为了研究船舶能量消耗的组成和EEOI的预测问题,以主机油耗作为研究重点,建立了船舶能效营运指数(ehip energy efficiency operational indicator,EEOI)分析预测仿真模型。建立了推进系统-船体运动-环境的联合数学模型,对船舶运动及推进...为了研究船舶能量消耗的组成和EEOI的预测问题,以主机油耗作为研究重点,建立了船舶能效营运指数(ehip energy efficiency operational indicator,EEOI)分析预测仿真模型。建立了推进系统-船体运动-环境的联合数学模型,对船舶运动及推进系统状态进行迭代计算。采用欧洲中期天气预报中心(European Centre for MediumRange Weather Forecasts,ECMWF)的气象数据,结合目标船的设计、实验参数及航线进行了仿真。根据对目标船在不同转速、不同航线的EEOI进行仿真,结果表明:不同主机转速对推进系统的能量消耗组成有显著影响。模型能够对不同转速的时间及EEOI进行预测,为航速设计提供依据;同时还能对不同航线的EEOI进行对比,为基于能效的航线优化提供了研究基础。展开更多
To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stabil...To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stability,this study introduces a‘Dynamic Event-Driven Co-Simulation’algorithm integrated with decision tree algorithms.This algorithm separates the overall coupling relationships and the main solver from the primary mod⁃el,utilizing a dynamic event monitoring module to adaptively adjust simulation strategies,including iteration pa⁃rameters,coupling relationships,and convergence criteria.This facilitates efficient adaptive simulations of dy⁃namic events while balancing solution accuracy and computational efficiency.The research focuses on a twinshaft turbofan engine,establishing six system-level models that encompass overall performance and various sub⁃systems based on three coupling methods,along with a multidisciplinary multi-fidelity simulation framework in⁃corporating a 3D CFD nozzle model.The study tests both model exchange and coupled simulation methods under a 14 s transient acceleration and deceleration scenario.In a 100%throttle condition,a high-fidelity nozzle model is used to analyze the sensitivity of different convergence criteria on computational efficiency and accuracy.Re⁃sults indicate that the accuracy and efficiency achieved with this method are comparable to those of PROOSIS soft⁃ware(18 s and 35 s,respectively),while being 71%more efficient than Simulink software(62 s and 120 s,re⁃spectively).Furthermore,appropriately relaxing the convergence criteria for the 0D model(from 10-6 to 10-4)while enhancing those for the 3D model(from 3000 steps to 6000 steps)can effectively balance computational accuracy and efficiency.展开更多
文摘为了研究船舶能量消耗的组成和EEOI的预测问题,以主机油耗作为研究重点,建立了船舶能效营运指数(ehip energy efficiency operational indicator,EEOI)分析预测仿真模型。建立了推进系统-船体运动-环境的联合数学模型,对船舶运动及推进系统状态进行迭代计算。采用欧洲中期天气预报中心(European Centre for MediumRange Weather Forecasts,ECMWF)的气象数据,结合目标船的设计、实验参数及航线进行了仿真。根据对目标船在不同转速、不同航线的EEOI进行仿真,结果表明:不同主机转速对推进系统的能量消耗组成有显著影响。模型能够对不同转速的时间及EEOI进行预测,为航速设计提供依据;同时还能对不同航线的EEOI进行对比,为基于能效的航线优化提供了研究基础。
文摘To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stability,this study introduces a‘Dynamic Event-Driven Co-Simulation’algorithm integrated with decision tree algorithms.This algorithm separates the overall coupling relationships and the main solver from the primary mod⁃el,utilizing a dynamic event monitoring module to adaptively adjust simulation strategies,including iteration pa⁃rameters,coupling relationships,and convergence criteria.This facilitates efficient adaptive simulations of dy⁃namic events while balancing solution accuracy and computational efficiency.The research focuses on a twinshaft turbofan engine,establishing six system-level models that encompass overall performance and various sub⁃systems based on three coupling methods,along with a multidisciplinary multi-fidelity simulation framework in⁃corporating a 3D CFD nozzle model.The study tests both model exchange and coupled simulation methods under a 14 s transient acceleration and deceleration scenario.In a 100%throttle condition,a high-fidelity nozzle model is used to analyze the sensitivity of different convergence criteria on computational efficiency and accuracy.Re⁃sults indicate that the accuracy and efficiency achieved with this method are comparable to those of PROOSIS soft⁃ware(18 s and 35 s,respectively),while being 71%more efficient than Simulink software(62 s and 120 s,re⁃spectively).Furthermore,appropriately relaxing the convergence criteria for the 0D model(from 10-6 to 10-4)while enhancing those for the 3D model(from 3000 steps to 6000 steps)can effectively balance computational accuracy and efficiency.
