NLPQL selected in the optimization scheme. Through optimization, the strength of the components in the motor rotor increases obviously and satisfies the design requirement, which to a great extend enhances the service life of the MSPMSM rotor.展开更多
This work presents a numerical investigation of the thermal–fluid–structure coupling behavior of the liquid natural gas(LNG)transported in the flexible corrugated cryogenic hose.A three-dimensional model of the corr...This work presents a numerical investigation of the thermal–fluid–structure coupling behavior of the liquid natural gas(LNG)transported in the flexible corrugated cryogenic hose.A three-dimensional model of the corrugated hose structure composed of multiple layers of different materials is established and coupled with turbulent LNG flow and heat transfer models in the commercial software ANSYS Workbench.The flow transport behavior,heat transfer across the hose layers,and structural response caused by the flow are analyzed.Parametric studies are performed to evaluate the impacts of inlet flow rate and thermal conductivity of insulation material on the temperature and structural stress of the corrugated hose.The study found that,compared with a regular operating condition,higher inlet flow velocities not only suppress the heat gain of the LNG but also lower the flow-induced structural stress.The insulation layer exhibits excellent performance in maintaining the temperature at the fluid–structure interface,showing little temperature change with respect to material thermal conductivity and ambient temperature.The simulation results may contribute to the research and design of the flexible corrugated cryogenic hoses and provide guidance for safer and more efficient field operations.展开更多
An ITER torus cryo-pump housing (TCPH), which encloses a torus cryo-pump, is connected to a vacuum vessel (VV) by a set of associated double bellows. There are complicated loads due to two different operating stat...An ITER torus cryo-pump housing (TCPH), which encloses a torus cryo-pump, is connected to a vacuum vessel (VV) by a set of associated double bellows. There are complicated loads due to two different operating states (pumping and regeneration) and foreseeable accidents with the cryo-pump. This paper describes a thermal-structural coupled analysis of the present TCPH according to tho allowatfle stress criteria of RCC-MR, in which the worst cases and outcomes of various load combinations are obtained. Meanwhile, optimization of the structure has been carried oul, to obtain positive analysis results and an adequate safety margin.展开更多
The coupling behavior of the imbedded weapon store occurring between the local unsteady flow field round the store and the structure response on the processing of opening its bay-door is simulated by using numerical m...The coupling behavior of the imbedded weapon store occurring between the local unsteady flow field round the store and the structure response on the processing of opening its bay-door is simulated by using numerical method based on computational fluid mechanics(CFD).The transient aerodynamic behaviors when opening door under various flight altitudes and the corresponding structure deformation evolution in the unsteady flow fields are analyzed respectively and presented.The rules of aircraft attitude parameters′impacting to the responses of structure and the bay-door′s opening process are obtained by comparing with the analysis results.These rules can be applied to the structure design of bay-door and route specification of missile when disengaged and launched from within store.展开更多
Several types of coupling methods for resolving aerothermoelastic problems associated with hypersonic wings are summarized,and the appropriate coupling methods for engineering calculations are selected.Then,the calcul...Several types of coupling methods for resolving aerothermoelastic problems associated with hypersonic wings are summarized,and the appropriate coupling methods for engineering calculations are selected.Then,the calculation and analysis methods for the subdisciplines in this field are introduced,and the time step issue is discussed.A two-way-coupling rapid static aerothermoelastic method for analyzing hypersonic wings is proposed.This method considers thermal effects and is used to conduct an aerothermoelastic response analysis for a hypersonic wing.In addition,the aerodynamic force,heat flux,structural deformation and temperature field are obtained.The following three conclusions are drawn.First,the heating effect has a significant impact on the static aeroelastic response of hypersonic wings;therefore,thermal protection shields are essential.Second,the application of thermal protection shields reduces the differences in the calculation results between the one-and two-way-coupling methods.Third,hypersonic wings exhibit large thermal deformation under high-temperature environments,and in certain cases,the thermal deformation is even larger than the deformation caused by aerodynamic force.展开更多
A new calculating method of aerodynamic heating for unsteady hypersonic aircrafts with complex configuration is presented.This method,which considers the effects of high temperature chemical non-equilibrium and the he...A new calculating method of aerodynamic heating for unsteady hypersonic aircrafts with complex configuration is presented.This method,which considers the effects of high temperature chemical non-equilibrium and the heat transfer process in thermal protection structure,is based on the combination of the inviscid outerflow solution and the engineering method,where the Euler solver provides the flow parameters on boundary layer edge for engineering method in aerodynamic heating calculation.A high efficient interpolation technique,which can be applied to the fast computation of longtime aerodynamic heating for hypersonic aircraft,is developed for flying trajectory.In this paper,three hypersonic test cases are calculated,and the heat flux and temperature distribution of thermo-protection system are shown.The numerical results show the high efficiency of the developed method and the validation of thermal characteristics analysis on hypersonic aerodynamic heating.展开更多
反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanic...反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanical Engineers)规范中适用于核一级承压设备的相关标准和分析流程,对某型号反应堆的管道系统开展了结构强度校核及疲劳分析,数值结果表明:当前工况参数及出现次数叠加作用下管道系统的应力分类结果满足规范要求,不会出现不可逆的结构损伤,且关键结构不连续位置的疲劳累积使用因子均小于1,未出现累积使用因子超限问题。展开更多
Spacecraft flexible appendages may experience thermally induced vibrations(TIV)under sudden heating loads,which in consequence will be unable to complete their intended missions.Isogeometric analysis(IGA)utilizes,in a...Spacecraft flexible appendages may experience thermally induced vibrations(TIV)under sudden heating loads,which in consequence will be unable to complete their intended missions.Isogeometric analysis(IGA)utilizes,in an isoparametric concept,the same high order and high continuity non-uniform rational B-splines(NURBS)to represent both the geometry and the physical field of the structure.Compared to the traditional Lagrange polynomial based finite element method where only C0-continuity across elements can be achieved,IGA is geometrically exact and naturally fulfills the C1-continuity requirement of Euler–Bernoulli(EB)beam elements,therefore,does not need extra rotational degrees-of-freedom.In this paper,we present a thermally induced vibration analysis framework based on the isogeometric method where thermal and structural behaviors are coupled.We fully exploited the higher order,higher continuous and geometric exactness of the NURBS basis with both benchmarks and sophisticated problems.In particular,we studied the thermally induced vibrations of the Hubble Space Telescope(HST)solar panel where main factors influencing thermal flutters are studied,and where possible improvements of the analytical reference methods are discussed.Additionally,thermally induced vibrations of the thin-walled lenticular tubes are studied and two new configurations of the tube are proposed to effectively suppress the thermally induced vibrations.Numerical examples of both benchmarks and sophisticated problems confirm the accuracy and efficiency of the isogeometric analysis framework for thermally induced vibration analysis of space structures.展开更多
基金the Province Postdoctoral Foundation of Jiangsu(1501164B)the Technical Innovation Nurturing Foundation of Yangzhou University(2015CXJ016)China Postdoctoral Science Foundation(2016M600447)
文摘In a fusion reactor, the edge localized mode(ELM) coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power and improve its mitigating ability. The coil works in a high-temperature,high-nuclear-heat and high-magnetic-field environment. Due to the existence of outer superconducting coils, the coil is subjected to an alternating electromagnetic force induced by its own alternating current and the outer magnetic field. The design goal for the ELM coil is to maintain its structural integrity in the multi-physical field. Taking as an example the middle ELM coil(with flexible supports) of ITER(the International Thermonuclear Fusion Reactor), an electromagnetic–thermal–structural coupling analysis is carried out using ANSYS. The results show that the flexible supports help the three-layer casing meet the static and fatigue design requirements. The structural design of the middle ELM coil is reasonable and feasible. The work described in this paper provides the theoretical basis and method for ELM coil design.
基金co-supported by the Excellent Youth Science Foundation of China(No.51722501)the China Postdoctoral Science Foundation(No.2016M600027)+1 种基金the National Natural Science Foundation of China(Nos.51575025 and 61703022)the Preliminary Exploration of Project of China(No.7131474)
文摘With the high speed, the rotor of magnetically suspended permanent magnet synchronous motor(MSPMSM) suffers great thermal stress and mechanical stress resulting from the temperature rise problem caused by rotor losses, which leads to instability and inefficiency.In this paper, the mechanical–temperature field coupling analysis is conducted to analyze the relationship between the temperature field and structure, and multi-objective optimization of a rotor is performed to improve the design reliability and efficiency. Firstly, the temperature field is calculated by the 2 D finite element model of MSPMSM and the method of applying the 2 D temperature result to the 3 D finite element model of the motor rotor equivalently is proposed. Then the thermal–structure coupling analysis is processed through mathematic method and finite element method(FEM),in which the 3 D finite element model is established precisely in a way and approaches the practical operation state further. Moreover, the impact produced by the temperature and structure on the mechanical strength is analyzed in detail. Finally, the optimization mathematical model of the motor rotor is established with Sequential Quadratic Programming-NLPQL selected in the optimization scheme. Through optimization, the strength of the components in the motor rotor increases obviously and satisfies the design requirement, which to a great extend enhances the service life of the MSPMSM rotor.
基金financially supported by the National Natural Science Foundation of China(Grant No.U1906233)the Development Projects in Key Areas of Guangdong Province(Grant No.2020B1111040002)the Fundamental Research Funds for the Central Universities(Grant Nos.DUT20ZD213 and DUT20LAB308)。
文摘This work presents a numerical investigation of the thermal–fluid–structure coupling behavior of the liquid natural gas(LNG)transported in the flexible corrugated cryogenic hose.A three-dimensional model of the corrugated hose structure composed of multiple layers of different materials is established and coupled with turbulent LNG flow and heat transfer models in the commercial software ANSYS Workbench.The flow transport behavior,heat transfer across the hose layers,and structural response caused by the flow are analyzed.Parametric studies are performed to evaluate the impacts of inlet flow rate and thermal conductivity of insulation material on the temperature and structural stress of the corrugated hose.The study found that,compared with a regular operating condition,higher inlet flow velocities not only suppress the heat gain of the LNG but also lower the flow-induced structural stress.The insulation layer exhibits excellent performance in maintaining the temperature at the fluid–structure interface,showing little temperature change with respect to material thermal conductivity and ambient temperature.The simulation results may contribute to the research and design of the flexible corrugated cryogenic hoses and provide guidance for safer and more efficient field operations.
基金supported by International Thermonuclear Experimental Reactor (ITER) Specific Plan in China (2009GB101004)
文摘An ITER torus cryo-pump housing (TCPH), which encloses a torus cryo-pump, is connected to a vacuum vessel (VV) by a set of associated double bellows. There are complicated loads due to two different operating states (pumping and regeneration) and foreseeable accidents with the cryo-pump. This paper describes a thermal-structural coupled analysis of the present TCPH according to tho allowatfle stress criteria of RCC-MR, in which the worst cases and outcomes of various load combinations are obtained. Meanwhile, optimization of the structure has been carried oul, to obtain positive analysis results and an adequate safety margin.
文摘The coupling behavior of the imbedded weapon store occurring between the local unsteady flow field round the store and the structure response on the processing of opening its bay-door is simulated by using numerical method based on computational fluid mechanics(CFD).The transient aerodynamic behaviors when opening door under various flight altitudes and the corresponding structure deformation evolution in the unsteady flow fields are analyzed respectively and presented.The rules of aircraft attitude parameters′impacting to the responses of structure and the bay-door′s opening process are obtained by comparing with the analysis results.These rules can be applied to the structure design of bay-door and route specification of missile when disengaged and launched from within store.
基金supported partly by the National Natural Science Foundation of China (Nos.11302011, 11402013,11372023,11672018)the National Key Research and Development Program (No.2016YFB0200703)the Fundamental Research Funds for the Central Universities(No.YWF-14-HKXY-006)
文摘Several types of coupling methods for resolving aerothermoelastic problems associated with hypersonic wings are summarized,and the appropriate coupling methods for engineering calculations are selected.Then,the calculation and analysis methods for the subdisciplines in this field are introduced,and the time step issue is discussed.A two-way-coupling rapid static aerothermoelastic method for analyzing hypersonic wings is proposed.This method considers thermal effects and is used to conduct an aerothermoelastic response analysis for a hypersonic wing.In addition,the aerodynamic force,heat flux,structural deformation and temperature field are obtained.The following three conclusions are drawn.First,the heating effect has a significant impact on the static aeroelastic response of hypersonic wings;therefore,thermal protection shields are essential.Second,the application of thermal protection shields reduces the differences in the calculation results between the one-and two-way-coupling methods.Third,hypersonic wings exhibit large thermal deformation under high-temperature environments,and in certain cases,the thermal deformation is even larger than the deformation caused by aerodynamic force.
文摘A new calculating method of aerodynamic heating for unsteady hypersonic aircrafts with complex configuration is presented.This method,which considers the effects of high temperature chemical non-equilibrium and the heat transfer process in thermal protection structure,is based on the combination of the inviscid outerflow solution and the engineering method,where the Euler solver provides the flow parameters on boundary layer edge for engineering method in aerodynamic heating calculation.A high efficient interpolation technique,which can be applied to the fast computation of longtime aerodynamic heating for hypersonic aircraft,is developed for flying trajectory.In this paper,three hypersonic test cases are calculated,and the heat flux and temperature distribution of thermo-protection system are shown.The numerical results show the high efficiency of the developed method and the validation of thermal characteristics analysis on hypersonic aerodynamic heating.
文摘反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanical Engineers)规范中适用于核一级承压设备的相关标准和分析流程,对某型号反应堆的管道系统开展了结构强度校核及疲劳分析,数值结果表明:当前工况参数及出现次数叠加作用下管道系统的应力分类结果满足规范要求,不会出现不可逆的结构损伤,且关键结构不连续位置的疲劳累积使用因子均小于1,未出现累积使用因子超限问题。
基金Y.Guo would like to thank the National Natural Science Foundation of China(Grant No.11972187)and Priority Academic Program Development of Jiangsu Higher Education Institutions for their support.
文摘Spacecraft flexible appendages may experience thermally induced vibrations(TIV)under sudden heating loads,which in consequence will be unable to complete their intended missions.Isogeometric analysis(IGA)utilizes,in an isoparametric concept,the same high order and high continuity non-uniform rational B-splines(NURBS)to represent both the geometry and the physical field of the structure.Compared to the traditional Lagrange polynomial based finite element method where only C0-continuity across elements can be achieved,IGA is geometrically exact and naturally fulfills the C1-continuity requirement of Euler–Bernoulli(EB)beam elements,therefore,does not need extra rotational degrees-of-freedom.In this paper,we present a thermally induced vibration analysis framework based on the isogeometric method where thermal and structural behaviors are coupled.We fully exploited the higher order,higher continuous and geometric exactness of the NURBS basis with both benchmarks and sophisticated problems.In particular,we studied the thermally induced vibrations of the Hubble Space Telescope(HST)solar panel where main factors influencing thermal flutters are studied,and where possible improvements of the analytical reference methods are discussed.Additionally,thermally induced vibrations of the thin-walled lenticular tubes are studied and two new configurations of the tube are proposed to effectively suppress the thermally induced vibrations.Numerical examples of both benchmarks and sophisticated problems confirm the accuracy and efficiency of the isogeometric analysis framework for thermally induced vibration analysis of space structures.