Aircraft icing can significantly degrade aerodynamic performance and compromise flight safety,highlighting the need for efficient prediction of icing characteristics and critical influencing factors.In this study,a st...Aircraft icing can significantly degrade aerodynamic performance and compromise flight safety,highlighting the need for efficient prediction of icing characteristics and critical influencing factors.In this study,a structured set of icing simulation parameters was defined by identifying key variables and constraining their ranges in accordance with airworthiness requirements of intermittent maximum icing conditions.According to the simulation results,it concludes that heavier ice accretion leads to increased surface roughness and consequently more severe aerodynamic degradation under the intermittent maximum icing conditions.Within this admissible domain,representative samples were generated and applied to FENSAP-ICE to simulate ice accretion on the reference aircraft airfoil,thereby constructing a comprehensive icing dataset with the iced mass as the output response.Based on this dataset,a surrogate model employing the Random Forest algorithm was developed,enabling rapid and reliable prediction of icing outcomes.Furthermore,sensitivity analysis was conducted to identify the dominant parameters governing the icing process,offering valuable insights into the core factors that critically influence aircraft icing behavior.展开更多
A comprehensive simulation model is established to design the altitude adjustment of the stratospheric airship with the application of the adjustable ballonets for pitch control.A series of mathematical models,includi...A comprehensive simulation model is established to design the altitude adjustment of the stratospheric airship with the application of the adjustable ballonets for pitch control.A series of mathematical models,including atmosphere,thermal,dynamics and kinematics,airship pressure and pitch control,are developed to achieve the altitude adjustment when the stratospheric airship flying at the stationary phase.The altitude adjustment strategy takes the thermodynamics,dynamics,and pressure control requirements together into consideration,to better fulfill the realistic flight conditions.Based on these models,the characteristics of stratospheric airship’s flight performance are simulated and discussed in detail.The results show that taking adjustable ballonets as the actuator can realize the pitch and pressure control simultaneously and satisfy the requirements of the flight missions.Furthermore,stratospheric airship can achieve altitude adjustment with the application of adjustable ballonets and propulsion system coordinately.Moreover,the simulationmodel can accurately present the interaction of thermodynamics,pressure,and dynamics,which better satisfies the realistic flight situation.The results and conclusions presented herein contribute to the design and operation of stratospheric airship.展开更多
文摘Aircraft icing can significantly degrade aerodynamic performance and compromise flight safety,highlighting the need for efficient prediction of icing characteristics and critical influencing factors.In this study,a structured set of icing simulation parameters was defined by identifying key variables and constraining their ranges in accordance with airworthiness requirements of intermittent maximum icing conditions.According to the simulation results,it concludes that heavier ice accretion leads to increased surface roughness and consequently more severe aerodynamic degradation under the intermittent maximum icing conditions.Within this admissible domain,representative samples were generated and applied to FENSAP-ICE to simulate ice accretion on the reference aircraft airfoil,thereby constructing a comprehensive icing dataset with the iced mass as the output response.Based on this dataset,a surrogate model employing the Random Forest algorithm was developed,enabling rapid and reliable prediction of icing outcomes.Furthermore,sensitivity analysis was conducted to identify the dominant parameters governing the icing process,offering valuable insights into the core factors that critically influence aircraft icing behavior.
基金supported by the National Nature Science Foundation of China under Grant No.51906141.
文摘A comprehensive simulation model is established to design the altitude adjustment of the stratospheric airship with the application of the adjustable ballonets for pitch control.A series of mathematical models,including atmosphere,thermal,dynamics and kinematics,airship pressure and pitch control,are developed to achieve the altitude adjustment when the stratospheric airship flying at the stationary phase.The altitude adjustment strategy takes the thermodynamics,dynamics,and pressure control requirements together into consideration,to better fulfill the realistic flight conditions.Based on these models,the characteristics of stratospheric airship’s flight performance are simulated and discussed in detail.The results show that taking adjustable ballonets as the actuator can realize the pitch and pressure control simultaneously and satisfy the requirements of the flight missions.Furthermore,stratospheric airship can achieve altitude adjustment with the application of adjustable ballonets and propulsion system coordinately.Moreover,the simulationmodel can accurately present the interaction of thermodynamics,pressure,and dynamics,which better satisfies the realistic flight situation.The results and conclusions presented herein contribute to the design and operation of stratospheric airship.
