To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the cons...To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the conservation laws with applicable multiphase fluid and choke models,these mathematical models are solved to characterize the hydraulics of an integrated system of reservoir,wells,chokes,flowlines,and separator at steady state.The controllable variables such as well count,choke size and separator pressure are adjusted to optimize the performance of the IPs at a specific time.It is found that increasing the well count can increase the bulk flow rate of the production network,but too many wells may increase the manifold pressure,leading to decline of single-well production.Increasing the choke size can improve the capacity of the IPs.The production of the IPs is negatively correlated with the separator pressure.With increasing separator pressure and decreasing choke size,the increment of total fluid production(the capacity of IPS)induced by increasing well count decreases.Validation tests with field examples show a maximum absolute deviation is 1.5%,demonstrating the robustness and validity of the proposed mathematical models and workflows.展开更多
Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper start...Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security展开更多
The fundamental task of well-facilitated farmland construction is to continuously lift the integrated production capacity. External project construction for well-facilitated farmland can not completely solve existing ...The fundamental task of well-facilitated farmland construction is to continuously lift the integrated production capacity. External project construction for well-facilitated farmland can not completely solve existing problems in improvement of intrinsic quality of farmland.Based on research findings of integrated production capacity of farmland,starting from basic elements such as water,soil,seed,fertilizer,and pesticide,this paper introduced factors influencing the integrated production capacity of well-facilitated farmland,including natural quality of farmland,supporting infrastructure,agricultural technology level and management level,and labor quality. Besides,it establish an evaluation system for integrated production capacity of well-facilitated farmland in Jiangsu Province by Analytic Hierarchy Process( AHP),and made an empirical study using indicator data of 2010- 2014. Results indicated that the general index of integrated production capacity of farmland in Jiangsu Province in 2010- 2014 was ascending,reflecting improvement of integrated production capacity of farmland. With the aid of radar map,it further found that the coupling between water,soil,seed,fertilizer,and pesticide and other elements play a crucial role in lifting the integrated production capacity of farmland. Finally,based on existing problems in construction of well-facilitated farmland in Jiangsu Province,it came up with some pertinent recommendations from the perspective of coordinated development of all elements.展开更多
Based on the governing equation of vibration of a kind of cylindrical shells written in a matrix differential equation of the first order, a new matrix method is presented for steady-state vibration analysis of a nonc...Based on the governing equation of vibration of a kind of cylindrical shells written in a matrix differential equation of the first order, a new matrix method is presented for steady-state vibration analysis of a noncircular cylindrical shell simply sup- ported at two ends and circumferentially stiffened by rings under harmonic pressure. Its difference from the existing works by Yamada and Irie is that the matrix differential equation is solved by using the extended homogeneous capacity precision integration＇ approach other than the Runge-Kutta-Gill integration method. The transfer matrix can easily be determined by a high precision integration scheme. In addition, besides the normal interacting forces, which were commonly adopted by researchers earlier, the tangential interacting forces between the cylindrical shell and the rings are considered at the same time by means of the Dirac-δ function. The effects of the exciting frequencies on displacements and stresses responses have been investigated. Numerical results show that the proposed method is more efficient than the aforementioned method.展开更多
To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where ...To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where the impact of battery energy storage system(BESS)flexibility is considered.First,we introduce distributionally robust chance constraints on network security and energy/carbon net-zero requirements,which form the upper and lower bounds of the feasible region.Then,the formulation and solution of the feasible region is proposed.The resulting analytical expression is a set of linear inequalities,illustrating that the feasible region is a polyhedron in a high-dimensional space.A procedure is designed to verify and adjust the feasible region,ensuring that it satisfies network loss constraints under alternating current(AC)power flow.Case studies on the 4-bus system,the IEEE 33-bus system,and the IEEE 123-bus system verify the effectiveness of the proposed method.It is demonstrated that the proposed method fully captures the spatio-temporal coupling relationship among PVs,loads,and BESSs,while also quantifying the impact of this relationship on the boundaries of the feasible region.展开更多
Aging network assets,forced and unforced outages,and the way the networks are operated in a deregulated market are of significant concerns to integrate large wind farms in a distribution network.In many cases,the cons...Aging network assets,forced and unforced outages,and the way the networks are operated in a deregulated market are of significant concerns to integrate large wind farms in a distribution network.In many cases,the constrained network capacity is a potential barrier to the large-scale integration of wind power.This paper probabilistically assesses the steady-state security in a distribution network in the presence of large wind farms.The approach incorporates active distribution network operating conditions,including intermittent power outputs,random outages,demand fluctuations,and dynamic interactions and exchanges,and then assesses the steady state security using Monte Carlo simulation.A case study is performed by integrating large wind farms into a distribution network.The results suggest that intermittent outputs of large wind farms in a distribution network can impact the steady-state security considerably.However,the level of impact of wind farms does not necessarily correlate with the installed capacity of them.展开更多
文摘To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the conservation laws with applicable multiphase fluid and choke models,these mathematical models are solved to characterize the hydraulics of an integrated system of reservoir,wells,chokes,flowlines,and separator at steady state.The controllable variables such as well count,choke size and separator pressure are adjusted to optimize the performance of the IPs at a specific time.It is found that increasing the well count can increase the bulk flow rate of the production network,but too many wells may increase the manifold pressure,leading to decline of single-well production.Increasing the choke size can improve the capacity of the IPs.The production of the IPs is negatively correlated with the separator pressure.With increasing separator pressure and decreasing choke size,the increment of total fluid production(the capacity of IPS)induced by increasing well count decreases.Validation tests with field examples show a maximum absolute deviation is 1.5%,demonstrating the robustness and validity of the proposed mathematical models and workflows.
基金Supported by the Achievement of Program for New Century Excellent Talents in Heilongjiang Province (1153-NCET-004)Project of Postdoctoral Scientific Research Launch Foundation in Heilongjiang Province
文摘Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security
基金Supported by Fundamental Research Funds for the Central Universities of China Pharmaceutical University(2015PYW01)
文摘The fundamental task of well-facilitated farmland construction is to continuously lift the integrated production capacity. External project construction for well-facilitated farmland can not completely solve existing problems in improvement of intrinsic quality of farmland.Based on research findings of integrated production capacity of farmland,starting from basic elements such as water,soil,seed,fertilizer,and pesticide,this paper introduced factors influencing the integrated production capacity of well-facilitated farmland,including natural quality of farmland,supporting infrastructure,agricultural technology level and management level,and labor quality. Besides,it establish an evaluation system for integrated production capacity of well-facilitated farmland in Jiangsu Province by Analytic Hierarchy Process( AHP),and made an empirical study using indicator data of 2010- 2014. Results indicated that the general index of integrated production capacity of farmland in Jiangsu Province in 2010- 2014 was ascending,reflecting improvement of integrated production capacity of farmland. With the aid of radar map,it further found that the coupling between water,soil,seed,fertilizer,and pesticide and other elements play a crucial role in lifting the integrated production capacity of farmland. Finally,based on existing problems in construction of well-facilitated farmland in Jiangsu Province,it came up with some pertinent recommendations from the perspective of coordinated development of all elements.
基金Project supported by the Doctoral Foundation of the National Education Ministry of China(No.20040487013)
文摘Based on the governing equation of vibration of a kind of cylindrical shells written in a matrix differential equation of the first order, a new matrix method is presented for steady-state vibration analysis of a noncircular cylindrical shell simply sup- ported at two ends and circumferentially stiffened by rings under harmonic pressure. Its difference from the existing works by Yamada and Irie is that the matrix differential equation is solved by using the extended homogeneous capacity precision integration＇ approach other than the Runge-Kutta-Gill integration method. The transfer matrix can easily be determined by a high precision integration scheme. In addition, besides the normal interacting forces, which were commonly adopted by researchers earlier, the tangential interacting forces between the cylindrical shell and the rings are considered at the same time by means of the Dirac-δ function. The effects of the exciting frequencies on displacements and stresses responses have been investigated. Numerical results show that the proposed method is more efficient than the aforementioned method.
基金supported by the Natural Science Foundation of Tianjin(No.22JCZDJC00820)。
文摘To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where the impact of battery energy storage system(BESS)flexibility is considered.First,we introduce distributionally robust chance constraints on network security and energy/carbon net-zero requirements,which form the upper and lower bounds of the feasible region.Then,the formulation and solution of the feasible region is proposed.The resulting analytical expression is a set of linear inequalities,illustrating that the feasible region is a polyhedron in a high-dimensional space.A procedure is designed to verify and adjust the feasible region,ensuring that it satisfies network loss constraints under alternating current(AC)power flow.Case studies on the 4-bus system,the IEEE 33-bus system,and the IEEE 123-bus system verify the effectiveness of the proposed method.It is demonstrated that the proposed method fully captures the spatio-temporal coupling relationship among PVs,loads,and BESSs,while also quantifying the impact of this relationship on the boundaries of the feasible region.
文摘Aging network assets,forced and unforced outages,and the way the networks are operated in a deregulated market are of significant concerns to integrate large wind farms in a distribution network.In many cases,the constrained network capacity is a potential barrier to the large-scale integration of wind power.This paper probabilistically assesses the steady-state security in a distribution network in the presence of large wind farms.The approach incorporates active distribution network operating conditions,including intermittent power outputs,random outages,demand fluctuations,and dynamic interactions and exchanges,and then assesses the steady state security using Monte Carlo simulation.A case study is performed by integrating large wind farms into a distribution network.The results suggest that intermittent outputs of large wind farms in a distribution network can impact the steady-state security considerably.However,the level of impact of wind farms does not necessarily correlate with the installed capacity of them.
